NATIVE PLANT SOCIETY OF TEXAS
Convergence and Diversity:
Native Plants of South Central Texas
2006 Symposium Proceedings
October 19-21, 2006
San Antonio, Texas
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TABLE OF CONTENTS
Presentations:
Geologic History As It Relates to Modern Vegetation Patterns of South Central Texas. . . . . . . 1
Bill Ward
An Overview of the Flora of South Central Texas. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Jason Singhurst
Revelations from the Past: Consequences for the Future. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Mark Peterson
Hummingbirds and Native Plants: Has Codependence Resulted in Simultaneous Adaptation?. 18
Mark Klym
Soil MesoFauna: Meet Some of the Plant Root Neighborhood (A Movie of Unexpected
Organisms). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
Patricia Richardson
Solving Problems with Native Plants. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Mark Simmons
Diversity, Invasive Species and Designing Invasion Resistant Communities. . . . . . . . . . . . . . . .27
Kelly Lyons
Butterflies and Native Plants of South Central Texas. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38
Bill Lindemann
¿Quién Es Mas Macho?. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48
Paul Cox
Running Dry: Water and Development in San Antonio. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Char Miller
Protecting Our Water and Natural Heritage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
Eric Lautzenheiser
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Workshop Papers:
Sabal Mexicana Palm Trees, Native to San Antonio. And Beyond?. . . . . . . . . . . . . . . . . . . . . .79
Landon Lockett
Contributed Papers:
What’s Latin, What’s Local: Taxonomy of the Flora of the Southwest . . . . . . . . . . . . . . . . . . . .90
Patricia Rektorik-Sprinkle
Field Trips. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
Workshops. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .97
About the Presenters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
Symposium Program Committee
Eric Lautzenheiser, Patty Leslie-Pasztor, Janis Merritt,
Melissa Miller, Lottie Millsaps, Bill Ward
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Geologic History as it Relates to Modern Vegetation Patterns of South Central Texas
Bill Ward
Emeritus Professor of Geology, University of New Orleans
Founding President, Boerne Chapter, NPSOT
Introduction
Major patterns of vegetation in South Central Texas closely match the major patterns of
the surface geology (Fig. 1). The variety of rock types at or near the surface in South Central
Texas ensures that the region has a diversity of soils and landforms, which together with the
climate, strongly influence the composition of the flora of this area.
The juxtaposition of diverse rock types and landforms in South Central Texas can be
explained through a brief geologic history of this area. For this purpose, there is no need to
consider more than the latest seven percent of the Earth’s 4.5-billion-year history. The
abbreviated geologic history recounted below begins about 300 million years ago during the
Pennsylvanian Period and comes forward, in uneven hops, to modern times. This story is based
on interpretations of rocks at the surface or in the subsurface of South Central Texas.
Abbreviated Geologic History
Pennsylvanian Period
We begin with the Pennsylvanian Period (Fig. 2), because during that time an event
occurred that established the fundamental structural framework of this part of the North
American continent and strongly influenced the subsequent geologic history. The effects of this
event are seen in the modern geology and, consequently, the modern vegetation.
The area that is now South Central Texas was mountainous during late Pennsylvanian
time (Fig. 3). This was because late in the Paleozoic Era (Fig. 2), the continental masses of the
world were drawn together by convective currents flowing within the almost-molten upper
mantle, the layer of the Earth upon which the large segments (plates) of continental and oceanic
crust float.
When the North American continent was brought into collision with the South American
continent during the Pennsylvanian Period, the thick layers of marine sedimentary rock that had
accumulated on the continental margins were crumpled into a belt of folded, faulted, and partly
metamorphosed strata. This zone of deformed rock rose up to form the Ouachita Mountains, a
westward extension of the southern Appalachian Mountain Belt. During the continental
collision, the Ouachita belt was bent around the stable Llano-area promontory of Precambrian
igneous and metamorphic rocks, causing the Ouachita Mountains to trend northeast between San
Antonio and Dallas and east-west between San Antonio and Del Rio.
Permian-Triassic-Middle Jurassic Periods
For the next 100 million years or so, the future South Central Texas area was part of a
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Figure 1A. – Vegetative regions of South Central Texas and adjacent areas (from Hatch et al.,
1990). 2 = Gulf Prairies and Marshes; 3 = Post Oak Savannah; 4 = Blackland Prairies; 5 = Cross
Timbers and Prairies; 6 = South Texas Plains; 7 = Edwards Plateau
Figure 1B. – Geologic map of South Central Texas and adjacent areas (Bureau of Economic
Geology, University of Texas, 1992).
Qu = Quaternary undivided
Qb = Quaternary, Beaumont Formation
Ql = Quaternary, Lizzie Formation
Pow = Pliocene, Willis Formation
Mog = Miocene, Goliad Formation
Mof = Miocene, Fleming and Oakville Formations
Oc = Oligocene, Catahoula Formation
Ej = Eocene, Jackson Group
Ec2 = Eocene, Claiborne Group (Yegua Formation)
Ec1 = Eocene, Claiborne Group (Cook Mt., Sparta, Weches, Queen City, Reklaw Formations)
EPA = Eocene-Paleocene, Wilcox and Midway Groups
Ku2 = Upper Cretaceous, Navarro and Taylor Groups
Ku1 = Upper Cretaceous; Austin, Eagle Ford, upper Washita Groups
Kl2 = Lower Cretaceous, Fredricksburg and lower Washita Groups
Kl1 = Lower Cretaceous, Trinity Group
lPam = lower Pennsylvanian, Atokan and Morrowan Series
Pau = Paleozoic undivided
C = Cambrain
pC = Precambrian
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Figure 2. – Geologic time scale showing eras and periods of the Phanerozoic Eon and
epochs of the Cenozoic Era. Ages noted at the time boundaries are in millions of years
before present.
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continental terrain (Fig 4). Stream systems crossed this area, depositing gravel, sand, and mud.
Gradually, the Ouachita Mountains were worn down by weathering and erosion.
During the Triassic, rifts in the continental crust began to create elongate basins (Fig. 4) which
eventually would continue to split and spread apart to create narrow ocean basins, the first stages
of the Atlantic Ocean and Gulf of Mexico (Fig. 5). During this time, the continental crust along
the southeastern flank of the Ouachita belt began to subside relative to the land mass on the
northwestern side of this belt of deformed rocks. This subsided area would become the
northwestern rim of the Gulf basin. The configuration of the early Gulf rim, therefore, was
controlled by the location of the old Ouachita Mountain Belt.
Late Jurassic Period
During Late Jurassic around 150 million years ago, the area now South Central Texas lay
on the margin of the ancestral Gulf of Mexico (Fig. 6). Circulation of ocean currents into the
Atlantic and Gulf of Mexico ocean basins was inhibited by constricted openings, and the climate
was hot with high rates of evaporation. Consequently, the water in these narrow seas was
extremely saline and dense. Salt precipitated along the margins of the ocean basins, in some
places accumulating to many hundreds, even thousands of feet thick. Landward, the salt deposits
thinned out against the rim of the ancestral Gulf. Although this salt layer subsequently was
deeply buried under younger sedimentary rocks, it played a major role in later geologic history of
South Central Texas.
As the Gulf and Atlantic continued to spread wider, oceanic circulation improved and
more-normal salinity prevailed in the seaways. With the normal salinity, the typical sediment
deposited along the western flank of the Gulf was carbonate sediment (debris of calcium
carbonate shells and skeletons of marine organisms living on the sea floor; the source of
limestone and dolostone). Sand and mud were eroded off the continent and deposited in the
coastal-plain and near-shore zones.
Cretaceous Period
Early in the Cretaceous, the shoreline of the northwestern Gulf was in the South Central
Texas area (Fig. 7). The adjacent land area was generally low-lying except for the Llano
complex of very old Precambrian and Paleozoic rocks, which stood high and exposed to erosion.
The Llano Uplift shed sand and mud into the coastal-plain stream systems and onto the shallow
sea floor (future Sycamore and Hensel Sandstones), interfingering with layers of carbonate
sediment farther out on the shallow-marine shelf (future Cow Creek and Glen Rose
Limestones).
During the Cretaceous Period, the Gulf of Mexico widened almost to its present
configuration. The continental margin in the Texas area subsided and the sea gradually
encroached farther and farther inland. About 100 million years ago, before the end of the Early
Cretaceous, even the Llano-area island was inundated and covered by thick layers of marine
calcareous sediment (future Edwards limestone).
As the area slowly subsided and sea level rose, the Late Cretaceous sea covered most of
Texas and extended far to the northwest as part of an inland seaway connecting to the North
Pacific Ocean (Fig. 8). In time, many hundreds of feet of Upper Cretaceous marine limestone,
chalk, and mudstone accumulated in the South Central Texas area.
Around 85 million years ago, at the time the Austin Chalk was being deposited across
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South Central Texas, several volcanoes erupted on the sea floor along the northwestern rim of
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the Gulf basin. Some larger piles of lava rock built up high enough to be volcanic islands.
These volcanic rocks are dark and heavy, rich in iron and magnesium, indicating they were
crystallized from magma generated at great depths. Apparently, pulses of widening of the Gulf
basin caused rifts deep into the crust or upper mantle that allowed magma to make its way to the
sea floor.
Hundreds of miles west and northwest of South Central Texas during Late Cretaceous,
the Rocky Mountains began to develop. As the mountains rose up and were eroded, streams
brought great amounts of sediments onto the marine shelf of Texas where carbonate sediment
was accumulating. Uppermost Cretaceous rocks (Navarro Group) in South Central Texas are
mostly thick layers of marl and calcareous clay, the product of mixing the carbonate sediment
with the influx of mud from the rising land area. As the Cretaceous Period drew to a close 65
million years ago, the extensive continental sea retreated toward the Gulf Basin.
Paleogene (Early Tertiary Period)
At the beginning of the Tertiary Period (Fig. 2), South Central Texas was a muddy sea
floor receiving copious amounts of sediment as the continent interior rose higher. During the
Eocene, South Central Texas was on the northwestern margin of the Gulf of Mexico, fluctuating
in time from coastal-plain to shallow-marine environments (Fig. 9). At times large delta plains
with channels, coastal marshes, and bays (e.g., part of the Wilcox Group and Yegua Formation)
built out onto the shallow-marine shelf. At other times sheets of coastal-plain and shoreline sand
(e.g., Carrizo Sand and Queen City Sand) spread across the area.. From time to time, the
shoreline advanced farther landward and South Central Texas was a shallow sea floor covered
with marine mud and sand (e.g., Reklaw and Weches Formations).
During late Eocene, sediment eroded off the mainland continued to be dumped into the
Gulf, gradually building the land area farther and farther gulfward. From late Eocene on, South
Central Texas was a continental terrain.
From late Eocene to earliest Miocene, stream systems and westerly winds brought ash
and coarser debris from the volcanoes erupting in far West Texas, the western US, and northern
Mexico to South Central Texas. This is when the Whitsett and Catahoula Formations, both rich
in ash and volcanic-rock fragments, were deposited on the Texas coastal plain.
Neogene
By the beginning of the Miocene Epoch (Fig. 10), the northwestern rim of the Gulf basin
had received great volumes of sediment, stacked layer upon layer since the Jurassic Period . All
the while as the sediments accumulated, the basin margin slowly subsided.to accommodate the
many thousands of feet of marine sedimentary rock that now lay under the Texas coastal plain.
Near the bottom of this thick stack of rocks was the layer of Jurassic salt, and under great
overburden pressure, rock salt flows like warm wax. This is not a stable substrate for overlying
rocks.
About 25 million years ago or so, probably in response to a pulse of Gulf widening, the
Mesozoic and Cenozoic sedimentary layers crept toward the center of the Gulf by sliding across
the top of the Jurassic salt. The slipping rock layers were stretched away from equivalent layers
that had been deposited farther landward on more stable substrates beyond the perimeter of the
salt layer. The slipping and crustal pull-apart resulted in zones of faults parallel to the rim of the
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Gulf basin (i.e., parallel to the trend of the Pennsylvanian Ouachita mountain belt). This is the
origin of the Balcones fault system and a similar fault zone near Luling (Fig. 11 ). The Balcones
faults are essentially a series of downsteps that progressively lower the faulted strata toward the
Gulf.
Figure 11. – Schematic delineation of Balcones and Luling Fault zones (from Collins and
Hovorka, 1997).
South and east of the fault zone, the Gulf basin continued to slowly subside,
progressively warping the Mesozoic and Cenozoic rock layers downward toward the Gulf basin.
North and west of the Balcones fault zone the area remained a relatively stable and high
platform. Gulfward-flowing streams began to rapidly erode the high plateau, stripping away the
layers of Cenozoic and Cretaceous rock and spreading the eroded debris out onto the coastal
plain. Miocene and Pliocene stream-system deposits (e.g., Oakville and Goliad Formations)
contain chert and Cretaceous fossil fragments eroded from the highland.
Quaternary
Several times during the late Pliocene and Pleistocene (the last few million years),
glaciers built up over the North Pole, locking up water and thereby lowering sea level. For
example, the Gulf of Mexico was nearly 300 feet lower than present during the height of the
most recent glacial period about 18,000 years ago. When sea level was low, stream gradients
were increased and the landscape was rapidly eroded.
The stream-dissected plateau north and west of the Balcones fault was eroded down to
the Lower Cretaceous limestones, which weathered into a karst terrain, now called the Edwards
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Plateau. Large springs issuing from Edwards Plateau limestones became head waters for the
major rivers that flow across South Central Texas today.
As the Gulf basin continued to subside, the rock layers underlying the coastal plain were
tilted toward the Gulf so that their landward ends were turned up and eroded off. For example,
on the upper coastal plain just southeast of San Antonio, Eocene sandstone and mudstone crop
out. Where the sandstone formations (e.g., Carrizo Sand) come to the surface are prominent
cuestas with their steep sides facing northwest. Where the softer muddy Eocene rocks crop out
are elongate erosional valleys. Between the Balcones fault zone and the Gulf, the outcropping
strata are progressively younger toward the sea (Fig. 12A).
Consequences of Geologic Evolution of South Central Texas
The geologic evolution of South Central Texas has resulted in a varied landscape
underlain by diverse rock types (Fig.12A ). On the southeastern Edwards Plateau, karst
topography is developed on Lower Cretaceous carbonate rock (limestone and dolostone) (Fig.
12A). Thin dark-colored basic top soils characterize this area (Fig.12 B).
Paralleling the eastern and southern margins of the Edwards Plateau is a narrow belt of
Upper Cretaceous chalk and marl preserved in down-dropped blocks of the Balcones fault zone.
This area has thick dark-colored clayey soils that shrink and swell upon drying and wetting (Fig.
12 B) and is the southwestern end of the Blackland Prairies (Fig.1A).
Southeastward of the strip of Upper Cretaceous rock, is a broad area of Paleogene
sandstones and mudstones (Fig. 12 A). East of San Antonio these rocks crop out on the Post Oak
Savannah (Fig. 1A), and south of San Antonio similar rocks underlie the upper South Texas
Plains vegetation region. Soil zones in these areas have leached topsoil and accumulations of
clay in the B horizon (Fig. 12 B).
Farther toward the Gulf is a belt of Miocene calcareous sandstone and mudstone
(Fig.12A), partly derived from erosion of Cretaceous limestone from the Edwards Plateau. East
of San Antonio this outcrop corresponds to a distal belt of Blackland Prairies (Figs.1A and 12B).
South of San Antonio the Miocene outcrop belt has soil similar to that of the Edwards Plateau
(Fig. 12B).
Even though the Paleogene and lower Neogene sandstone and mudstone units continue to
the southwest, they are all included in the South Texas Plains vegetation region (Fig. 1A). This
may indicate that climate is a greater influence on vegetation zones in this area than are rock and
soil types. The South Central Texas climate is characterized by a southward increase in mean
annual temperature and a westward and southwestward decrease in mean annual total
precipitation.
In summary, the convergence of the four major vegetation zones in South Central Texas
is intimately related to the geologic history of the region. Although not considered in this paper,
the geologic history also directly influenced two other important factors that determined the
present-day vegetation patterns: plant evolution and climate history.
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Figure 12A. – Rock types cropping out in South Central Texas and adjacent areas.
Figure 12B. – Major soil orders in South Central Texas and adjacent areas (after TA&MU Soil
Characterization Lab, 2006).
Mollisol = grassland soil with high base status
Vertisol = clayey soil with high shrink/swell capacity
Alfisol = moderately leached soil with subsurface zone of clay accumulation and >35% base
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Selected References
Blakey, R., 2006, Sedimentation, tectonics, and paleogeography of North Atlantic region:
http://jan.ucc.edu/reb7/nat.html.
Collins, E.W., and Hovorka, S.D., 1997, Structure map of the San Antonio segment of the
Edwards Aquifer and Balcones fault zone, south-central Texas: Structural framework of a
major limestone aquifer: Kinney, Uvalde, Medina, Bexar, Comal, and Hays Counties:
The University of Texas at Austin, Bureau of Economic Geology, Miscellaneous Map
No. 38, scale 1:250,000, 2 sheets.
Gradstein, F.M., Ogg, J.G., Smith, A.G., et al., 2004, A Geologic Time Scale: Cambridge
University Press.
Hatch, S.L., Gandhi, K.N., and Brown, L.E., 1990, Checklist of the vascular plants of
Texas: Texas Agricultural Experiment Station Miscellaneous Publication 1655, 158 p.
Soil Characterization Lab, Texas A&M University, 2006, Dominant Soil Orders of Texas (map):
http//soildata.tamu.edu/ordermap.htm
Spearing, D., 1991, Roadside Geology of Texas: Mountain Press Publishing Company, 418 p.
Copyright © 2006 by Bill Ward
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An Overview of the Flora of South Central Texas
Jason Singhurst
Botanist/Plant Community Ecologist
Science, Research and Diversity Program
Texas Parks and Wildlife Department
3000 S IH-35, Ste. 100
Austin TX 78704
(512) 912-7026
[email protected]
NOTES
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Revelations from the Past, Consequences for the Future
Mark Peterson
Urban Forester, Alamo Region
Texas Forest Service
NOTES
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Hummingbirds and Native Plants:
Has Codependence Resulted In Simultaneous Adaptation?
Mark Klym
Coordinator, Texas Hummingbird Roundup
Texas Parks and Wildlife Department
4200 Smith School Road
Austin, TX 78744
512-389-4644
[email protected]
The relationship between hummingbirds and native plants has long been known, and many of the
famous hummingbird “hot spots” are known not only for the hummingbirds they attract, but also
for the brilliant wildflower displays that create the attraction. This relationship though, has also
resulted over the millennia in adaptations by both plants and birds to make the codependence
more efficient for their purposes. This paper will examine some of these adaptations, not only in
the wildflowers, but also in other plants, with the goal of encouraging the use of native plants in
our landscapes to attract these birds and of stirring some conscientious and deliberate
observation and selection in our plant choices.
Hummingbirds. The mere thought of them brings a smile to the face and a sparkle to the
eye of most Americans. They are a uniquely American phenomenon, being unknown in the old
world, but universally possible in the new world. Yet many of our gardening habits – the
selection of flowering plants, the removal of cover and even our plant grooming habits – have
failed to take into account the remarkable physical and behavioral adaptations of these birds that
have developed over millennia with our native plants.
In North America, we are familiar with hummingbirds that have long, slender bills, often
with a slight downward curve. These birds however, are generally accepted as relatively recently
evolved. A field guide of Mexican birds will list 10 or more species of hummingbird before our
first Texas species is presented (Edwards, 1998) and these are perhaps the more primitive species
within the family (Williamson, 2001).
Hermits, among the most primitive of hummingbird
species, often have a long, sharply down curved bill. Coquettes and emeralds, which also appear
early in the taxon, are relatively short, very straight, sharp billed species. The differences are
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reflected in feeding habits of the birds, and often in the selection of plants they will choose to
feed from. Coquettes, emeralds and other primitive birds are often known to cut the corolla of
the plans with their bill and “steal” nectar from the blossom, thus by-passing the reproductive
mechanism of the plant at a resulting detriment to the plant. Many plants in regions where these
birds are common have developed a hardened corolla in attempts to frustrate this practice.
The length of the bird’s bill and the extremely long tongue of hummingbirds appear also
to be an adaptation to a mechanism developed by plants to frustrate nectar “stealing” insects.
The long, colorful corolla of many favored hummingbird plants makes it difficult, if not
impossible, for bees, beetles, and other insects to access the nectar. The long slender bill and
extremely extensile tongue – in many species extending longer than the bill itself – make it
possible for the bird to access this nectar while still ensuring that the plant is likely to be
pollinated in the process.
Many plants have taken advantage of the hovering and aerobatic capabilities of these
birds in the design and placement of their flowers. By orienting their flowers to approach 90
degrees from the stem, these plants reduce the probability of butterflies and other organisms that
fly only short distances before seeking another food source will be successful in fertilizing the
flower. Butterflies would have to orient themselves nearly on their back to successfully extend
their tongue into the flower and access the nectar. Birds on the other hand, simply hover below
the corolla and thrust bill and tongue into the flower to feed. Protruding, or overly long anthers
ensure the pollen is likely to be deposited on the head, throat, bill and body of the bird, making it
likely that the next plant it visits will receive a gift of pollen on the ovaries.
Behavior can also be influenced by the food resources. Hummingbirds are among the
few bird species that do not form a pair bond – not even for the short nesting season. Once
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mating is done, the pair separate and the female takes all responsibility for raising the next
generation. Might this be an adaptation to the plant habit of producing small amounts of nectar
with routine, almost clocklike periodicity? Might that same small, periodical production of the
food resource not also account for the highly aggressive protection of those same food resources?
Does the timing of nectar production and bloom period possibly influence migration, nesting,
and other habits of the birds?
Exotic plants can also provide these resources, but the birds are familiar with, and often
look for the native plants they have fed on in the past.
We often look only at the food resources for a relationship between plants and birds, but
what about other habitat requirements met by native plants? Native plants provide the shelter
needed by these birds for nesting, resting, and escape. While exotic plants can again meet these
needs, native plants provide them without the threat of invasive or other undesirable impacts.
Hummingbirds often nest in trees or bushes, their nest height ranging from a couple of
feet to more than 40 feet above ground. Trees that have thick canopies and opposite or near
opposite branching are more likely to host a nest. Bushes with similar branching structures,
especially heavily armed, species, are likewise probable hummingbird nest sites. What does the
plant gain from having a nest in it? Hummingbirds are ravenous eating machines that require
protein – which they gain by gleaning insects from branches, leaves and flowers and by hawking
insects around the plant! Structures and flowers that are attractive to the insects make it more
likely the bird will nest nearby!
So what can the native plant enthusiast do to make it more likely that they will see and
enjoy one of these accomplished aerial acrobats in their garden in Texas? Select native plants
that are nectar producers – not all plants produce nectar. Select native plants that will produce
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their nectar over an extended period with an emphasis on those plants that will provide for the
birds in critical season. Select native plants that favor birds over butterflies, bees or beetles,
although some insect favoring plants will be essential to the healthy hummingbird habitat.
Encourage your communities, civic interest groups and businesses to consider the birds and their
needs in their selection of landscape materials and regulations.
These two groups of organisms have developed with a mutual codependency. We, as
native plant enthusiasts, need to consider the birds since, without the birds we soon lose the
plants.
Literature Cited
Edwards, Ernest P. 1998. A field guide to the birds of Mexico and adjacent areas. Belize,
Guatemala and El Salvador. Austin, Texas: University of Texas Press.
Williamson, Sheri L. 2001. Peterson field guides hummingbirds of North America. New York:
Houghton Mifflin.
Copyright © 2006 by Mark Klym.
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Soil MesoFauna – Meet Some of the Plant Root Neighborhood
(A Movie of Unexpected Organisms)
Patricia Q. Richardson
Research Fellow, Integrative Biology
University of Texas
1 University Station A6700
Austin TX 78712
(512) 471-4128
[email protected]
Soil mesofauna are an essential community of life in healthy soil. They are crucial to cycling
nutrients in soil and plants. They are crucial to dispersing bacteria and fungi in soil. They are part
of the web of life that surrounds us. We are part of the web of life that surrounds them. What can
we learn by observing them?
I, the human being writing this, am composed of approximately 100 trillion cells, of
which only 10 trillion come from my parents. What are the other 90 trillion cells? Can I call
myself a human being if only one out of ten cells of the organism I call myself is human? If I am
one tenth human, what are my other nine tenths? It turns out that they are mostly bacteria with a
few protozoa and fungi thrown in. You likely have been aware when you have disrupted your
“other nine tenths”. You got diarrhea or you heaved your guts out. So am I just infrastructure for
my bacterial entity?
Looking at the leaves of a tree in your yard, how many cells of the leaf are plant cells?
The world of leaves is simultaneously the world of fungi and bacteria living intimately with each
other, not only on surfaces but also inside leaves. Fungi quietly living inside the plant, so is it a
fungi cloaked in plant, or a plant woven in fungi?
A teaspoon of healthy soil has parent material (sand, silt, clay) that is glued and woven
together by bacteria and fungi, grazed upon by mites and springtails, masticated by earthworms,
and pooped in by everyone. Maybe trees are really just beautiful perturbations of the soil – a
plant infrastructure to enable soil bacteria and fungi to arrange an above ground vegetation
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home. Maybe if our human eyes could see the teeming masses of bacteria in everything and on
everything, entering everything and exiting everything, we would be much more aware of the
complexity of interaction in the web of life.
Plant roots actively attract bacteria and fungi by exuding carbohydrates and proteins. No
one entirely understands why plants expend their hard-earned energy to feed the soil organisms
around their roots, but they do. It is recognized that mycorrhizal fungi bring nutrients and
moisture to their host plant. Do concentrations of bacteria act as a defensive hoard around the
root? We could ask a hundred questions and arrive at few answers. Fortunately plants know the
whole story. Our main responsibility is to not destroy the community that each plant nurtures.
My research has led to videography of some of the mid-sized organisms found in healthy
soil. They are much bigger than bacteria (bacteria represent the microfauna) and much smaller
than earthworms (earthworms represent the megafauna). They are the middle-sized, the
mesofauna. They range in size from .25 to several millimeters in length. They include mites,
collembola, diplura, paropoda, symphyla, pseudoscorpions, isopoda, and protura. They would
look like specks in your hand. They occur in all soils on earth. What do soil mesofauna do, and
why should we care?
Soil mesofauna live in the air-filled pore spaces in the soil. They are usually not powerful
enough to dig their own way underground. Megafauna such as dung beetles and earthworms can
dig their own tunnels and burrows. Very low numbers of mesofauna in a soil may indicate that
the soil has poor tilth and is not well aerated.
Soil mesofauna include herbivores, fungivores, insectivores, carnivores, bacteriavores,
poopavores, omnivores.… You name it, something eats it. The result is excellent availability of
nutrients for a diversity of life forms including plants. If you’re a mite who slurps bacteria, some
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of those bacteria will be in dormant spore form. You wander off and eventually poop. The spores
come through intact, and you have just introduced that bacteria into new territory. Your mite
poop – nicely digested bacteria - releases nutrients in forms that plants in the neighborhood can
use.
The complexity of the web of life is far beyond our imagination. Our contribution is to
feed the soil, and leave the myriad soil organisms to sort the complexity out.
A good overall reference for learning about life in soil is the Soil Biology Primer. It is
available online at: http://soils.usda.gov/sqi/concepts/soil_biology/index.html.
Copyright © 2006 by Patricia Q. Richardson.
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Solving Problems with Native Plants
Mark Simmons
Ecologist, Landscape Restoration Program
Lady Bird Johnson Wildflower Center
University of Texas at Austin.
4801 Lacrosse Avenue
Austin, Texas. 78739
(512) 292 4200 ext 125
NOTES
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Diversity, Invasive Species and Designing Invasion Resistant Communities
Kelly G. Lyons, PhD
Assistant Professor of Biology
One Trinity Place
Department of Biology
Trinity University
San Antonio TX 78212
(210) 999-8348
[email protected]
Human landscape disturbance has resulted in major changes to ecosystems. Due to the
concomitant loss of biodiversity and introduction of invasive species, there is intense interest in
how species loss may affect the susceptibility of communities to new species colonization.
Community species richness (the number of species) and composition (who is there) are
demonstrated to be important determinants of invasive species establishment and spread. Faced
with the task of improving habitats degraded through human land-use, there is now great interest
in the use of native species to restore ecosystems. In this talk I will discuss in general the
potential use of native species restoration as a tool to combat pest species invasions. I will then
present work in my laboratory designed to identify individual and suites of Texas native species
that can be used to restore native grasslands and will simultaneously serve to deter pest species
invasions.
Introduction
Due to unprecedented levels of resource extraction and land use combined with
boundless population growth, humans have altered virtually every ecosystem on the planet.
These activities have resulted in record losses in biodiversity (Pimm 1995). Indeed, it is now
estimated that 12% or all bird species, 23% of mammals, 25% of conifers, 32% of amphibians
and 52% of cycads are threatened with extinction (Baillie et al. 2004). Simultaneous with
species loss is the purposeful or accidental introduction of non-indigenous species. Most nonindigenous species act as minor components in a new landscape and require human input to
persist; however, a small but highly significant number escape and become invasive. In many
cases these species benefit from human ecosystem disturbance. In similar fashion to nonindigenous species, native species can develop into invasive pests through human land
management practices such as grazing or fire suppression. Invasive species are of great concern
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due to their threats to natural ecosystems; they are demonstrated to alter ecosystems by
displacing native species and homogenizing landscapes, disrupting food web relationships, and
altering disturbance regimes and nutrient cycles.
The increase in exotic species introductions coupled with native species extinctions has
prompted investigation into the role of diversity in community resistance to species invasion
(Levine & D’Antonio 1999 and Levine et al. 2002 and references therein). Results of numerous
small-scale, ecological studies consistently demonstrate that communities with more species are
less susceptible to invasion. The mechanism driving the relationship between diversity and
invasion is the subject of more recent investigations. In this talk I describe studies of the general
trends between diversity and invasion as well as studies of the mechanisms of competition
thought to determine this relationship. I then show how studies into the nature of the relationship
between diversity and invasion are being used to design invasion resistant communities for
grassland restoration.
Diversity and Invasion
Based on anecdotal observations of pest outbreaks and invasions in “simple” systems,
those of either naturally low or reduced diversity (e.g., islands and monospecific cultivations),
Elton (1958) concluded that such systems are more vulnerable to invasion. Small-scale
manipulative studies consistently support the view that lower diversity increases the
susceptibility of a community to invasion while large-scale observational studies typically
demonstrate the opposite trend (e.g., Stohlgren et al. 1999). In general, the negative trend
between diversity and invasion is more accepted as a reflection of the relationship between the
variables as large-scale observational studies are criticized for their failure to separate the
confounded effects of diversity and abiotic determinants of invasion success (Levine &
- 28 -
D’Antonio 1999).
Nonetheless, while the consistency of the relationship between diversity and invasion
among small-scale experimental studies is convincing, substantial differences in the amount of
variation in invasion are explained by diversity. For example, in an in situ, assembled
community study, Levine (2000) found that richness explained on average 15.3% of the
variability in invader fitness in a California riparian system. Among tall grass prairie assembled
communities, Naeem et al. (2000) demonstrated that diversity accounted for as much as 45% of
the variability in total above ground biomass of a non-indigenous species. Likewise, Stachowicz
et al. (1999) found that richness of a marine ecosystem accounted for 70.3% of the survivorship
of an invader. Employing a removal study, Lyons & Schwartz (2001) found that new species
colonization was explained by 32% of the variability in remaining richness. Ex situ studies,
however, have demonstrated less vigorous support. Using laboratory assembled microbial
mesocosms, McGrady-Steed et al. (1997) demonstrated with mixed results that introduced
species established only in low diversity treatments. Using grassland microcosms, Dukes (2001,
2002) found that treatments containing a single representative from each functional group
suppressed an NII species as well as treatments with more species per group.
As a determinant of ecosystem functioning, diversity is proposed to operate through a
variety of mechanisms such as niche partitioning and species complementarity (Hector et al.
2001, Levine & D’Antonio 1999, Prieur-Richard et al. 2000a). Where there are more species or
the natural species pool is intact there is a higher degree of niche partitioning and a more
thorough use of resources. It is anticipated that in ecosystems where resources are more limited
the system will be less open to invasion by new species. In addition, species loss is assumed to
result in open or “empty” niches (Herbold & Moyle 1986, Crawley 1987) and a release in
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resources (Davis et al. 2000) that can then be utilized by an introduced species. Indeed, species
rich communities are demonstrated to be more productive (Tilman et al. 1997, 2001; Hooper et
al. 2005 and works cited therein) and retain more nutrients (Naeem et al. 1994, Naeem et al.
1996) than species poor communities. A second mechanism, referred to as the sampling effect
(Loreau 2000, Aarssen 1997, Huston 1997), has been suggested to explain the relationship
between diversity and invasion. The sampling effect occurs because the probability of
encountering a significant competitor increases with increasing diversity. Current research
suggests that both species complementarity and the sampling effect explain the success of nonindigenous invasive species (Fargione & Tilman 2005).
Species Identity, Functional Groups and Invasion
Species diversity is consistently demonstrated to play a role in the invasion process on a
local scale; however, through these studies it has become apparent that species identity and
functional group identity can be more important determinants of invasion susceptibility than
diversity (Crawley et al. 1999). A functional group consists of species that utilize resources in
similar fashion. For example, warm-season grasses are expected to utilize resources in a similar
way because they all have fibrous roots, relatively shallow rooting depths, and produce
photosynthetic biomass, flowers and fruits around the same time. In order to characterize
functional groups, the concept of niche differentiation in the use of resources in space and time is
used. It is now widely accepted that niche differentiation can explain species coexistence
(Fargione & Tilman 2005). Species of a similar functional group have little niche differentiation
and are expected to compete with one another more intensively than species that utilize resources
differently in space and time.
Currently, there is mixed support for the effect of resident functional groups on new
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species colonization. In a species removal study, Symstad (2000) demonstrates that, while
residential functional group richness was negatively correlated with invasion success, there was
only weak evidence that species of a resident functional group inhibited establishment of
colonizers of the same functional group suggesting that species complementarity had more
control on establishment than functional group identity. In contrast, Fargione et al. (2003) found
significant and consistent evidence that functional group identity was an important determinant
in new species establishment. The presence of species of a like functional group resulted in
significant negative effects on the focal colonizing species. For example, non-legume forbs
inhibited other non-legume forbs more than any other functional group. Notably, C4 grasses
were demonstrated to have a stronger negative impact on cover of colonizers, regardless of
functional group, than any other resident functional group. Dukes (2002) found similar results
among two species of the Asteraceae in California annual grasslands. Among eight species,
Hemizonia congesta ssp. luzulifolia (Asteraceae) proved to have the most suppressive effect on
Centaurea solstitialis (Yellow Starthistle). Dukes (2002) suggests that this suppressive effect
was likely due to the fact that both species were summer-active annual forbs. It important to
note that overlap in functional group identity can have facilitative effects on new colonizers. In
an old-field study in France, Prieur-Richard et al. (2000b) demonstrated that the presence of
legumes had a net positive effect on the fitness of two NII species of the Asteraceae. While the
mechanism was not explicitly tested, it is assumed that the presence of the legumes resulted in a
more positive soil nitrogen status that facilitated growth of the colonizing species.
Native Species Restoration and Pest Species Establishment Success and Fitness
Extensive time and effort has been invested in the development of agricultural “cover
crops” to reduce the impact of weed species and improve soils quality (e.g. Carrera et al. 2004).
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Unlike agricultural ecosystems in which both the crop and the cover crop species are likely to
have large abiotic requirements, the establishment and maintenance of native species putatively
requires less input in the long run, provided certain land management approaches are employed.
Due to the fact that invasive species now foil many of our attempts to preserve wildlands,
managers are often required to focus on the dual goals of native species re-establishment and
pest species control. The relative ease of establishment of many native species combined with a
general need for native species restoration and the negative aspects of herbicide application make
the use of native species in invasive species management appealing.
Evidence that establishment of native species might be effective in serving to control pest
species is mounting. At the LBJ Wildflower Center (LBJWC) in Austin, TX, Mark Simmons
(restoration ecologist) has investigated the use of the Texas native Gallardia pulchella (Indian
Blanket) to control the non-indigenous invasive Rapistrum rugosum (Brassicacea) on roadsides
(Simmons 2005). The effect of G. pulchella on the fitness of R. rugosum was mixed and
competition appeared to occur primarily at the seedling stage; however, there was strong
evidence that, under certain conditions, G. pulchella would be effective in suppression of the
pest species. It is important to note that Simmons (2005) also found that G. pulchella may have
competitive or allelopathic effects on other native species (e.g., Lupinus texensis), thus reducing
their presence as well as their potential effect on the pest species.
In work similar to Simmons, Murphy (2005) found that Sanguinaria canadensis
(Papaveraceae) may be effective in control of Alliaria petiolata (Brassicaceae) in fragmented
forests. Likewise, Reever-Morgan & Rice (2005) demonstrated that older stands of Nassella
pulchra (Purple Needlegrass), a native perennial bunchgrass widely used in restoration in the
Central Valley of California, effectively reduces the fitness of C. solstitialis in grasslands
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dominated by invasive annual species. The results of their study also suggest that native and
non-indigenous invasive species are in competition due to overlapping use of soil profiles.
Finally, in an old field in the Cedar Creek Natural History Area in Minnesota, Blumenthal et al.
(2005) found that weed biomass was significantly lower in 6-year-old restored prairie as
compared to non-restored old fields. The study further suggests that competition for resources
drives weed species success as addition of nitrogen to restored plots reduced the suppressive
effect on the weed species.
Applying What We Know - Designing Invasion Resistant Communities
In my laboratory we are conducting research to identify Texas native species and suites
of Texas native species that will be effective for controlling non-indigenous and native invasive
species in rangelands of the Texas Hill Country. We are currently focusing on three pest species.
These include: Bothriochloa ischaemum (BI, KR Bluestem, Poaceae), Solanum elaeagnifolium
(SE, Silverleaf nightshade, Solanaceae), and Ratibida columnaris (RC, Mexican hat,
Asteraceae). SE and RC are native to North America and are found in rangelands throughout
much of the Southwest. Both are notorious rangeland pests. As with many pest species in
heavily grazed habitats, these native species are avoided by cattle and therefore increase under
grazing pressure. SE is considered a noxious weed throughout much of the U.S. Southwest
(USDA, NRCS Plants Database). It is a small (30-100 cm) herbaceous plant that spreads by seed
and rhizomes. All parts of the plant are toxic to ungulates (Diggs et al. 2000). RC is a native
perennial that has a dual reputation as an attractive wildflower and a rangeland pest, the latter
due to the fact that it provides poor forage (Ragsdale & Welch 1914). The plant grows 20-120
cm tall (Diggs et al. 2000) and is highly variable in growth form and flower color (K. Lyons,
pers. obs.). BI is a non-indigenous invasive C4 grass introduced from Europe and Asia that is
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both revered and cursed in this region (K. Lyons, pers. obs.). Beginning in the 1950s, pastures in
the Texas Hill Country, among many other areas of Texas, were seeded with BI (Amos &
Gehlbach 1988). In addition, for many years it has been seeded by the Texas Department of
Transportation for re-vegetation along highways (Northcutt 1993). The species is now
ubiquitous in fields and along roadsides in Central Texas. Although BI was initially used to
improve rangelands it is by many now recognized as a pest due to its prostrate growth form
under grazing pressure, susceptibility to winter kill (Webb 1991), high demand for soil
amendments, and homogenization of grasslands resulting in a decrease in forage for hunted
species (M. Simmons, LBJ Wildflower Center, pers. comm.). Grassland communities dominated
by BI are demonstrated to have lower rodent diversity than communities dominated by native
species (Sammon & Wilkins 2005). Diggs et al. (2000) describe it as a “pernicious weed
crowding out native species.”
In fall 2005 we established an experimental site in Waring, Texas, in which we planted
monocultures of 30 native and the three pest species to determine how well each establishes and
grows in the area and to collect baseline data on the traits of each species. We have collected
information on the following traits for each of the 19 species that have established in our plots:
germination rates, flowering and fruiting phenologies, above and below ground biomass, height
and depth, leaf thickness. In this talk I will discuss how this data will be used to design and test
invasion-resistant communities that can be used in restoration in the Texas Hill Country.
References
Aarssen, L.W. (1997). High productivity in grassland ecosystems: Affected by species diversity
or productive species? Oikos 80:183-184.
Amos, B.B., Gehlbach, F.R. 1988. Edwards Plateau Vegetation: Plant Ecological Studies in
Central Texas. Baylor University Press, Waco, TX.
- 34 -
Baillie, J.E.M., Hilton-Taylor, C., Stuart, S.N. (eds.) 2004. IUCN Red List of Threatened
Species: A Global Species Assessment. IUCN, Gland, Switzerland.
Blumenthal, D.M., Jordan, N.R., Svenson, E.L. 2005. Effects of prairie restoration on weed
invasion. Agricultural Ecosystems & Environment 107: 221-230.
Carrera, L.M., Abdul-Baki, A.A., Teasdale, J.R. 2004. Cover crop management and weed
suppression in no-tillage sweet corn production. HortScience 39(6): 1262- 1266.
Crawley, M.J. 1987. What makes a community invasible? In: Colonization, Succession and
Stability eds. Gray, A.J., Crawley, M.J., Edwards, P.J. Blackwell Scientific Publications,
Oxford.
Crawley, M.J., Brown, S.L., Heard, M.S., Edwards, G.R. 1999. Invasion-resistance in
experimental grassland communities: species richness or species identity? Ecology
Letters 2: 140-148.
Davis, M.A., Grime, J.P., Thompson, K. 2000. Fluctuating resources in plant communities: a
general theory of invasibility. Journal of Ecology, 88, 528-534.
Diggs, G.M., Lipscomb, B.L., O’Kennon, R.J. 2000. Shinner & Mahler’s Illustrated Flora of
North Central Texas. Botanical Research Institute of Texas, Fort Worth, TX.
Dukes, J.S. 2001. Biodiversity and invasibility in grassland microcosms. Oecologia 126: 563568.
Dukes, J. S. 2002. Species composition and diversity affect grassland susceptibility and
response to invasion. Ecological Applications 12(2): 602-617.
Elton, C.S. Ecology of Invasions by Animals and Plants. 1958. Methuen, London.
Fargione, J., Brown, C.S., Tilman, D. 2003. Community assembly and invasion: An
experimental test of neutral versus niche processes. Proceedings of the National
Academy of Science 100(15): 8916-8920.
Fargione, J.E., Tilman, D. 2005. Diversity decreases invasion via both sampling and
complementarity effects. Ecology Letters 8: 604-611.
Hector, A., Dobson, K., Minns, A., Bazeley-White, E., Hartley-Lawton, J. 2001. Community
diversity and invasion resistance: An experimental test in a grassland ecosystem and a
review of comparable studies. Ecological Research 16:819-831.
Herbold, B., Moyle, P.B. 1986. Introduced species and vacant niches. American Naturalist
128: 751-760.
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Hooper, D.U., Chapin, F.S., Ewel, J.J., Hector, A., Inchausti, P., Lavorel, S., Lawton, J.H.,
Lodge, D.M., Loreau, M., Naeem, S., Schmid, B., Setala, H., Symstad, A.J., Vandermeer,
J., Wardle, D.A. 2005. Effects of biodiversity on ecosystem functioning: A consensus
of current knowledge. Ecological Monographs 75(1): 3-35.
Huston, M.A. 1997. Hidden treatments in ecological experiments: re-evaluating the ecosystem
function of biodiversity. Oecologia 110: 449-460.
Levine, J.M. 2000. Species diversity and biological invasions: relating local process to
community pattern. Science 288: 852-854.
Levine, J.M., D’Antonio, C.M. 1999. Elton revisited: a review of the evidence linking diversity
and invasibility. Oikos 87: 15-26.
Levine, J.M., Kennedy, T., Naeem, S. 2002. Neighbourhood scale effects of species diversity
on biological invasions and their relationship to community patterns In
eds. Loreau,
M. Naeem, S., Inchausti, P. Biodiversity and Ecosystem Functioning: Synthesis and
Perspectives, Oxford University Press, Oxford.
Loreau, M. 2000. Biodiversity and ecosystem functioning: recent theoretical advances. Oikos
91: 3-17.
Lyons, K.G., Schwartz, M.W. 2001. Rare species loss alters ecosystem function – invasion
resistance. Ecology Letters 4(4):358-365.
McGrady-Steed, J., Harris, P.M., Morin, P.J. 1997. Biodiversity regulates ecosystem
predictability. Nature 390:162-165.
Murphy, S.D. 2005. Concurrent management of an exotic species and initial restoration efforts
in forests. Restoration Ecology 13(4): 584-593.
Naeem, S., Thompson, L.J., Lawler, S.P., Lawton, J.H., Woodfin, R.M. 1994. Declining
biodiversity can alter the performance of ecosystems. Nature 368: 734-737.
Naeem, S., Håkansson, K., Lawton, J.H., Crawley, M.J., Thompson, L.J. 1996. Biodiversity and
plant productivity in a model assemblage of plant species. Oikos 76: 259-264.
Naeem, S., Knops, J.M.H., Tilman, D., Howe, K.M., Kennedy, T., Gale, S. 2000. Plant
diversity increases resistance to invasion in the absence of covarying extrinsic factors.
Oikos 91: 97-108.
Northcutt, P. 1993. A Practical Guide to the Establishment of Vegetative Cover on Highway
Rights-of-way. Landscape Section, Division of Maintenance and Operations, Texas
- 36 -
Department of Transportation, Austin, Texas.
Pimm, S.L., Russell, G.J., Gittleman, J.L., Brooks, T.M. 1995. The future of biodiversity.
Science 269: 347-350.
Prieur-Richard, A.H., Lavorel, S. 2000a. Invasions : the perspective of diverse plant
communities. Australian Journal of Ecology 25: 1-7.
Prieur-Richard, A.H., Lavorel, S., Grigulis, K., Dos Santos, A. 2000b. Plant community
diversity and invasibility by exotic invasion of Mediterranean old fields by Conyza
bonariensis and Conyza canadensis. Ecology Letters 3: 412-422.
Reever-Morgan, K.J., Rice, K.J. 2005. Centaurea solstitialis invasion success is influenced by
Nassella pulchra size. Restoration Ecology 13(3): 524-528.
Sammon, J.G., Wilkins, K.T. 2005. Effects of an invasive grass (Bothriochloa ischaemum) on a
grassland rodent community. Texas Journal of Science 57(4): 371-385.
Simmons, M. 2005. Bullying the bullies: The selective control of an exotic, invasive annual
(Rapistrum rugosum) by oversowing with a competitive native species (Gaillarida
pulchella). Restoration Ecology 13(4): 609-615.
Stachowicz, J.J., Whitlatch, R.B., Osman, R. W. 1999. Species diversity and invasion resistance
in a marine ecosystem. Science, 286, 1577-1579.
Stohlgren, T.J., Binkley, D., Chong, G.W., Kalkhan, M.A., Schell, L.D., Bull, K.A., Otsuki, Y.,
Newman, G., Bashkin, M., Son, Y. 1999. Invasive plant species invade hot spots of
native plant diversity. Ecological Monographs 69:25-46.
Symstad, A.J. 2000. A test of the effects of functional group richness and composition on
grassland invasibility. Ecology 81: 99-109.
Tilman, D., Lehman, C.L., Thomson, K.T. 1997. Plant diversity and ecosystem productivity:
theoretical considerations. Proceedings of the National Academy of Science 94: 18571861.
Tilman, D., Reich, P.B., Knops, J., Wedin, D., Mielke, T., Lehman, C. 2001. Diversity and
productivity in a long-term grassland experiment. Science 294:842-845.
Webb, D. 1991. Old World Bluestem Conference Proceedings. Circular E. Oklahoma State
University Cooperative Extension Service.
Copyright © 2006 by Kelly G. Lyons.
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Butterflies and Native Plants of South Central Texas
Bill Lindemann
884 Loudon Road
Fredericksburg, Texas 78624
(830) 997-8917
[email protected]
Native plants and butterflies are both on the low end of the natural food chain; however,
over many millennia each has had to continue to evolve defenses to survive--plants fending off
the voracious butterfly larvae and the butterflies in turn keeping their predators at bay. This
struggle for survival between plants and butterflies has been going on for roughly a hundred
million years.
It is interesting that butterfly and moth species seem to have divided the plant kingdom,
with each butterfly or moth family selecting a plant family member to be the larval food source
for its respective family. Imagine the consequences for a plant if all of the butterflies and moths
chose the same plant family as their host plant--extinction of both would be imminent. Often a
species of butterfly or moth will depend on a single plant species for its food source and ultimate
survival. Examples include the Monarch butterfly who depends solely on milkweeds, or the Gulf
Fritillary who depends on members of the passion vine family for survival. In nature there are
always exceptions--the Gray Hairstreak butterfly utilizes 50 species of plants. Through time,
both plants and butterflies have been able to adapt successfully to the assaults of climate.
With these facts in mind, we are going to look at the rather unique dual development of
both plants and butterflies as they evolved in order to survive. We will also look at the other
factors that play significant roles in determining the diversity of butterflies for an area such as the
South Central Texas Region. But first it will be helpful to look at the biological aspects of the
butterflies as they relate to plants.
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Butterfly and Plant Biology and Ecology
First, where do the butterflies fit into the animal kingdom? They belong in the animal
kingdom--part of the phylum Arthropoda, class Insecta and order Lepidoptera, which is
subdivided into two superfamilies and six families in North America. Applying a few numbers,
more than 17,000 species of butterflies are known worldwide with many still remaining
unknown to science. There are more than 750 species known to occur in North America with
more than half of those being found in Texas. In Bexar County and South Central Texas, the
current total stands at 184 species. Keep in mind that these numbers are probably incomplete
because of the limited numbers of experts trying to find them; therefore, having slightly fewer
than half of the state total in this area implies significant diversity. We will also examine the
factors involved with this excellent diversity.
Let’s look at the order Lepidoptera. This order also contains moths, and moths
significantly outnumber butterflies at any level one might choose. For example, in North
America more than 10,500 species are known to science. How do you tell the difference between
a butterfly and a moth? Both have similar life cycles, which is why they are in the same family.
Butterflies are predominantly day fliers and generally have narrower bodies. Both have antennae,
but butterflies have knobs or clubs on their terminal ends. Moths, on the other hand, are mainly
night fliers, have thicker bodies and have thread- or feather-like antennae. Some moths spin
silken cocoons in which the larvae change to adults; butterflies form chrysalises in which they
conduct this change.
Another difference between butterflies and moths is that butterflies are generally much
more colorful than moths. As moths are night fliers, they need to hide during the day from
potential predators; therefore, their colors are more subtle earth tones that blend in with bark,
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leaves and other refuges to avoid detection. Butterflies use their colors to blend in with the colors
of the flowers on which they feed. Additionally, in the larval stage, moth caterpillars often are
more hairy than their butterfly counterparts.
The life cycle of the butterfly and moth members of the order Lepidoptera have four
stages. After mating, the female searches for a suitable host plant for her progeny. As I
mentioned, the females must find the one plant species or possibly several species in a plant
family on which to lay their eggs. Some butterflies have sensors in their front legs that can detect
the required chemicals in a plant their larvae will need to survive. Once the larva hatches, its life
is an eating frenzy. After the larva reaches maturity, it finds a hiding place to pupate--changing
into a chrysalis that hangs by a thread. What happens inside the chrysalis is one of nature’s
neatest magical tricks. Going in as a beastly looking character and emerging as a beautiful
butterfly is an enduring theme in myth and literature.
Unfortunately most adult butterflies live for only two weeks or so; they lead hectic short
lives with the main objective being to mate. The butterfly does not necessarily feed on the host
plant or any single plant. During its lifetime the butterfly feeds on nectar, decaying animal and
plant tissue, and/or animal dung. Once mated, the adult lives its life out, either expiring or
becoming part of the food chain.
Those of you who are familiar with monarchs know that they migrate long distances to
wintering grounds in Mexico and along the California coastline; therefore they live longer than
two weeks. The last brood of the monarch’s breeding season delay their production of hormones
that drive the mating process; therefore their lives are extended for several months. As they
return from their wintering sites, the reproduction hormones develop, setting the two-week
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lifetime clock. Once these hormones are produced, the female has two weeks to mate and lay
eggs. Each succeeding brood then continues the trek northward.
Some other butterflies migrate, but not the long distances monarchs do; however, many
can wander for long distances in search of a mate. Those of us who live in the Central Texas area
have just experienced an onslaught of literally billions of American snout butterflies moving
northward from the Lower Rio Grande Valley area. These mass movements generally follow
drought periods. Most of the snouts were males searching for mates.
I would like to spend some time discussing the evolution of defense tactics between
native plants and their consumers. These are a few facts about the relationship between
butterflies and native plants. Butterfly larva feed mainly on flowering plants. Interestingly, the
fossil record suggests that some 100 million years ago, butterfly larvae fed mainly on the legume
family. Over time these butterfly larvae spread their preferences to more than 120 families of
plants; however, each butterfly species feeds on one specific species of plants or on a close
family relative. These feeding relationships require thousands of years to develop, which is the
reason butterfly larvae mostly ignore non-native plants.
To survive the waves of leaf-munching caterpillars, the plants had to develop defense
strategies to ward off the invaders. To defend themselves, the plants developed tough skins,
spines, resins, silica, and gums. They also produced chemicals for defensive purposes. These
plants produced alkaloids, steroids, glycocides, tannins, and other chemicals to thwart the larvae.
Some conifers even developed chemicals to mimic the larval molting hormones: The saying that
“all’s fair in love and war” seems to apply here. Other plants evolved chemicals to inhibit
digestion.
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When all else fails, the plants must rely on the predators of the larvae to come to their
defense. As part of the food chain, the butterfly larvae have a host of predators, such as
parasitoids, birds, and other insects. Nature has a number of ways to balance the supply and
demand for food, making sure that all living things have something to eat. When this fails,
species become extinct.
The butterflies had to develop their own defense system to survive. First they had to
develop anti-toxins to neutralize the chemical warfare tactics used by the native plants. By
neutralizing these potential harmful chemicals, the larvae could continue to consume their
adopted host plants. As butterflies honed their defenses, they developed sensors that could detect
and trace the toxins used by the plants.
One advanced tactic used by the butterflies was to turn the plant’s toxin into a feeding
stimulant, thereby turning the tables on the plants. Other butterflies, such as the monarch,
developed a tactic of storing the plant’s toxins in their bodies to defend themselves from their
own predators. When eaten by a bird predator, the chemicals used by the milkweeds causes the
bird to throw up the swallowed butterfly. The birds eventually learned to avoid these unsavory
insects. Other insects began to mimic the toxin laden butterflies to avoid bird predation.
Native plants supply the adult butterflies with food nutrients through plant nectar. Flower
nectar can contain as much as twenty per cent sugar, providing energy needed by the butterflies.
Butterflies prefer low sugar nectars, thereby avoiding competition with the bee family that
prefers high sugar nectars. Native plants also can supply nutrients through sap and fruit. A
number of butterflies can be found feeding on rotting fruits.
Plants are not the complete source of foods for some butterflies. Butterflies also derive
food and nutrients from animal waste products, carrion, decaying wood, aphid honeydew, and
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muddy soils. These butterflies use their proboscises (tongues) to extract the nutrients from the
different food sources, including nectar.
Adult butterflies do have preferences for flower colors; however they also use ultraviolet
light to guide them to certain favored flowers. Butterflies with a long proboscis are able to feed
on tubular flowers, while those with a short proboscis must feed on the shallow flowers.
Families of Butterflies
The following is a quick introduction to the various families grouped under the two
superfamilies of butterflies: the Papilionoidea, the scudders; and the Hesperioidea, the skippers.
Scudder is a name used by butterfly author James Scott to replace the term of “true butterflies.”
Skippers are smaller, quicker, less colorful butterflies that are hard to see, much less to identify.
The Papilionoidae in Texas are sub-divided into five families: the swallowtails, whites
and sulphurs, the brushfoots, snouts, and gossamer-wings.
Swallowtails: Large colorful butterflies with tails; flutter while feeding; rest with open wings;
larval food includes pipevines, parsleys, annonas, laurels, and citrus.
Whites and sulphurs: White and yellow colors; rest and feed with closed wings; overwinter in
pupa stage; larval foods include mustards (whites) and legumes and caltrops (sulphurs).
Brushfoots: Very diverse family including satyrs, milkweeds, checkerspots, crescents, leafwings,
longwings, admirals, and emperors; short front legs with chemical sensors; very colorful; great
diversity in appearance; mimicry common; larval food plants include milkweeds, aniscanths,
hackberries, asters, spurges, oaks, grasses, and many more families.
Snouts: One genus; snout-like appendage; wings always folded; larval food is spiny hackberry.
Some scientists place this family with the brushfoots.
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Gossamer-wings: Includes metalmarks, hairstreaks, and blues; small; underwings patterned;
upperwings iridescent (often blue); larval food includes oaks, legumes, sumacs, and mallows.
The Hesperidae in Texas are subdivided into two families, the skippers and the giant
skippers, with most of the species in the skipper family.
Skippers: More than 200 species in Texas; small stout bodies; subtle earth colors with weak
patterning; feed with wings closed to partially open (upper wings appear as “tail-fins); some
species have long tails; fast erratic fliers; subtle differences make identification difficult; larval
foods include many species of grasses.
Giant skippers: Seven species in Texas; larger than other skippers; desert inhabitants; difficult to
observe; larvae bore into host plant agave and yucca roots.
Range and Distribution of Plants and Butterflies
From a broad point of view the distribution of butterflies in Texas is closely tied to the
ranges of larval host plants and humidity. Focusing on individual butterfly species, the
represented populations need a favorable set of natural resources to survive: favorable
temperature range, suitable food plants for egg laying, nutrition for both larvae and adults,
relatively safe night perches for adults, and sites for pupation. Each stage of a butterfly’s life is
subject to natural events, such as droughts and freezes, over which the butterflies have no
control. Vegetation density (shading), altitudes, humidity, soil types, and drainage conditions can
also influence butterfly distributions and population numbers. The Central Texas Region falls
into a transition zone of both precipitation and mean temperature extremes. East Texas receives
more than 50 inches of annual rainfall compared to less than 10 inches in the far western area of
the state. Likewise, mean temperature ranges from a low of 56 degrees (F) in the Texas
Panhandle to 74 degrees (F) in the Lower Rio Grande Valley.
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Within the transitional central Texas region, annual fluctuations in the temperature and
precipitation impacts both plants and butterflies; however, plants have a higher tolerance to
survive periods of droughts and freezes than do butterflies. This central region of the state can be
perceived as a great mixing bowl of the flora and fauna that enter the state from larger
ecosystems.
East Texas is the western edge of the lush pine-hardwood forests of the southeastern
region of the United States, while the far western part of the state is the eastern edge of the
Chihuahuan Desert and mountain region. Similarly, the flora in the southern part of the state
represent the northern edge of the sub-tropical vegetation zone of Mexico, while the northern
part of the state marks the southern edge of the Great Plains prairies. Add to this mix the coastal
prairie region bordering the Gulf of Mexico and the result is an extremely varied flora. With the
flora comes the associated butterfly species, giving Texas the highest number of different
butterfly species in the country.
The south central area of Texas, which includes the city of San Antonio, is an area of
convergence of four of the Texas ecosystems, a convergence that produces an interesting
diversity of native plants. The western half of the area can be split into two halves, the northern
(Edwards Plateau) and the southern (South Texas Brushlands) ecosystems. The eastern half is a
much more complex mixture of ecosystems. Included in the mix are the Llano Uplift, the
Blackland Prairie, and the Post Oak Savannah ecosystems. The eastern area soils support a
diverse flora developed in deciduous woodland, prairie, and savannah habitats.
The butterfly distribution in the western half is influenced by species whose ranges
mostly extend from the west and southwest into this area and is dominated by the whites and
sulphurs family. A minor number of skipper species from the north and northwest can be found
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here. The richest butterfly diversity corresponds to the tropical woodlands associated with
increased river activity, dry subtropical forest and scrub, and savannah habitats. The skippers
have the largest representation of species in this area. It is interesting that there is little endemism
in this area. Possible explanations would be the climatic fluctuation and that many species’ range
limits occur in this area.
Butterfly Gardening
If you want to grow a garden for butterflies, the first hurdle is to prepare yourself
psychologically to deal with those pesky caterpillars that want to eat your garden. Keep in mind
to prepare for the beauty of the adult butterfly requires that you set the table for the “beasts.”
Make sure that you include the host plants for the larvae of the butterflies you want to attract.
Although butterflies are prone to wander, most tend to say in the area where they were raised
because they must depend on the availability of host food plants for their young.
Planting only nectar plants will not produce the variety of butterfly species that gardeners
might have in mind. Set a great table of larval host plants, and the butterflies will come. In
addition to larval host food and nectar plants, consider keeping an area where rotting fruit can be
placed to attract those species that feed only on this food source. There are recipes for
concoctions of ripe fruit, beer, and molasses that can be placed in containers around your garden
to satisfy hungry adult butterflies that prefer this food source.
I would recommend that you purchase Geyta Agilvsgi’s book on butterfly gardening. It is
an excellent resource book on butterflies. For identification purposes, I would recommend Jim
Brock and Kenn Kaufman’s book on the Butterflies of North America. Raymond Neck has a
book on the butterflies of Texas. John and Gloria Tvetan have a great book on the butterflies of
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the Houston area. As with bird books, as the sport of butterfly watching increases, so will the
books on butterflies.
Bibliography
Ajilvsgi, Geyata, 1990, Butterfly Gardening for the South, Taylor Publishing Company, Dallas,
Texas, 348 p.
Brock, Jim P. and Kaufman, Kenn, 2003, Butterflies of North America, Houghton and Mifflin,
New York, New York, 384 p.
Gaskin, David E., 1998, “Butterflies of the Upper Frio-Sabinal Region, Central Texas, and
Distribution of Faunal Elements Across the Edwards Plateau,” Journal of Lepidopterist’s
Society, Vol. 52, pp. 229-261.
Neck, Raymond, 1996, A Field Guide to Butterflies of Texas, Gulf Publishing Company,
Houston Texas, 323 p.
Scott, James A., 1986, The Butterflies of North America, Stanford University Press, Stanford,
California, 583 p.
Tvetan, John and Gloria, 1996, Butterflies of Houston and Southeast Texas, University of Texas
Press, Austin, Texas, 292 p.
Copyright © 2006 by Bill Lindemann.
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¿Quién es Mas Macho?
Paul Cox
Assistant Superintendent
San Antonio Botanical Garden
San Antonio/Bexar County marks the nexus of four of Texas’ ten different vegetational
regions: the Blackland Prairie, the Edwards Plateau, the Post Oak Savannah, and the South Texas
Plains. Many exotic plants have been introduced here to bring different ornamentals to our
rugged area. Given our difficult soils and climate, most have been unable to successfully
compete with the outstanding natives. The few that have thrived have gone on to become
noxious pests. During the last thirty years we have seen the weather fluctuate dramatically.
There have been record cold, wind, floods and freezes. This has culled out many exotics and
favored the natives which have grown up with these extreme conditions. Let us review some of
the natives that have proven themselves to be ‘mas macho” in their performance over the long
haul.
Trees
1.
Live oak (Quercus virginiana). A stalwart evergreen tree growing to immense
proportions. Although it is threatened by the dread oak, this can largely be avoided by using
sound horticultural practices such as proper pruning and painting of cut wounds. It is found in
all four areas and is one of our most revered trees, with many large specimens marking our
historical events.
2.
Bur oak (Q. macrocarpa). Sweeping down from the Blackland Prairies, it has often been
called the aristocrat of trees. Its acorn (the largest in North America), large leaves, rugged life
style, and resistance to oak wilt have made these trees a favorite shade tree.
3.
Pecan (Carya illinoensis). Our state tree’s nuts are consumed by almost every species of
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wildlife, including us. It is a formidable shade tree.
4.
Anaqua (Ehretia anacua). This is one of the few trees that have retained their native
Indian names. German settlers referred to them as “Vogel Barren Bauml,” or “bird berry tree,”
because of song birds’ affinity for the pea-sized yellowish fruits. Its sandpaper leaves were used
by woodcrafters to finish off wooden carvings. Kids call it the “Aggie toilet paper tree.”
5.
Mexican ash (Fraxinus berlandieri). Villified as a “weed” tree due to its over-planting
during the 1950’s, it can actually be a responsible specimen if grown in lean conditions.
6.
Sycamore (Platanus occidentalis var. glabrata). The native sycamore, variety glabrata,
does much better than its eastern cousin due to drought tolerance and resistance to anthracnose.
7.
Texas red oak (Q. buckleyi). This fast-growing tree has good fall color. Oak wilt can be
avoided with good horticultural practices.
8.
Chinkapin oak (Q. muhlenbergi). Good growth rate and attractive foliage make it one of
our most handsome natives. The chinkapin tolerates a wide variety of sites.
9.
Wild olive (Cordia bosseri). Large leaves and white flowers give it an exotic look, and it
offers superb drought tolerance.
10.
Bald cypress (Taxodium distichum). This is nearly an aquatic tree in nature, but it can
tolerate drier sites with proper care. Its longevity and size make it one of our most interesting
trees. It represents a link between the eastern and southern species.
11.
Rusty black haw (Viburnum rufidulum). This tree displays outstanding for its fall color,
spring flowers, and blue summer fruit.
12.
Carolina buckthorn (Rhamnus caroliniana). These trees offer nice glossy leaves and
attractive fruit.
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Shrubs
1.
Mexican buckeye (Ungnadia speciosa). Pecan-like leaves turn yellow for fall, and early
spring pink flowers followed by attractive pods add up to one of our most attractive natives.
2.
Texas mountain laurel (Sophora secundiflora). This shrub is such a staple in the nursery
trade it is now considered “mainstream.” Evergreen foliage and scented purple flowers make it
very popular.
3.
Cenizo (Leucophyllum frutescens). Another “mainstream” native that offers a cultivar for
every occasion. Available in a variety of flower colors and shrub sizes, it is now our official
native state shrub.
4.
Evergreen sumac (Rhus virens). Dark green leaves and attractive red fruit make it a
standout.
5.
Red and yellow buckeyes (Aescules pavia and var. flavescens). Their offset life cycle
provide plentiful interest in the landscape.
6.
Esperanza (Tecoma stans). Usually a woody perennial, this shrub is at the northeast edge
of its natural range here in Bexar County.
7.
Hummingbird bush (Anisacanthus wrightii). Hummingbirds are fond of it, and the
crimson patch butterfly lives off of it.
8.
Autumn sage (Salvia greggii). Hummingbirds are attracted to the flowers, and it is now
offered in a wide variety of colors. This is one of our landscape stalwarts.
9.
Barbados cherry (Malpighia glabra). At the northern edge of its range in Bexar County,
this evergreen shrub bears attractive flowers and appealing red fruit and shears well into a nice
hedge.
10.
Rock rose (Pavonia lasiopetala). It has showy two-inch pink flowers over a long
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blooming period, and ss its name implies, it is very drought tolerant.
11.
Spanish dagger (Yucca treculeana). This bold accent specimen has spine-tipped leaves
that should be kept away from areas of foot traffic. . This poster child for Creationists is very
drought hardy.
13.
Prickly pear (Opuntia species). The spineless form of this cactus is the most user
friendly.
Vines
1.
Scarlet clematis (Clematis texensis). This vine is parent to many of our gaudy nursery
hybrids.
2.
Agdestis clematidae. Fragrant fall flowers and huge storage root make it a novelty.
3.
Seven-leaf creeper (Parthenocissus heptaphylla). This well-behaved vine has good fall
color. The Maltsberger cutivar is quite reliable.
Assorted
1.
Cedar sage (Salvia roemariana). One of the prettiest of salvias, it is now on the market
with the name, Scarlet Trumpets.
2.
Red prickly poppy (Argemone sanguinia). Why isn’t it in cultivation? This one has
moved up from sandy soils in South Texas.
3.
Lindhelmer globe mallow (Sphearalcea lindheimeri). Another overlooked ornamental.
4.
Blackfoot daisy (Melampodium leucanthum). This one has moved down from the Hill
Country.
5.
Phlox Drummondi (Phlox drummondii). This was a European favorite before catching
on here.
6.
Clover fern (Marselia macropoda). Great groundcover.
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7.
Lindheimer’s muhly Grass (Muhlenbergia lindheimeri). One of our most popular native
grasses.
8.
Red flowered yucca (Hesperaloe parviflora). It would be difficult to name a more hardy
plant than this hummingbird magnet.
Copyright © 2006 by Paul Cox.
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Running Dry: Water and Development in San Antonio
Char Miller
Professor of History
Director of Urban Studies
Trinity University
One Trinity Place
San Antonio TX 78212-7200
210-999-7608
[email protected]
Water has had a profound impact on the physical development of San Antonio, Texas. Sited
along the banks of the San Antonio River which rises up out of springs associated with the
Edwards Aquifer, the community has long depended on these waters to sustain life. That was
true of the region’s indigenous peoples, whose semi-permanent settlements attracted the Spanish
to settle in the area. And so it has been ever since, from its eighteenth-century frontier origins to
the early twenty-first-century sprawled size, San Antonio has used these waters to power its
growth. But the aquifer’s limits, when combined with the city’s population boom, and its
northerly spread across the aquifer’s recharge and drainage systems, along with the area’s
periodic (and crippling) droughts, have raised serious questions about the future sustainability of
San Antonio’s water supplies, and thus of the city itself.
If, as a popular T-shirt asserts, “Golf is Life,” then there is a lot of living going on in the
American Southwest. Climate is essential to understanding the vital link between the game and
the region. Texas, New Mexico, and Arizona--the three principal southwestern states--benefit
from an excess of 300 days of sunshine, which is conducive to year-round play. The salubrious
weather is a particular inducement for those who live in more northerly and colder climes to head
south and west for a winter round or three, just as it has encouraged the migration of millions of
elderly Americans, many of whom have packed their clubs and followed the sun to retirement
homes located in the Yuma desert, the Rocky Mountains, or the Rio Grande Valley. Whatever
the purpose or destination of this travel, it has been financed by a surge in American’s disposable
income since the 1970s that has underwritten the tremendous growth in the regional recreational
and tourist infrastructure. This buildup has been nourished, too, by the vast, post-World War
Two federal investment into the construction of an interlocking complex of dams, reservoirs, and
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water-distribution systems throughout Arizona and New Mexico, and, to a lesser extent, Texas.
Without ready access to water, (and, not unrelatedly, to air conditioning) the region could not
sustain the explosion of its urban populations, which has resulted in Houston, Phoenix, Dallas,
and San Antonio joining the list of the nation’s ten largest cities.
Not all citizens of the Southwest drive, chip, and putt, but that is not due to any lack of
fairways, bunkers, or greens. Capitalizing on the region’s Sunbelt image, demographic
transformation, and increased income levels, developers have built a staggering number of golf
courses, most of which are tightly clustered around the fast-growing cities. Arizona claims 351
courses, New Mexico another 95, and Texas boasts upwards of 900. Often laid out within highend subdivisions, neatly tying together housing, recreation, and other luxe amenities, the wellwatered courses have spawned a slew of secondary commercial activity. No wonder urban
boosters tout the virtues of golf, for it has expanded local service economies even as it has
signaled the region’s shift out of its rural past into its suburban future. Founded in rain-swept,
fifteenth-century eastern Scotland, golf has become the game of a dry, twenty-first-century
American southwest.
No city takes this prospect more seriously than San Antonio. Home to 45 golf courses,
three of which are ranked in Golf Digest’s annual listing of the nation’s 100 Greatest Courses,
the south-central Texas metropolis is acclaimed as one of Golf Magazine’s Top 50 Worldwide
Golfing Destinations. Such stellar designations are much prized for the visitors they apparently
lure to town; these guests’ liberal spending habits have eased some of the economic pain brought
on by a sharp decline in Cold War-generated federal dollars that once streamed through the city’s
five major military bases. In San Antonio, tourism now pays the bills.
Little wonder, then that local business leaders, political mavens, and golf enthusiasts
- 54 -
were delighted by the news in early 2001 that the Professional Golf Association of America
(PGA) had teamed up with Lumberman’s Investment Group of Austin to build a sprawling 2800acre resort amid the rolling hills of northern Bexar County. The promise of two new golf courses
totaling 36 holes (with designs by golf legends Peter Dye and Jack Nicklaus), a golf-learning
center, as well as an up-scale 500-room hotel, ritzy shopping mall, and luxury housing, led Steve
Moore, executive director of the Convention and Visitors Bureau, to enthuse: “The economic
benefits are multifold. There would be the [public relations] and articles written about it and also
an increased interest by leisure visitors and corporate and convention visitors.” Even those who
would potentially compete with the new courses shared Moore’s faith that the PGA Village
“would have a positive impact to position San Antonio as a golf destination.” Courtney
Connally, Head Pro at the Fair Oaks Ranch club, noted that the city was a natural for the
proposed facility. “San Antonio really has a lot of attractions, the topography, the weather, and
the family festivities.” Those advantages were impressive, confirmed Jim Autry, PGA executive
director, and were what led his organization to select this site. San Antonio “is one of the top
cities in America. You’ve got a wonderful town.”1
It would become a conflicted city, too. As word spread about the new project, criticism
exploded. At the core of reactions was water, an issue that has long been close to the surface of
the community’s political life. “How wonderful! A 36-hole golf course!” exclaimed Patricia
Coleman, a citizen of nearby New Braunfels, Texas in a letter to the San Antonio Express-News.
“A 500-room hotel full of guests, all taking 30-minute showers. Fairway homes with lawns and
gardens well above the price that the average citizen can afford, each with a minimum of 2 ½
baths, no doubt, and all over the Edwards Aquifer.” Satire melted into anger when she pointed
out that the region was entirely dependent on the aquifer for its potable water. Coleman was not
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alone when she prayed that “clearer heads will prevail when permits are sought for this illconceived pipe dream. We do not have the water to support this monstrosity.”2
In the succeeding months, local environmental groups analyzed the special taxing district
the state legislature and city council created for the project, gauged PGA Village’s political
support, and investigated its potential to harm the aquifer’s sensitive recharge features. Despite
assurances that the large resort would install a rigorous set of state-of-the-art environmental
protections to insure the maintenance of unsullied underground water, and that it would jumpstart the urban economy with new work and tourist dollars, a coalition of activist organizations
came together to challenge its construction. Two organizations with lengthy histories of
grassroots protest in the city, Communities Organized for Public Services (COPS, founded in
1974) and METRO Alliance (founded in 1982), joined with the newly created SmartGrowth
Coalition, to launch a petition drive to overturn the City Council’s support for PGA Village.
Their populist slogan—“It’s Our Money/It’s Our Water”—bore electoral fruit: by July 2002,
many more than the required 63,000 citizens had signed petitions, forcing a November 2002
special election. One month later, PGA Village backed out of the deal, citing the city's divisive
political atmosphere.3
This particular struggle over water and growth in San Antonio may be of very recent
origin, but it depends on a set of concerns about how best to live within this semi-arid region that
date back millennia. All those who have chosen to inhabit the San Antonio River valley have had
to take into account the flow of water beneath and across the land. Whatever the form of
settlement, and by whatever name the inhabitants called themselves, each group, from the
Tonkawa to the Spanish, the Mexicans to the Americans, has framed their collective destiny and
social structure around their capacity to draw upon available water supplies. It turns out that
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when early twenty-first-century San Antonians fought over fairways, hotels, and housing, they
were participating in an age-old drama.
A Spanish Mirage
Native American peoples had long exploited south Texas river valleys and creek beds,
where they had fished and harvested, foraged, and hunted. Archeological evidence dug up along
the tributaries of the San Antonio River, for instance, reveals the presence of hunter-gatherers
dating back more than 11,000 years. Those who inhabited these sites before the Spanish arrived,
known collectively as the Tonkawa, searched for “live” water (or that which flowed during the
hot summer months) by migrating along a series of south Texas rivers that cut down through the
Edwards Plateau. Known today as the Hill Country, this region marks the end of the Great Plains
defined by the Balcones Escarpment. Out of its rough valleys, in an arc from west to north, flows
the Nueces, Frio and Medina Rivers, the San Antonio, Guadalupe and Colorado; these latter two
run through present-day New Braunfels and Austin respectively. As the hunter-gatherers roamed
across this terrain, they made extensive use of the line of springs that bubbled up from the
limestone bedrock.4
As their physical movement suggests, they never deemed it necessary to manipulate the
regional waterscape to enhance food supplies. Unlike the Hohokam, who lived along the Salt
River in what is now southern Arizona, the Tonkawa apparently did not put stick to ground to
build channels through which to maneuver stream flow and irrigate crops. Or rather they did not
do so of their own accord. But by the late-seventeenth and early-eighteenth centuries, facing
intense pressure from two invading forces, they at once chose and were compelled to give up
their indigenous ways, and learned to live within the south Texas environment in a new manner.5
Spanish missionaries pressing up from the south, brought with them diseases that
- 57 -
decimated indigenous populations; it was at the missions they subsequently established along the
San Antonio River Valley that many of the surviving Indians, often through forced conversion,
were transformed into agricultural laborers.
The arrival of the Lipan Apache, who came to dominate the Edwards Plateau by 1700,
also convinced some Tonkawa to filter into the just-established Spanish communities. No match
for these invaders’ military prowess, and seeking protection the Spanish seemed to provide,
Tonkawa and other displaced Indian peoples converted to Catholicism, a Spanish prelate
declared, “for fear of the Apache.” His insight suggests a broader transformation was underway:
“By the end of the 17th century,” argues archaeologist T.N. Campbell, “the Indians of southern
Texas were already beginning to face what most hunting and gathering peoples of the world have
had to face,” including “population decline, territorial displacement, segregation and ideological
pressure, loss of ethnic identity, and absorption by invading armies.”6
This fundamental alteration is most visible in the new work the Tonkawa took up under
the Spanish flag—their indispensable, back-backing efforts to dig an expanding network of
acequias (irrigation ditches). With crowbars, picks, and axes, they cut trenches that ran parallel to
the San Antonio River, from its headwaters downstream to the missions; this distribution system
made arable lands that never before had been cultivated, and provided water to a small, but nowpermanent population consisting of civilians, Indians, missionaries, and soldiers. By capturing
their converts’ energy, the Spanish had harnessed the river’s flow; their control over land and
labor freed them to introduce a new stage of human economy to the region, agriculture, and
ranching. With water, came power.
Growth would come, too. That is what Captain Domingo Ramon predicted in 1716, when
his expedition to eastern Texas briefly sojourned in the San Antonio Valley. Like others before
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and after him, he was struck by the area’s river-fed verdancy, the luxuriance of its surrounding
“nopals, poplars, elms, grapevines, black mulberry trees, laurels, strawberry vines, and genuine
fan palms.” This arboreal beauty also signified town-building potential. After examining the
first of the gushing springs he would encounter, Ramon concluded that there “was sufficient
water here for a city of one-quarter league,” an estimation he no doubt expanded when later he
traversed the nearby San Antonio River. What he meant by the site’s potential dimensions may
be unclear, but subsequent Spanish settlement, with its substantial investment in acequias to
enhance agricultural, commercial, and household consumption, was predicated on Ramon’s
insight into the essential connection between streamflow and urban development. Without ready
and consistent access to water, there could be no San Antonio de Bexar.7
Mexicans and Americans would reach the same conclusions. Indeed, neither of the two
successors to the former Spanish territory in south Texas were able immediately to alter the
degree to which water, its presence and absence, conditioned life in this frontier outpost. Each
new government—the Mexicans took over in the early 1820s, the Americans in the mid-1840s—
made full use of the acequias to distribute water; and each patterned its regulatory authority over
water on Spanish legal precedents. That they were able to exist within this older system was a
consequence of San Antonio’s distance from major population centers and markets; it grew very
slowly until after the Civil War, and was therefore able to absorb increases in demand.
Even when the delivery system was stressed, the community generally finessed dry spells
by a conservative use of water. Its need to adapt to this environmental pressure puzzled poet
Sidney Lanier, who spent the month of February 1873 in San Antonio, then a modest town of
12,000. Among the town’s peculiarities, he wrote, was that “it was built along the banks of two
limpid streams, yet it drinks rain-water collected in cisterns.” Had he remained in town during
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for the coming dry spell, he would have better understood why the citizenry was compelled to
harvest rainfall.8
A mere four years later, even rigorous conservation could not stave off a looming,
perilous depletion of potable water supplies. The locus of change was the 1877 arrival of the first
railroad, the Galveston, Harrisburg, & San Antonio. Its black smoke marked the end of the city’s
isolation from national and international marketplaces and spurred a boost in population. In
1880, more than 20,000 lived in the city, and, spurred on by a second rail link in the mid-1880s,
it would claim 40,000 within a decade. Once streetcar lines were laid down, new and old
residents were able to move across the urban landscape with greater facility, and housing
districts and commercial activity spread out, the acequia water-delivery system was overmatched.
This untenable situation was made worse by a lack of sewers, such that commercial
effluent was dumped into the ditches or slopped into the river or creeks. Most liquid household
wastes and human excreta were supposed to be captured in cesspools or underground privyvaults, but invariably the contents leeched into the soil and nearby wells. The resultant public
health problems were expected to get worse as the city swelled in size: “the primitive means of
...disposal answered while [San Antonio] was a village,” the head of the West Texas Medical
Association noted, but “such is inadequate to a population of 30,000, and cannot continue
without disastrous effects.” Not until the mid-1890s, after years of political debate, did a citywide sewage system go on line.9
The Cheap Water Age
However innovative, this welcome change in urban-sanitation disposal depended on an
even more radical alteration in water supply and delivery that transformed the historic
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relationship between the people and the land. Once compelled to live within oft-severe
environmental constraints, San Antonians of the 1890s entered into an era in which technology
seemed to promise a release from nature.
The key promoter of this brave new world was George W. Brackenridge. A shrewd and
contentious man, he was the city’s major banker, published the Daily Express, and was lead
shareholder of the privately owned Water Works Company. It did not hurt that he owned
hundreds of acres surrounding the springs from which rushed the San Antonio River, and it was
from this property that his company captured and distributed its flow. By 1885, Brackenridge
had invested in pumps to suck up water and push it through what grew to be 100 miles of
pipeline serving residential and commercial customers; the resourceful entrepreneur even rented
a network of fire hydrants to the city, for $25,000 a year. His dominance of public works and the
civic economy was controversial, leading rival newspapers to denounce Brackenridge as “The
Monopolist”; local politicians--especially in election seasons--lambasted his imperial grip.
The community only had itself to blame. Its legendary aversion to levying taxes to pay
for infrastructure, frequent defaulting on bank loans, and curious refusal to pay its bills meant
that private investment and investors were essential to the creation of city services. Even when
Brackenridge offered to sell the water works to the city at bargain prices, the political leadership
rejected the deals. They may have feared and despised him, but they also depended on his
financial acumen and deep pockets.
Brackenridge drew again on those ample resources in the early 1890s, when, urged on by
a local medical official who was convinced that artesian wells would provide pure water and
inoculate the citizenry from cholera and other infectious diseases, Brackenridge began to drill
test wells near ojo de aqua, the source of the San Antonio River; a three-thousand foot well came
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up empty. But in 1893, he struck pay dirt downtown: “The fresh water supply of San Antonio is
apparently unlimited," the Daily Express reported. "It has been increased three million gallons
for each twenty-four hours by a splendid strike...on the property of Colonel George Brackenridge
on Market Street.” Additional wells dug into the artesian zone of the Edwards Aquifer, and the
purchase of steam-driven pumps to flush water along what one historian has called the
“mushrooming tendrils” of the Water Works Company pipelines, insured the year-round
availability of clean and cheap water to a city long accustomed to episodic drought.10
Readily tapped and distributed, the new water supplies nourished the rapid population
growth that defined its twentieth-century history, and its corresponding economic expansion. By
1925, when the city finally scraped up seven million dollars to buy the private water works, and
renamed it the City Water Board, San Antonio boasted nearly 200,000 inhabitants, making it the
largest city in Texas.
This boisterous pattern of growth came with a series of environmental costs and social
concerns. Accelerated pumping in time would lower the level of the Edwards Aquifer,
diminishing the natural flow from the community’s many springs, reducing the volume of the
San Antonio River and San Pedro Creek, and elevating anxieties about the long-term stability of
local water supplies. Although water was cheap, and had become publicly owned, it was not, and
would not be until the 1970s, equitably distributed; the city’s poor rarely had indoor plumbing
and often had to trek blocks to locate outdoor faucets. Explosive population increases in the postWorld War Two era, combined with a crippling drought in the 1950s, intensified these
inequities, and reminded the city just how powerful nature could be in shaping the contours of
life in south Texas.11
But cracks in foundations, buckled water mains, and the occasionally empty spigot did
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not halt the city’s automobile-driven, northerly sprawl of housing subdivisions, shopping malls,
and commercial nodes. By the 1970s, some developments even threatened to seal over the
aquifer’s recharge zones. This fraught situation was doubly alarming, for the Edwards Aquifer
remained the sole source of potable water. It did not help matters, political scientist Heywood
Sanders has observed, that penny-pinching politicians and a frugal water board of the 1950s, “so
long committed to low rates and limited capital spending," had hobbled the city's search for more
water. That pattern held true until the 1990s, such that the community’s unending struggle over
issues of water quality and quantity was (and is) best depicted each summer in the ominous
newspaper graphs that illustrate daily fluctuations in the aquifer’s level. San Antonio’s diet of
cheap water turned out to be an expensive, nerve-racking habit.12
Future Course
Since the 1970s, protesters have challenged the city council’s relentless pursuit of growth
for its own sake; giving pause as well has been federal enforcement of the Endangered Species
Act to protect flora and fauna living within the aquifer's subterranean waters and its aboveground springs. By the 1990s, it seemed clear that the era of unrestrained pumping was coming
to an end, just as the city experienced yet another surge in population, yet another damaging dry
spell, yet another set of over-heated summer temperatures. The result was a long-overdue
reassessment of the city’s water policies, the central goal of which became the hunt for new
sources of water to decrease reliance on the aquifer.
The proposed first step was to build the Applewhite Reservoir in southern Bexar County,
which would impound the languid flow of the Medina River. Originally discussed in the early
1950s, and shelved when engineering studies suggested the site’s geologic inadequacies, the idea
was revived in the early 1990s. Protestors forced the reservoir issue on to the ballot in 1991
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through a successful petition drive, and they rallied enough opposition to defeat the surfacewater project at the polls; three years later, they beat back even more decisively a second
Applewhite initiative. For this second round, anti-Applewhite forces rallied under the banner
“No Means No!” and successfully raised doubts about the reservoir’s projected costs,
environmental impacts, and hydrological integrity.
The city’s hunt for water subsequently shifted away from plans that might face electoral
scrutiny, and to a strategy that would finesse the political process yet develop mechanisms to
slake the city’s unquenchable thirst. Steep increases in water bills, for instance, would enable the
city to generate sufficient revenue to fund initiatives to conserve present-day resources and tap
additional supplies. The driving force behind what has emerged as the city’s latest phase in water
politics has been the San Antonio Water System (SAWS). Born of the old City Water Board, by
way of Brackenridge’s original Water Works Company, SAWS in late September 2000 halted
the cheap-water age its organizational progenitors had launched and sustained since the late
nineteenth century. The agency’s board agreed to levy a monthly water-supply fee that would
boost bills by nearly 21% (with additional hikes expected); it also set “a conservation-oriented
pricing structure for the utility’s general class [of consumers]—apartments, businesses and
industry,” equalized water rates among the different classes of users, and established a billassistance program to insure that low-income households would not be adversely affected by
rising costs. As critics were quick to point out, the proposed structure actually lowered per-unit
prices for large commercial users, but overall the new approach was to net SAWS an additional
$20 million in its first year, and ever more thereafter. “While we have not come to the perfect
conclusion,” then-Mayor Howard Peak admitted, “the balance is pretty good and is a significant
next step for us in the process of refining our rates and providing money necessary to buy new
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water for San Antonio.”13
Actually, the initial move was to squeeze new water out of old. SAWS, beginning in the
late 1990s, rolled out an innovative water-recycling program. Treated, non-potable wastewater is
now piped throughout San Antonio for large-ground landscaping, including golf courses, office
parks, and commercial and educational sites. By late 2001, SAWS declared that it was recycling
approximately 11 billion gallons a year. This news dovetailed with a massive push to educate
consumers about the need to be conservation-minded, which entailed financial incentives to shift
to more water-efficient plumbing. The impact has been striking: since the mid-1980s, water use
has dropped 32%, with a 45% decline predicted for 2015. San Antonio’s per capita consumption,
once among the highest in the state, is now its lowest. Conservation had proved its worth,
observed SAWS board president James Mayor, “because [it] is the cheapest source of new water
available to us.”14
That did not stop SAWS from pursuing more costly supplies. Like other public and
private purveyors throughout the southwest, it aggressively entered water markets, using its
capital to sop up unused rights in Bexar and its surrounding counties. It also successfully
negotiated with an ALCOA lignite mine in Bastrop County, northeast of Austin, for 90,000 acrefeet of water in the Simsboro Aquifer, a basin transfer that received the legislature’s blessing but
which in October 2005 SAWS decided not to pursue. South of San Antonio, SAWS began to
purchase tracts of land over the sandy Carrizo-Wilcox aquifer; it intends to store excess Edwards
flow in what amounts to a modern-day, underground cistern. The total tab for the project, which
includes a new water-treatment plant, wells, and pipeline infrastructure, will top $215 million, a
huge investment and second only to that paid out for a similar facility by cash-rich, but very arid
Las Vegas, Nevada. For a community that had so rarely invested in its future, San Antonio
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seemed to have undergone a personality change with the ringing in of the new millennium.15
Not everything was transformed: local water fights did not cease, they simply shifted in
venue. As individual farmers and ranchers reaped a profit by selling portions of their water rights
to SAWS, their rural communities worried about the decline in traditional agrarian values; the
reach across watersheds to divert water to San Antonio has provoked protests from distant
counties against what they perceive as the city's water imperialism. Closer to home, the decrease
in the San Antonio's dependence on the aquifer has generated some worry that the new-found
independence perversely will accelerate construction over the Edwards; why protect it, if its
waters are no longer so essential? Embedded in these and other plaintive appeals is a core
concern: south Texas, like the rest of the American southwest, has not yet devised a common
language by which to discuss water, either to define past uses, articulate contemporary needs, or
plot future demand. Perhaps it is impossible to think about water as a commons, and to act
accordingly, but as San Antonians have discovered, the lack of such binding language and
unifying vision has impeded the resolution of a tangle of economic, environmental, and social
needs. Making this case abundantly clear has been the divisive debate that erupted over plans to
lay down the PGA Village complex over one of the most sensitive portions of the Edwards
Aquifer recharge zone.
Acknowledgement: This is a revised and updated version of an article that originally
appeared in the Journal of the West, Summer 2005, p. 44-50.
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Notes
1. San Antonio Express-News, February 3, 2001, p. 1A.
2. San Antonio Express-News, February 11, 2001, p. 4G.
3. In subsequent months, the city and the developers reworked their agreement, broadening
support for the proposed development on the council; public opposition reignited in December
2002 when the city determined that its new proposal need not be brought before the voters, a
decision that was upheld in Federal court. When the city then let the agreement lapse, so that it
would not face a public referendum, it then launched a new effort: in late 2004, the city wooed “a
new partner, PGA Tour, and…set up a 29-year non-annexation agreement with tighter
environmental controls and wage guarantees. Proponents said the new design is superior to much
of the development going on around the site, as well as to the dense housing that Lumbermen's
could have built there.” By the summer of 2006, much of the financing was in place, and
construction had begun on the golf resort and residential complex. San Antonio Express-News,
October 6, 2002, p. 1B; December 11, 2002, p. 12A; December 5, 2005, p. 1B; December 10,
2005, p. 3B.
4. Karen E. Stothert, “The Archaeology and Early History of the Head of the San Antonio
River,” (San Antonio: Southern Texas Archaeological Association Special Publication Number
Five, and Incarnate Word College Archaeological Series Number Three, 1989), p. 1-39; W. W.
Newcombe, The Indians of Texas: From Prehistoric to Modern Times, (Austin: University of
Texas Press, 1960), p. 131-140.
5. Shelly C. Dudley, “Water, the Gila River Pimas, and the Arrival of the Spanish,” in Char
Miller, ed., Fluid Arguments: Five Centuries of Western Water Conflicts (Tucson: University of
Arizona Press, 2001), p. 27-39.
6. T. N. Campbell, “The Payaya Indians of Southern Texas,” (San Antonio: Southern Texas
Archaeological Association Special Publication, No. 1, 1975), p. 1-2.
7. Stothert, “The Archaeology and Early History of the Head of the San Antonio River,” p.
1-5.
8. Sidney Lanier, "San Antonio de Bexar," in Philip Graham, ed., Sidney Lanier: Florida
and Miscellaneous Prose, (Baltimore; The Johns Hopkins University Press, 1945), p. 202.
9. San Antonio Express, July 7, 1883; August 1, 1883.
10. Bobbie Whitten Morgan, “George W. Brackenridge and his Control of San Antonio’s
Water Supply, 1869-1905,” Master’s Thesis, Trinity University, San Antonio, 1961, p. 98.
11. Donald Everett, San Antonio: The Flavor of its Past, 1845-1898, (San Antonio: Trinity
University Press, 1976), p. 55-56; 59; George Waring, Jr., compiler, Report of the Social
Statistics of Cities, (Washington, D.C.: Government Printing Office, 1887), p. 332.
12. Heywood Sanders, “Empty Taps, Missing Pipes,” in Char Miller, ed., On the Border: An
Environmental History of San Antonio, (Pittsburgh: University of Pittsburgh Press, 2001), p.
167.
13. San Antonio Express-News, September 27, 2000, p. 1A.
14. John Mayor, “Conservation helped buoy water supply,” San Antonio Express-News,
October 3, 2001.
15. Ibid., October 27, 2005, p. 3B; June 20, 2006, p. 1B.
Copyright © 2006 by Char Miller.
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Protecting Our Water and Natural Heritage
Eric Lautzenheiser
Nature Preserve Coordinator
San Antonio Parks and Recreation Department
Friedrich Park
21395 Milsa
San Antonio TX 78256
(210) 698-1057
[email protected]
Bexar County is one of three counties in Texas with the highest number of endemic plant
species. Most of these endemics grow in the area of the Balcones Escarpment, where the most
rapid urban growth is also occurring. On May 6, 2000, San Antonio voters approved a temporary
1/8-cent sales tax to generate $45 million to protect the quantity and quality of water entering the
Edwards Aquifer. Property to be preserved under this program includes the recharge and
contributing zones for the Edwards Aquifer--essentially the Balcones Escarpment. The program
was completed in 2004 with over 7,000 acres protected. In 2005, San Antonio voters approved a
continuation of the taxation to generate an additional $95 million for Edwards Aquifer
protection. The results of this project are impressive and represent the most serious effort yet to
preserve the region’s primary source of water. The program also represents a significant
protection of the area’s natural heritage. This presentation will examine the means used to
acquire property, with emphasis on the creation of a GIS model to target acquisitions, and an
overview of the properties and their plant and animal communities preserved to date.
Bexar County is one of three counties in Texas with the highest number of endemic plant
species. Most of these endemics exist in the area of the Balcones Escarpment, where the most
rapid urban growth is occurring.
On May 6, 2000, San Antonio voters approved a temporary 1/8th cent sales tax to
generate $45 million to protect the quantity and quality of water entering the Edwards Aquifer.
Property to be preserved under this program is the recharge and contributing zones for the
Edwards Aquifer – essentially the Balcones Escarpment. The program was completed in 2004
with over 7,000 acres protected. In 2005, San Antonio voters approved a continuation of the
taxation to generate an additional $95 million for Edwards Aquifer protection. The results of this
project are impressive and represent the most serious effort yet to preserve the regions primary
source of water. The program also represents a significant protection of the area’s natural
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heritage.
Of the original $45 million, $38.4 million were allocated to land purchase; $1 million for
appropriate development to allow public use; $1.1 million for financing the program ahead of
schedule due to land prices escalating at 80% and more per year; and $4.5 million placed in
escrow for maintenance and operations of acquired land.
Immediately following voter approval, two advisory boards and an acquisition team were
created to guide the project and assist in implementation. The Scientific Evaluation Team (SET)
was composed of scientists and technicians in fields of the natural sciences and computer
modeling. SET was charged with creating a computer spatial model that would identify and
prioritize all lands in the Edwards Aquifers’ sensitive areas that might be purchased under the
program. The model created by SET evaluated all lands within the target area on a one square
meter grid. Multiple layers of data were grouped into three value classes, and each square meter
of land received an overall value based on these three classes, with geology (recharge potential
and sensitivity) given a weight of 50%, watershed (protecting larger portions of distinct drainage
systems) given a weight of 30%, and biological (ecosystem health and potential presence of
endangered species) given the remaining 20%.
The second board was named the Conservation Advisory Board (CAB). Their
membership was composed of community stakeholders concerned with water issues. They
included representatives from Texas Parks and Wildlife, Edwards Aquifer Authority, San
Antonio Water System, San Antonio River Authority, City of San Antonio Departments of Parks
and Recreation and Public Works, Open Space Advisory Board, Parks and Recreation Advisory
Board and a member of the business community.
The acquisition team was composed of three not-for-profit land conservation
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organizations (Bexar Land Trust, Texas Nature Conservancy and Trust for Public Land), the
city’s Project Manager, and San Antonio River Authority staff. This team helped target the
computer-modeled, prioritized land parcels, inspected the parcels, performed due diligence
evaluations, and negotiated with owners. At each step of the process, this team’s information
was provided to the CAB, which in turn evaluated the input to provide further directives to the
acquisition team.
The geographic scope of potential protection was legally limited to within Bexar County
and the City of San Antonio’s extra-territorial jurisdiction. Land could be protected in three
manners: fee simple purchase, donation, or perpetual conservation easements.
Fourteen properties totaling over 6,500 acres have been protected. Most were purchased fee
simple, one property was protected under conservation easement, and several partial donations
occurred. With property values escalating by triple digits, this is a truly remarkable
achievement.
Effort was extended to purchase properties in clusters with the idea of an eastern, central
and western preserve. An Eastern Preserve was attempted, but conditions of development and
land prices precluded this goal from becoming a reality. Properties acquired were successfully
clustered into two blocks, or preserves. The Central Preserve is around Friedrich Wilderness
Park, from just west of IH-10 to near the city of Grey Forest. The Western Preserve is made up
of properties around Government Canyon State Natural Area. Each individual property (or unit)
protects the aquifer recharge zone proper and/or the immediate contributing zone supplying
water to the recharge zone. The properties possess distinct characters representing different
aspects of the Balcones escarpment of the Texas Hill Country and are rich in a diversity of native
flora and fauna, including many endangered and threatened species.
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The Central Preserve has five units totaling just over 2,075 acres. All units are currently
identified by the name of their previous owner or the development project from which they were
acquired.
The 327-acre Woodland Hills unit was acquired December 30, 2003, and included a 40acre donation. This property was accepted by city the council as an addition to the existing 260acre Friedrich Wilderness Park. This unit extends the FWP boundaries to the north; to the south
to Heuermann Road, across from the Crownridge Canyon unit; and to the west across Babcock
Road to the Cedar Creek unit. The property had been under development as a golf resort and
some scarring of the land occurred prior to purchase; however, the property contains
considerable golden-cheeked warbler habitat and some high potential black-capped vireo
habitat. This unit greatly expands and protects the original FWP property, which is breeding
habitat for both bird species. Three plant species rarely seen in Bexar County are preserved in
this unit: Arisaema dracontium (green dragon), Onosmodium helleri (marbleseed) and Amsonia
ciliata (blue-star). Many other endemic and unusual plants are found on this tract as is true of all
the tracts. The view sheds from existing hiking trails are significantly more protected to the
north and west. Protection of two of three watersheds within the park is also greatly increased.
Just south of Heuermann Road, adjacent to the above unit, is the 211-acre Crownridge
Canyon unit, acquired April 2, 2001, with a $105,000 funding augmentation from a council
district eight 1999 park bond. The bulk of this unit fronts on Luskey Boulevard, near the
intersection of Camp Bullis Road and Babcock Road. It is a smaller, but exquisitely beautiful
unit located on the contributing zone, just upgrade of the recharge zone. This unit was soon
targeted as the “flagship” of the project to construct improvements to allow public use.
Biological and geological investigations were performed to guide appropriate development, use
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and management. golden-cheeked warbler habitat was identified and proven to be occupied.
black-capped vireo habitat was marginal at best, but the potential remains for one or two
breeding pair. Geological investigations identified numerous recharge features, and further
investigations identified federally-listed endangered karst invertebrates in one feature. One of
the cave beetles, Rhadine infernalis infernalis was positively identified. More intriguing was the
potential identification of a listed cave spider, Cicurina madla. The curious elements limiting
positive identification of the spider are the specimen collected was male and immature. Only
females of the species have ever been positively identified and described. So our troglodytic
spider was reared and spent the remainder of his life span in a laboratory. He has contributed his
body to science and awaits DNA analysis to confirm or deny his true identity. It is possible that
Crownridge Canyon Natural Area will yield the first known scientific identification of a male
Cicurina madla. Several colonies of Macrosiphonia macrosiphon (flor de San Juan) are found on
this property and not known from any of the others. Crownridge Canyon Natural Area was
opened to the public in spring of 2006.
Further west and connected to the Woodland Hills unit is the Cedar Creek unit. These
242 acres were acquired May 4, 2001. This unit has an eastern terminus at the intersection of
Babcock Road and Kyle Seale Parkway, and then expands westward and southward to surround
the Cedar Creek municipal golf course. The land is mostly steep, easterly facing gradients with
high potential for golden-cheeked warbler habitat. The unit spans the contributing zone and
recharge zone. This unit also protects a part of the Babcock Creek watershed, and connects the
previously mentioned units to the east with the large Thrift unit to the west.
The Thrift unit was acquired in three separate transactions. On March 26, 2001, a 640acre portion was acquired. On March 11, 2002, the owners agreed to transfer an additional 434
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acres, including a 31.3-acre donation. And finally, the last 78.4 acres was acquired by donation.
Within the Grey Forest ETJ, the project was not allowed to expend funds toward acquisition of
this last unit. The Edwards Underground Water Authority and the San Antonio Water System
worked together to acquire the property and on November 4, 2002, title ownership of the unit
was transferred to the city. The composite unit of just under 1,153 acres is truly the anchor for
the Central Preserve. It is large, it encompasses a large watershed, it spans contributing and
recharge zones, seems to have some habitat occupied by golden-cheeked warblers, but is the
mother lode of black-capped vireos, and has high potential for listed karst invertebrates. A
cursory inspection identified 32 singing male black-capped vireos, which exceeds the previously
known population of this bird in Bexar, Comal, Kendall, and Medina counties combined!
Muhlenbergia dubia (pine muhly) and Calliandra conferta (fairy-dusters) are common on this
property. Ceanothus herbaceous (redroot), an attractive shrub not often seen in our area, is
found on this property. Sharing an eastern boundary with the Cedar Creek unit, the Thrift unit
expands west to Grey Forest. The unit has an unusually interesting historical use and extensive
structures dating back to the early 1900’s. These structures and improvements center around
Huesta springs, which still flow today, though their waters soon disappear into recharge features.
Just back to the east, north of 1604 and west of Babcock Road is the separate 145-acre
Medallion unit, acquired November 4, 2002, and included a 14.85-acre donation. This unit is
entirely on the recharge zone, contains one large, gated recharge feature, and the certainty of
many more features either expressed at the surface or not. The unit is also adjacent to a previous
karst preserve. This unit is relatively small. It likely contains no habitat for the black-capped
vireo or the golden-cheeked warbler. Only future investigations will determine presence or
absence of listed karst species. It is surrounded to a large extent by existing neighborhoods and
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perhaps has experienced more disturbance than any other acquisition. Yet it remains a good
example of Balcones Escarpment/Hill Country landscape with a good diversity of native flora
and fauna. It has significant value to the primary purpose of the project and potential to serve as
a fine mini-preserve for public enjoyment.
The Western Preserve comprises nine units totaling 5,018 acres. These units are
clustered around Government Canyon State Natural Area (GCSNA).
The 595-acre Iron Horse Canyon unit was purchased April 4, 2001. It is adjacent to the
northeast boundary of GCSNA and just west of Helotes. This rugged tract has Golden-cheeked
Warbler habitat and several known large karst features. The terrain is steep and rugged and
located on the recharge zone. This and other units in the Western Preserve add to or buffer
GCSNA from adjacent development and negative impacts.
The 1,164-acre Kallison Ranch unit became the southwest portion of GCSNA. The
project provided half the funds necessary to protect this property in return for a perpetual
conservation easement. The state, through a federal Land and Water Conservation Fund grant,
provided the other half of the funds and received title and management responsibilities for the
land as an addition to GCSNA. The unit lies mostly on the recharge zone with a small portion
extending southward onto the artesian zone. A few older ranching structures are on the property,
one of which may serve to house GCSNA interns or visiting researchers. That portion of the
property could also be developed for interpretation of ranching and other historical land uses. In
completing acquisition of this property, the state and city signed a joint agreement signifying a
partnership relative to their respective adjoining lands, including master planning, programming
and general management.
Immediately to the west, adjoining both Kallison and GCSNA is the 1,033-acre Windgate
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Ranch unit. The property was acquired on December 28, 2000, with an included donation of just
over 9 acres. Another unit with steep, rugged terrain, Windgate Ranch has spectacular views to
the south. On exceptionally clear days one can see the cooling towers at Calaveras Lake on the
opposite corner of the county. Preliminary investigations show some Golden-cheeked Warbler
habitat and expansive pre-historic quarry sites where Native Americans obtained stone for tools.
Forestiera reticulata (netleaf forestiera) and Jatropha dioica (leather stem) approach their
eastern-most distribution on this site. This unit is entirely on the recharge zone.
The 91-acre Schuchart unit ties on to the Windgate Ranch unit. It was acquired April 22,
2003. This transaction included a donation of almost 7 acres. Located on the recharge zone, the
Schuchart unit is part of the San Geronimo Creek watershed. Pavonia lasiopetala (rose pavonia)
is on this site. We have seen it on only one other site in Bexar County. Bernardia myricaefolia
(oreja de raton) is abundant on this site. It is a common shrub of the area, but not in other
preserved sites of Bexar County.
The 55-acre Laredo-Culebra tract was donated by City Public Service and immediately
adjoins Schuchart and Windgate on the south.
Three more tracts are located on the west side of Hwy. 211, across the road from the
Windgate unit and GCSNA. Acquired on April 17, 2002, the 345-acre Mayberry unit included a
donation from Texas Nature Conservancy of 176 acres located in Medina County and therefore
unavailable for purchase with program funds. The Mayberry unit is quite distinct from other
units with a segment of San Geronimo Creek running through the property. The high cliffs on
the eastern side of the creek and other portions of the valley have high potential for
archaeological significance. Some golden-cheeked warbler habitat is evident on this unit. The
entire unit is on the recharge zone. San Geronimo Creek is a near perpetual stream north of the
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unit, but quickly disappears into recharge features in the vicinity of this property except when the
creek is at higher than normal flow.
The 50-acre Hampton unit was added to the Mayberry unit on November 25, 2002. Also
located entirely on the recharge zone, this unit expands the Mayberry unit preserve and provides
improved access.
The 710-acre Chris Hill unit was acquired October 23, 2003. This unit is also entirely on
the recharge zone and part of the San Geronimo Creek watershed. It is mostly gently rolling
uplands, a landscape not well represented on other units. A windmill and other ranching
structures are on the property.
A final purchase of the 421-acre Mabe Tract in 2005 finished the original project.
Additional federal grant funds and interagency agreements were used to leverage the
effectiveness of the projects remaining funds. This unit closes an inset in the northern portion of
Government Canyon State Natural Area and is contiguous with the entire western boundary of
Iron Horse.
With approval of the 2000 tax initiative to preserve Edwards Aquifer sensitive lands,
voters charged the city with a daunting task. The city, its agents and volunteers have met that
challenge and produced outstanding results. Recognizing the success of this program and the
continuing importance of protecting the Edwards Aquifer, San Antonio voters have extended the
program for an additional $95 million. Work is currently under way to identify properties in
Bexar, Medina and Uvalde counties. State legislation has removed the restrictions to remain
within Bexar County or the San Antonio Extra Territorial Jurisdiction that were imposed on the
original program. Although the primary focus of this project was to preserve high quantities and
quality of water entering the aquifer, by applying a small weight to biological considerations the
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city was able to further select those properties with high biological value as well. What has
resulted is not only a significant effort to protect our primary source of water, but also a de facto
preservation of outstanding representations of our natural heritage.
In 2003 the city council adopted the “Land Use and Management Planning Guidelines for
Natural Areas” as an addition to the San Antonio Parks and Recreation System Plan. The
guidelines essentially mandate an initial comprehensive gathering of information related to
biological, geological, and cultural resources for each property. These data will then be modeled
in a manner similar to the SET model used for targeting acquisitions. The guidelines model will
assist in determining potential appropriate public use, locations for improvements needed to
allow appropriate public use, and in preparation of land management plans for each property.
Other than Crownridge Canyon Natural Area, no openings of other units are anticipated in the
near future. Much work must be accomplished to meet the requirements of the guidelines and
future sources of funds must be identified for any improvements. While the wait may be a bit
discouraging, public access must wait upon the completion of necessary studies, planning and
funding of improvements required to allow appropriate use. The primary program purpose was
to protect our water; and this has been accomplished. In meeting the primary purpose we have
also preserved the land and its natural systems for ourselves and future generations.
Copyright © 2006 by Eric Lautzenheiser
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Sabal Mexicana Palm Trees, Native to San Antonio. And Beyond?
Landon Lockett
3210 Stevenson Avenue
Austin, Texas 78703
(512) 476-195
[email protected]
For decades botanists believed that Sabal mexicana (syn. Sabal texana), Texas’ only
normally tree-sized native palm species, was not native north of the Lower Rio Grande Valley.
In 1989, however, a wild population of S. mexicana was discovered along Garcitas Creek, the
border between Victoria and Jackson counties, and 200 miles north of the lower Rio Grande
(Lockett and Read 1990). Further, reports from as far back as the LaSalle colony, founded in
1685 (Margry 1876-1886), and from such notable nineteenth-century botanists as Ferdinand
Lindheimer and George Engelmann, mention palm trees with, as Lindheimer noted, trunks of 20
to 40 feet tall along rivers draining into the central coast (Lockett and Read 1990, Lockett 1995).
While Lindheimer and Engelmann did indicate the downstream limit of the occurrence of
palm trees—since Sabal mexicana is not salt-water tolerant it would have been the downstream
limit of fresh water—they said nothing as to how far inland from the coast they occurred. There
is, however, one piece of historical evidence indicating that the species occurred at least as far
inland as San Antonio.
In 1716 Fray Isidro Felix de Espinosa, a Mexican priest accompanying the Spanish
expedition of Domingo Ramón on its way to northeast Texas, listed in his diary plants he saw
growing at San Antonio Springs, now Brackenridge Park, in San Antonio (Espinosa 1716). His
list includes “nogales altísimos, álamos, olmos, parras, morales, madroños, y palmitos
legítimos.” (See attached copy of diary entry for May 14, 1716, containing his description of San
Antonio Springs.) The first six of these plants are readily identified as very tall pecan trees,
cottonwoods, elms, grapevines, mulberry trees and madrones. But what did Espinosa see that he
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called palmitos legítimos?
At first glance the answer seems obvious. What could palmitos mean other than dwarf
palmettos (Sabal minor)? One problem with this interpretation is that to the extent I wandered
around in Brackenridge Park, I saw no S. minor, only planted Washingtonia, and planted or
escaped (or natural?) Sabal mexicana. And therein lies a source of possible confusion.
While I saw no dwarf palmetto, I saw many young (trunkless) S. mexicana.
Unsurprisingly, to most people’s eyes, young (trunkless) S. mexicana is identical to S. minor.
Often I’ve had people who are sophisticated about plants tell me they have seen a S. minor
growing in such and such a place. I tell them to look at the palm again and see whether it has a
tangle of threads in the leaves. (See attached photograph of young S. mexicana in Inks Lake
State Park.) When they report that there is such a tangle (S. minor has only s few threads), I tell
them that the plant is S. mexicana, not S. minor. Owing, perhaps, to the longstanding and deeply
rooted assumption that S. mexicana is a “tropical” tree, barely managing to cling to life along the
southernmost loop of the Rio Grande, people north of the Valley find it hard to imagine that that
palm in their backyard is Texas’ own Sabal mexicana. Instead they assume it is S. minor, if
trunkless, or an exotic if it has a trunk. If you visit, for example, the Zilker Park Garden Center in
Austin, you will see young S. mexicana that are mistakenly labeled S. minor. As for S. mexicana
in Brackenridge Park, there are trunked specimens planted along the roads, but also others
scattered here and there that appear not to have been planted, although they are likely to be
progeny of the planted specimens. On the other hand, in Olmos Park, just upstream from
Brackenridge, aside from the scattering of young S. mexicana there is a small grove of trunked S.
mexicana hidden in the woods along the Audubon Society nature trail.
What, then, did Espinosa see that he called palmitos legítimos? If we take Espinosa at his
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word, and grant, from his description of the site, that he had some sophistication about plants, the
answer is easy. In an article in the journal Cactáceas y Suculentas Mexicanas, titled “El
Palmito,” and about Sabal mexicana, Mexican botanist Ignacio Piña Lujan states plainly that S.
mexicana, which has a widespread distribution in Mexico, is known there by the common name
of palmito (Piña Lujan 1972, page 84).
But why would a tree that can reach 50 feet tall be called by the diminutive term palmito?
The answer goes back to Spain, where there is a small native palm called palmito, which has an
edible heart also called palmito. Therefore when the Spanish came to the Americas they called
any palm they found, no matter how tall, that had an edible heart, palmito. Florida also has a
palm tree, called in English the cabbage palmetto, that has an edible heart. The Spanish called it
palmito, and this word is preserved in its scientific name, Sabal palmetto, which, in spite of the
use of a diminutive as its epithet, can grow to 90 feet tall.
If Sabal mexicana is native as far north as San Antonio (or farther north?), what became
of them? Their virtual disappearance springs from their many uses. We already know they have
an edible heart. Imagine what probably happened when hungry Spanish explorers came upon a
grove of palmitos. To get the heart you have to cut down the tree. Further, because of its
durability, palm wood was used for fence posts. What pioneer would reject such a convenience
as ready-made and extra-durable fence posts? The main threat, however, was commercial. Most
wood, when immersed in water, is attacked by a kind of clam called the shipworm (Teredo
navalis). Palm trunks, however, are resistant to the shipworm and were accordingly in enormous
demand for use as pilings for wharves. An 1872 U.S. Army Corps of Engineers report calls for
10,000 palm trunks in its specifications of materials needed for constructing jetties at the mouth
of the Brazos River (Howell 1872).
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On top of that, S. mexicana, Texas’ only native palm-tree species, was in great demand
for use in landscaping, and the effects of this can be seen today. Prowl the older neighborhoods
and near older buildings in cities and towns of the southern half of Texas and you’ll see big, old
S. mexicana standing on lawns, with its progeny coming up here and there. (See attached picture
of 44-foot-tall S. mexicana growing in front of a schoolhouse in Georgetown.)
Finally, for those who consider the 300-year-old scribblings of a wandering priest to be
hardly sufficient to overturn the wisdom that tells us that if they are palm trees they certainly
could not be native anywhere north of the sun-drenched Rio Grande Valley, we have the opinion
of Bill Carr, a botanist with The Nature Conservancy. Carr finds S. mexicana in San Antonio
escaping cultivation so profusely that he believes it is native there (Carr, personal
communication). We think of palms as tropical, even though many palm species are not. We
unconsciously assume they are exotics and just don’t belong. Lenadams Dorris, a writer and
palm grower in Nevada, writes of “[t]he refusal of most North Americans to conceive of palm
trees as belonging anywhere they themselves are living….”
Regardless of what we native-plant enthusiasts may think of palm trees, Sabal mexicana
is here, and it is native. The only question is, How far north did its range extend before it was
virtually extirpated by wharf builders and landscapers? The fact that, when planted even
hundreds of miles north of the Lower Rio Grande Valley, this palm thrives and reproduces does
not tell us much. What does count in determining whether the species is native to a particular
local is whether it is growing in a wild environment, even if the population in question is clearly
a case of escape from cultivation. When I give a talk like this one, I normally tell the members of
the audience that if they see a palm tree in the woods I want to know about it and I give them the
means to notify me.
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This request has produced some surprising results. In one case I was called to the little
Central Texas town of Praha where I found, to my great surprise, a vigorous wild population not
of the expected Sabal mexicana, but of the Sabal palmetto, the common sabal palm tree of
Florida. In another case, near Austin, the palm trees growing in the wild turned out to be
Trachycarpus fortunei, a Chinese palm commonly grown as an ornamental, but which I’d never
seen escape into the wild.
But the method has also paid off. Dorothy Mattiza took me to a site west of Medina.
Started by three S. mexicana that were planted near a ranch house in about 1900, there is now a
large population, with seven reproducing palms, spreading over two ranches. (See photograph.)
Another friend has taken me to a site in the woods of Inks Lake State Park. Here several young
S. Mexicana circle a den tree about 50 feet from the lake. Since there was no parent palm in
sight, we figure that fruit from some planted palm upstream had fallen in the lake, and then
washed up on shore, where raccoons had found it and taken it to their den tree, then eaten the
fruit and dropped the seeds. Otherwise, with escaping palms far from their parent, the young
palms would be widely scattered, not just in a small circle. (See photograph of young S.
mexicana.)
Populations such as those described above, hundreds of miles north of the Rio Grande
Valley, show us some places where S. Mexicana could have been native. Perhaps they are on the
northern periphery of the original range of the species, although I have too many times been
surprised by palms appearing where they were not supposed to be to jump to conclusions. I also
must assume that the populations near Medina and at Inks Lake State Park are all cases of escape
from cultivation—unless there is historical evidence that the species has always been at these
sites. Besides, historical evidence is hard to come by. With exceptions such as Espinosa,
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explorers and early settlers would not necessarily have noted the presence of palm trees. Even on
Garcitas Creek today, where we have the only known natural population north of the Rio Grande
Valley, ranchers take the S. mexicana on their land for granted. Further, historical palm-research,
aside from typically involving a needle-in-the-haystack search in old, handwritten documents for
offhand references to palm trees, is plagued by the ambiguity of two critical words—“palmetto”
and “palm.” Both words can refer to either S. mexicana or S. minor.
William McClintock visited San Marcos (Aquarena) Springs in 1846 and wrote in his diary, “In
the eddies of the stream water cresses and palmettos grow to a gigantic size.” But what species
were these “palmettos?” Sabal minor or Sabal mexicana? There’s no doubt that there are S.
mexicana palms there today, and they are reproducing abundantly. But were they there in 1846?
McClintock’s description of the springs appears in the July 1930 issue of Southwestern
Historical Quarterly (Vol. 34, No. 1, page 33).
In the 1840s, a German settler in New Braunfels wrote to his relatives back in Germany
that for Christmas they decorated their house with palm leaves. S. minor or S. mexicana? There
is a chain of notable springs from San Antonio to New Braunfels to San Marcos to Barton
Springs in Austin. They could have all had their respective populations of palm trees, but,
considering their locations, they would have been the first to go.
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Literature Cited
Espinosa. 1716. Diary of Fray Isidro Felix de Espinosa. Latin American Collection of University
of Texas Library, Austin, Texas.
Howell, C.W. 1872. Letter dated March 12, 1872, from Howell to G.A. Grow. Annual Report for
the Chief of Engineers for 1875, Appendix S8, pp. 939-941.
Lockett, Landon and Robert W. Read “Extension of Native Range of Sabal mexicana (Palmae)
in Texas to Include Central Coast,” Sida, Vol. 14, No. 1 (June 1990), pages 79-85. This
extension is shown on the range map for Sabal mexicana on page 108, Vol. 22, of Flora
of North America.
Lockett, Landon “Native Texas Palms North of the Lower Rio Grande Valley: Recent
Discoveries,” Principes, Vol. 35, No. 2 (April 1991), pages 64-71. Cited on page 109,
Vol. 22, of Flora of North America.
Lockett, Landon “Historical Evidence of the Native Presence of Sabal mexicana (Palmae) North
of the Lower Rio Grande Valley,” Sida, Vol. 16, No. 4 (Dec. 1995), pages 711-719.
Margry, P., Ed. 1876-1886. Découvertes et Établissements des Français dans l’Ouest et dans le
Sud de l’Amérique Septentrionale (1614-1754). Maisonneuve, Paris, 6 vols.
Piña Lujan, Ignacio. “El Palmito.” Cactáceas y Suculentas Mexicanas 17:84-92.
Copyright © 2006 by Landon Lockett.
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Photographs
1
Entry in Espinosa’s diary for Thursday, 14 May, 1716. It contains his description of San Antonio
Springs. The words quoted in the text of this paper begin on the eighth line below the date and
end on the ninth line. The first words are nogales altísimos and the last are palmitos legítimos.
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2
Young Sabal mexicana growing in the woods of Inks Lake State Park. Tangle of threads on
leaves distinguish it from Sabal minor.
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3
Wild (escaped) reproducing population of Sabal mexicana on ranch near Medina, deep in the
Hill Country. Wild palms can be hard to see. There are at least five in this photograph.
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4
Forty-four-foot-tall Sabal mexicana growing in front of a schoolhouse in Georgetown. This tree,
probably near 100 years old, should dispel any preconceptions about the size and hardiness of S.
mexicana even hundreds of miles north of the Lower Rio Grande Valley.
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What’s Latin, What’s Local: Taxonomy of the Flora of the Southwest
Patricia Rektorik-Sprinkle
Latin Teacher (retired)
2017 Mistywood Lane
Denton, Texas 76209-2224
(940) 387-5231
[email protected]
The process of naming plants (and animals, too, in some examples) of the Southwest invites
many questions about such designations as Ilex vomitoria, Guaiacum angustifolia, and even our
well-loved Lupinus Texensis. The investigations discussed in this paper explain the linguistic
origins of some of the taxonomic designations that have been assigned to our native flora,
emphasizing three main sources in addition to the expected Greek and Latin: 1) botanists who
worked in the field, 2) aboriginal names, and 3) geographical references. The report expands on
my former work as Latin teacher with my students and with the wild-flower notebooks they
annually prepared for their science classes, as well as on cooperative ventures with the science
department for honors and AP classes. This work in turn led me to Spanish, French, and Native
American sources, as well. Subsequent presentations at workshops for practitioners of this neoLatin language provided new insights and references. For those who find themselves interested
in this topic, the bibliography provides a fairly accessible source list for further investigations.
The taxonomic designations of plants and animals learned in basic biology classes
provide one of the few exposures most people have to Latin in one of its currently most practical
applications. Everyone knows about felines and canines; the ubiquitous leaf and wildflower
collections introduce Quercus and a Heliolanthus or two, assuming Latin--maybe Greek--as the
basis for the terminology. The taxonomic labels we usually see give the genus and species, then
perhaps the variety or subspecies: Feles domesticus siamese, a Siamese housecat; Feles
concolor, the cougar.
But the explorers of our Southwest flora and fauna did not come, like the Biblical Adam,
into a world waiting for their choice of labels: The local folk--indigenous and immigrant
Hispanic alike--already had names for things. Even before the Spanish travelers arrived, of
course, the creatures had names in Nahuatl, Algonquian, and other native tongues, which have
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also left their shadows, transferred through Spanish into modern taxonomy.
When the official scientific namers made their lists, they followed the established naming
pattern for obvious entries like the coyote. Locally known as coyotl to the Nahuatl speakers, he
stayed “coyote” in the vernacular, but, being a dog, became Canis latrans—“the barking dog”-to the taxonomists. (Another possible translation could make him a “thieving dog” instead,
depending on which Latin verb you choose.) Similarly, the ocelot was tlalocelotl ( tlalli, a field
+ ocelotl, a jaguar) in Aztec. Obviously a cat, the ocelot taxonomically is Felis pardalis, “the
spotted cat.” A little knowledge of taxonomic vocabulary can lead down a false path here: an
ocellus--a “little eye”--is a spot on an animal, like those on a leopard or a peacock’s tail, but this
does not give us the vernacular “ocelot,” which is an Aztec word instead.
Our funny little friend, the roadrunner, is also known as paisano in South Texas--he’s our
“fellow countryman.” Officially in the cuckoo family--Cuculidae--he’s a Geococcyx
californianus, so at least the place name gives him a somewhat local title. Coccyx is Greek for
“cuckoo,” an echoic name; geo- is “world. Does that make him a world-class cuckoo?
No list is complete without an insect, so I submit another “californianus” designee, the
yucca borer, a common California weevil--no Latin here: he’s a yuccaborus (yucca from the
West Indian Tainu, borus from the Greek for “eater”)!!
Three major sources for the taxonomic designations for the flora of the southwest, in
addition to the expected Latin and Greek descriptors, are the botanists who researched the Texas
plant world, endemic languages of the area, and geographic references.
One of the most interesting names is that of the Indian paintbrush, Castilleja, an enigma
since I first started working with high school wildflower collections. In Spanish, castilleja
means “little castle,” but even with my imagination, the flowers don’t look anything like castles.
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Frustrated by this seemingly bad descriptor, I finally read in Wild Flowers of the Llano
Estacado, “...genus named for the Spanish botanist of the same name...” (Rose and
Strandthamm 161). Riddle solved: Juan Castilleja lives on in the Castilleja indivisa.
In fact, names of prominent early Texas botanists are preserved in the names of native
plants: Ferdinand Lindheimer, a German-born botanist who settled in New Braunfels, in the
Texas star or Lindheimer daisy--Lindheimera texana, among many other namesakes; Jean Louis
Berlandier, a French-Swiss physician collecting in the early 1800’s, in the soft green-eyes-Berlandiera pumila; Prince Maximilian of Wied Neuweid, a naturalist traveling here in the
1830’s, for the Maximilian sunflower--Helianthus maximiliani; in a more recent century, Dr. C.
C. Lundell shared honors with his wife, Amelia, by naming Amelia’s sand-verbena, Abronia
ameliae, for her; and, to the other chronological extreme, we have the anacua tree, Ehretia
anacua (also spelled Eretia) designation honoring the most famous of eighteenth-century
botanical illustrators, Georg Dionysius Ehret, who provided the pictures for Linnaeus’ texts--but
probably never came to Texas.
That flowering South Texas tree, the anacua or sandpaper tree, completes its label
with the Spanish name anachuite, drawn from the Nahuatl language of the Aztecs and meaning
"paper" and "tree," perhaps referring to the scaly peeling bark. To the English speakers of the
region, this small tree or bush is fondly known--or mispronounced--as the knockaway!
Another plant keeping its aboriginal name is the yellow trumpet flower, Tecoma stans.
According to Vines (928), "The genus name Tecoma is from an Indian name meaning "pot tree."
The species name, stans, signifies the upright habit of this plant. The nectar is reported to be
good bee food. The Indians made bows from the wood."
Also drawing on native languages, the guayule--Columbrina texensis--takes its common
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name from the Nahuatl: quauholli < quauitl,”plant” + olli, “gum.” This plant is under
cultivation for the rubber produced from its juices. (The official Colubrina Texensis designation
seems to indicate some sort of resemblance to a Texas snake, however!) Formed on that same
native word for “plant,” the guayacan, Guaiacum angustifolium, has its original name preserved
in its neo-Latin label, enhanced by the species labeling it “narrow-leaved.”
Agave in Greek means “illustrious,” but our Southwestern ones, called maguey in Spanish
and usually English, have local designations as descriptors, like lechugilla, in Spanish, meaning
“lettuce.” The maguey cenizo, “ashy” in Spanish, is Agave scabra, “rough” or “mangy” in Latin.
And the maguey or century plant with smooth, yard-long leaves and the grandest of them all, is
the Agave americana, which can soar to twenty feet.
Similarly, the whole Yucca genus comes from a Spanish version of a probably Taino
native name with Latin descriptors added: rostrata--“beaked”; angustifolia--“narrow leaved”
(the Spanish bayonet); carnerosanus--“rosey-fleshed.” (All no doubt vulnerable to the
yuccaborus californianus!)
Looking back to the californianus species designation for both Wile E. Coyote’s friend
and the previously mentioned yucca borer leads us to other place names in the taxonomy.
Continuing the geographical references, away across our Southwestern region grows the Mesa
Verde cactus, only a few inches tall, grey-green and grooved, with creamy-white, funnel-shaped
flowers. An Echinocactus, it became Echinocactus mesae-verdae, not mensae-viridinis, an
example of back-forming from the botanical world using the Spanish bases rather than the Latin
for “green tableland.” The echino- part is from the Greek for the similarly-bristly hedgehog. A
small, purple-flowered vervain is a Verbena neomexicana; the bear-grass yucca is Yucca
louisianensis; and Texas shows up in several variations: Echinocactus texensis, (the devil’s head
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or horse-crippler cactus--there is also an Echinocereus chisoensis , the Chisos hedgehog cactus);
Cnidoscolus texanus (bull nettle or mala mujer—“bad woman” in Spanish); Lindheimera
texana (Texas star); Cirsium texanum (the Texas thistle); and even Ericameria austrotecana--the
austro- part means “south--(false broomweed); and, of course, Lupinus texensis, the Texas
bluebonnet.
The story of this most Texan of wildflowers provides an insight into mistaken identities
in the plant world. In Latin, lupus means “wolf,” that rapacious beast feared by man and animal.
The legumes known as lupines were seen to thrive in poor soil. Drawing a false conclusion--that
these plants were plundering the soil of its nutrients, much as the wolf devours and destroys
everything edible--they were named lupines, the wolfish ones. That they are truly among the
most beneficial of plants for their nitrogen-fixing service which enriches, not depletes, soils, has
come much too late for renaming.
Reading the stories of our native plants in both their common names and their taxonomic
designations gives fascinating insights into not only their physical characteristics, as expected,
but also their history and folklore with their human cohabitants in the region.
Two native hollies, the possum haw (Ilex decidua) and the yaupon holly (Ilex vomitoria)
provide such information. For the first, the Latin designation is unimaginative, labeling the little
tree a “deciduous holly;” but its common name draws a picture of a possum among its branches,
eating the berries--the “haw” of the name. For the second, the Latin designation draws a
somewhat disquieting scene, telling us that the tree could provide an emetic in case of
poisoning. In Krochmal (125) we read that “Indians have made an infusion of the leaves...for
their ‘black drink’...[ a laxative which] in addition to serving as a ‘winter cleaner’ and tonic, was
slightly narcotic.” The common name, yaupon, comes from the Catawba Indian for “shrub.”
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Two more of our flowering species, the lantana (Lantana horrida) and the Texas
mountain laurel (Sopora secundiflora) seem to have warnings in their titles. For the lantana, a
member of the vervain or verbena family, that horrida simply means “rough-leaved” or “bristly,”
which a touch to the leaves confirms. The mountain laurel, however, has toxic beans, leaves,
and flowers--the warning in the sopora (“sleep-bringing”) label. It is also called mescal bean.
(The species designator, secundiflora, simply says that it has flowers on only one side of the
stem.)
To finish the story with pretty flowers, look at the Phlox cuspidatus, the pointed phlox.
Phlox comes from the Greek for “flame,” cuspidata in Latin says they have points, much like
cuspid and bicuspid teeth. Our common sunflower, Helianthus annuus, calls itself in Greek heli
(“sun”) anthus (“flower”) which grows each year, annuus in Latin. And that beloved-to-SouthTexans cenizo--“ashes” in Spanish, alternately called Texas sage, Texas silverleaf, or purple
sage--is Leucophyllum frutescens: Greek leuco “white” and phyllum “leaf,” a shrub which,
through the Latin frutescens, “becomes bushy” and turns the brush-country hills a lovely
lavender-pink after a rain. The evening primrose, Oenethera speciosa, and the wine cup,
Callirhoe digitata, wait to have their stories told--but next time.
Bibliography
Ajilvsgi, Geyata. Wildflowers of Texas. Fredericksburg, Texas: Shearer Publishing, 1984.
Bedichek, Roy. Adventures with a Texas Naturalist. Austin: University of TexasPress, 1947.
Everitt, James H., and D. Lynn Drawe. Trees, Shrubs, and Cacti of South Texas. Lubbock: Texas
Tech University Press, 1994.
Guerrero, Elias J. Scientific, Standard, and Spanish Names of Woody Plants in South
Texas. Weslaco, Texas: Starr County Soil and Water Conservation District, 1969.
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Irwin, Howard S., with paintings by Mary Motz Wills. Roadside Flowers of Texas. Austin:
University of Texas Press, 1961.
Krochmal, Arnold and Connie Krochmal. A Field Guide to Medicinal Plants. New York: Times
Books, 1984.
Loughmiller, Campbell and Lynn Loughmiller. Texas Wildflowers. Austin: University of Texas
Press, 1984.
Neal, Bill. Gardener’s Latin. Chapel Hill: Algonquian Books, 1992.
Rose, Francis L. and Russell W. Strandtmann. Wildflowers of the Llano Estacado. Dallas: Taylor
Publishing Company, 1986.
Tull, Delena, and George Oxford Miller. A Field Guide to Wildflowers, Trees and Shrubs of
Texas. Houston: Gulf Publishing Company, 1991.
Vines, Robert A. Trees, Shrubs, and Woody Vines of the Southwest. Austin: University of Texas
Press, 1960.
Wasowski, Sally. Native Texas Plants. Austin: Texas Monthly Press, 1988.
Weniger, Del. Cacti of Texas and Neighboring States. Austin: University of Texas Press, 1984.
(Thanks also to Judith Rektorik Stowers and Edgar E. Sprinkle for their research support.)
Copyright © 2006 by Patricia Rektorik-Sprinkle.
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Native Plant Society of Texas Annual Symposium
October 19-22, 2006
San Antonio, Texas
Field Trips:
Castroville Regional Park
Patty Leslie Pasztor
“South Texas Brushlands Meet the Hill
Country”
Salado Creek
Debbie Reid
“A Bioengineering/Bank Stabilization Project
Using Texas Natives”
Crownridge Canyon Natural Area
Janis Merritt
“Ethnobotany and Native Plant Identification at
Crownridge Natural Area”
San Antonio Botanical Garden
Paul Cox
“Texas Native Trail Tour”
Friedrich Wilderness Park
Lottie Millsaps
“A Hill Country Sampler”
San Antonio Missions National Historical
Park
Bill Carr
“A Plant Walk Around the San Antonio
Missions”
Friedrich Wilderness Park/ Woodland Hills
North
Dianne Hart and JayNe Neal
“Where in the World are the Native Plants:
Using GPS Technology”
Warbler Woods
Don Schaezler
“The Intersection of Ecological Zones”
Workshops:
Government Canyon State Natural Area
Catherine McKee
“It's All About the Water”
Cooking with Natives
Steven Coussoulis
Honey Creek State Natural Area
Wilt Shaw and J.W. Pieper
“An Exploratory Walk: Savannah to Riparian”
Creating a Vibrant Chapter
Helena van Heiningen, Cynthia Maguire,
Melissa Miller, Sue Wiseman
Medina River Natural Area
Dianne Simpson and E. Gail Dugelby
“Marvelous Riparian”
Drawing in the Field: Notes in Pencil and
Watercolor
Maren Phillips
Mitchell Lake Audubon Center
Iliana Peña
“South Texas Native Plants and the Wildlife
they Support”
Really Connecting People and Native Plants
Peggy Spring
Sabal Mexicana Palm Tree: Native to San
Antonio and Beyond?
Landon Lockett
Huebner-Onion Homestead Natural Area
Richard Heilbrun and Mike McDonald
“Developing a Protected Area in an Urban
Environment”
Seeking a Sense of Place
Penelope Speier
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About the Presenters
Bill Carr has studied the flora of Texas for more than 25 years. For the last ten years, he has
worked as the botanist for The Nature Conservancy of Texas, with statewide duties relating to
rare species, vegetation monitoring, and inventories of potential preserves and conservation
easements. Prior to that, he worked for eight years for the Texas Parks and Wildlife Department's
Texas Nature Heritage Program. During 2001 and 2002, he spent 45 days conducting a botanical
inventory of the San Antonio missions.
Steven Coussoulis has a BS in landscape architecture with a minor in horticulture from Texas
A&M. He has always loved to cook and learned at a very young age about cooking from his
grandfather, who emigrated from Greece and owned two restaurants in Laredo, Texas. His
mother and grandmother, who came from Mexico, also helped him develop strong cooking skills
using native plants.
Paul Cox is the senior author of Texas Trees—A Friendly Guide. He has served for 29 years as
the assistant superintendent of the San Antonio Botanical Garden.
Gale Dugelby has degrees in biology and environmental science from the University of Texas at
San Antonio. She is most interested in ecology, working for the City of San Antonio on all
aspects of the city's natural area and Edward's Aquifer protection activities. She is a certified
master naturalist and now directs the city's first natural area on its south side, the Medina River
Natural Area.
Dianne Hart is the GIS analyst for the City of San Antonio Parks and Recreation Department.
She has an MS in biology from the University of Texas at San Antonio and uses both GPS and
GIS to produce maps for the Natural Areas Division of the Parks and Recreation Department.
Among the ways that Hart uses GPS and GIS together is in adding locations of intriguing plants
and other items of interest to maps of the natural area properties, maps used by both park
biologists and volunteers. She also uses GPS to mark trails on the natural area properties and to
construct transects for vegetation surveys.
Richard Heilbrun is an urban wildlife biologist with the Texas Parks and Wildlife Department
and has assisted with the program objectives and conservation education program for the Onion
House preservation.
Mark Klym is the coordinator of the Texas Wildscapes and Texas Hummingbird Roundup
programs at the Texas Parks and Wildlife Department. After receiving baccalaureate degrees
from Lake Superior State University in Sault Ste. Marie, MI, Klym followed the hummingbirds
south to work in Texas in 1999. He has authored or edited many of the materials available from
the wildlife diversity program at TPWD, and he recently coauthored Hummingbird of Texas,
published by TAMU Press in 2005.
Eric Lautzenheiser has worked for 30 years in Texas as a horticulturist, botanist, and ecological
preserve manager. He worked with Lynn Lowrey, one of the pioneers in Texas of the native
plant nursery business. He served in Houston as director of Mercer Arboretum and Nature
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Center, executive director of Houston Audubon Society and assistant director of Armand Bayou
Nature Center. In San Antonio he has served as director of the San Antonio Botanical Gardens.
His current title is Superintendent of Nature Preserves for the City of San Antonio.
Bill Lindemann holds BS and MA degrees in geology from the University of Texas at Austin.
The current (and a former) president of the Native Plant Society of Texas, he was awarded the
Nancy Benedict Memorial Award by NPSOT for his conservation work and public service in
establishing the Fredericksburg Nature Center and its friends group. Bill teaches classes on
birding and nature for adult education programs and writes weekly newspaper articles on birding.
Landon Lockett received NPSOT’s 2003 President’s Award for research and writing
concerning Sabal mexicana and NPSOT’s 2004 Nancy Benedict Memorial Award for
preservation of a unique population of rare palms. He has written numerous papers and articles
on Sabal mexicana.
Kelly Lyons, a Trinity University professor, worked as a post-doctoral research associate at the
Universidad Nacional Autonoma de Mexico, Instituto de Ecologia in Hermosillo, Sonora,
Mexico. She earned her master’s degree in plant ecological physiology and a Ph.D. in plant
ecology from the University of California at Davis. She has studied the effects of community
diversity on the invasion process and their impact on native herbaceous species persistence and
nutrient cycling.
Mike McDonald is a geologist and a naturalist. He has been intimately involved with the
protection of the Onion House property since the inception of the preservation effort and has led
the ground movement and property improvements.
Catherine McKee has enjoyed a lifelong interest in the environment and particularly in plants.
She began volunteering in area parks in 1997 and completed master naturalist training the
following year. She leads interpretive walks at Government Canyon and particularly enjoys those
that focus on the plants. She says she mostly wants people to have a pleasant experience that will
draw them back onto the trails again to discover more about this rich resource.
Char Miller is a member of the history department and director of the urban studies program at
Trinity University. He is author of the award-winning The Making of Modern Environmentalism
and Deep in the Heart of San Antonio: Land and Life in South Texas. He is editor most recently
of On the Border: An Environmental History of San Antonio. Miller has served on the Open
Space Advisory Board and the Tree Preservation Ordinance Committee for the City of San
Antonio.
Janis Merritt works for the San Antonio Parks and Recreation Department. She leads
preservation and conservation efforts over the Edwards Aquifer and monitors acquired preserves
for general condition, incursions, and biological conditions. She previously worked at the San
Antonio Botanical Garden as the native plant curator.
Lottie Millsaps has been a long-time interpretive guide at Friedrich Wilderness Park and was
previously a trail guide at Cibolo Nature Center for many years. She was instrumental in the
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creation of the San Antonio chapter’s demonstration garden at Friedrich Park and continues to
maintain it. She received the 2004 NPSOT Fellows Award for her knowledge and contribution to
native plants and our local chapter. Self-educated and a master naturalist, she is one of the most
sought-after experts locally in field identification and interesting tidbits about our native flora.
JayNe Neal coordinates science and research for the City of San Antonio Parks and Recreation
Department natural areas. She has an MS in wildlife biology from Texas State University, San
Marcos, TX, and has been using GPS for years, including determining the geographic locations
of unusual and/or uncommon plants, mapping the habitat of the golden-cheeked warbler, and
marking the locations of black-capped vireos (both federally endangered birds).
Patty Leslie Pasztor is the co-author with Paul Cox of Texas Trees—A Friendly Guide. She has
worked for 10 years as the native plant curator at the San Antonio Botanical Garden and served
as the park naturalist at the Friederich Wilderness Park for several years.
Iliana Peña is a South Texas native, having grown up in the Rio Grande Valley. She has spent 8
years of her career specializing in South Texas habitat management and conservation education.
She has always been fascinated by South Texas plants and their ability to survive and adapt in
such an unpredictable environment. Her undergraduate and graduate degrees are in wildlife
ecology and range and wildlife science. She has been the director and land manager of the
Mitchell Lake Audubon Center since its opening in April 2004.
Mark Peterson graduated from Michigan State University and currently serves as the Texas
Forest Service’s Regional Urban Forester for the Alamo Region, which consists of 23 counties
stretching from Gonzales in the east to Crockett in the west. He provides technical and planning
assistance to municipalities, counties, defense bases, civic organizations, and individual
landowners and administers several federal grant and cost-share programs, such as oak wilt
suppression, within the region.
Maren Phillips has painted the natural world for over 30 years. She has led numerous painting
and drawing classes and workshops and specializes in students and other participants who have
no previous art experience. Her talks and examples brim with enthusiasm and energy, and she
demands a good effort! Come prepared to work hard and have a lot of fun.
J. W. Pieper worked in the banking industry for 33 years before retiring and becoming active at
Honey Creek. He was trained as a Texas master naturalist in 2003 and is actively involved in
various outdoor activities. He has served on the board of the Friends of Guadalupe River State
Park-Honey Creek for two years and as vice president and president of the friends of that same
group. Pieper currently is the treasurer. He also serves as vice president of the Alamo Area
Master Naturalists.
Pat Richardson, a research fellow at the University of Texas, works with her husband, Dick
Richardson, in integrative biology at UT. The focus of their research is on natural resource
management. Pat is currently doing videography of soil mesofauna. A strong objective of their
research is to recognize and promote the use of nature’s free tools to simultaneously build
ecological health and enhance economic well-being.
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Don Schaezler received his education in engineering, including environmental engineering, and
his professional experience has addressed many aspects of the environment. He has had a
lifelong interest in ecological topics, and that interest became more intense when he and his wife
moved to a property near Cibolo in 1997. They have become avid birders and have developed a
keen interest in other fauna and in native plants. This has led to the creation of a wildlife
preserve, Warbler Woods, which hosts about 1000 people each year. Schaezler’s knowledge of
plants is largely self-taught by reading and experience.
Wilt Shaw spent his working career as an exploration geophysicist and consultant. Currently he
is president of the Friends of Guadalupe River State Park-Honey Creek, where he has served as
an interpretive guide for over three years. He is also a member of the Cibolo Nature Center,
where he volunteers as a trail guide in the outdoor classroom program.
Mark Simmons is an ecologist for the landscape restoration program at the Lady Bird Johnson
Wildflower Center. His research focuses on solving multi-scale landscape problems using native
plants and ecological processes. He has a BS in environmental science from the U.K., an MS in
botany from Cape Town, South Africa, and a PhD. in rangeland ecology from Texas A&M. For
the last 15 years, Simmons has worked on a variety of restoration, conservation, and ecological
assessment projects in southern Africa and North America.
Dianne Simpson is a graduate of the University of Texas at San Antonio in fine arts and is a
native plant advocate for the Edwards Aquifer region. For the past six years she has been
working as a volunteer at Government Canyon State Natural Area, which, for the San Antonio
area, is an ecologically polar opposite of Medina River Natural Area, a riparian dream come true.
Jason Singhurst serves as the botanist/plant community ecologist for the Texas Parks and
Wildlife Department.
Penelope Speier is a local artist and the director of the 04ARTS Foundation, which encourages
the use of arts in education.
Peggy Spring has a master’s degree in plant ecology from the University of Georgia and 35
years of experience in environmental education with nature centers, public and private schools,
youth organizations, adult education, and environmental consulting firms. She currently serves as
a park naturalist for the City of San Antonio. One of the major emphases of the city’s education
program in the natural areas of the City of San Antonio is ethnobotany.
Bill Ward is the founding president of the Boerne Chapter of the Native Plant Society and is
professor emeritus of geology from the University of New Orleans. He is also a citizen science
research advisor at Cibolo Nature Center in Boerne.
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