Research in the Klamath Basin
2010 Annual Report
Grindelia- A drought-tolerant, new domestic source of
industrial resins for the Klamath Basin: 2010 Results
Richard J. Roseberg and Rachel A. Bentley1
Introduction
Background
Resinous compounds known as ‘Naval Stores’ were once used to caulk wooden
ships, but now these compounds (including turpentine, fatty acids, rosins, and their
derivatives) are used in large quantities by the papermaking industry(Thompson 1990;
Hoffmann and McLaughlin 1986). These resins are incorporated into the liquid pulp or as
a coating on the finished paper to improve color brilliance and ink permanence, while
eliminating ink ‘bleeding’. These compounds are also used in smaller amounts for
producing rubber, chemicals, ester gums, and resins for many other specialty applications
(i.e. rosin used on baseball bats and violin bows).
The primary current source for these resinous compounds is tapping old-growth
pine trees, or by grinding up their stumps after logging. The complex chemical structure
of these resins cannot be synthesized from petroleum or other simple oils. US
1
Associate Professor and Faculty Research Assistant, respectively, Klamath Basin Research and Extension
Center, Klamath Falls, OR.
Reference to a product or company is for specific information only and does not endorse or recommend
that product or company to the exclusion of others that may be suitable.
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Research in the Klamath Basin
2010 Annual Report
consumption of these resins was fairly static from the 1960s until the 1990s at about
550,000 ton/yr, but in recent years the increased demand for fine paper for ink-jet, laserjet, and copier applications as well as increased use of recycled paper have increased
demand for paper sizing chemicals, including resins.
US production (which once met the demand) has nearly disappeared. In recent
years, this need has been met by increased imports of resin primarily from China (60% of
world production), Brazil (20%) and nearby countries. These supplies are potentially
unreliable and expensive. About 60% of the world resin comes from tapping live trees
(with the remainder from grinding up tree stumps after logging), and 70% of the live tree
market is controlled by China. Since 1990, the price of gum resin has ranged between
$0.20 and $1.13/lb, with a general upward trend. Price spikes have been more common in
recent years. Except for these periodic price spikes, prices since 2000 have often been in
the range of $0.36 to $0.54/lb.
In the early 1980s, it was discovered that Grindelia camporum and related species
produce large quantities of a valuable diterpene resin (grindelic acid) that is nearly
identical to the high quality resins from pine trees (Guerreiro et al. 1981; Bohlmann et al.
1982; McLaughlin and Hoffmann 1982; Timmermann et al. 1983). G. camporum is a
perennial shrub, native of the western US, especially the central valley of California, and
seems to grow well under non-irrigated conditions (Bailey 1976; Hoffmann et al. 1984;
Hoffmann and McLaughlin 1986). In natural stands, grindelia seems to prefer soils higher
in clay content, but this may be due to the greater water holding capacity of the soil in
xeric climates rather than a preference for the drainage or texture of a clay soil per se.
Diterpene resin acids constituted between 65 and 75% of the total crude resin in the plant
(Hoffmann and McLaughlin 1986; McLaughlin 1986a, b). Studies on the heritability of
resin production indicate that genetic improvement is feasible (Dunford 1964;
McLaughlin 1986a, b; McLaughlin and Linker 1987).
In small, early tests in Arizona, experimental tetraploid lines of G. camporum
yielded up to 5.6 ton/ac biomass per year, with a crude resin content of up to 11%,
resulting in annual crude resin yields of up to 1,200 lb/ac, using between 22 and 30
inches of irrigation water (Hoffmann and McLaughlin 1986; McLaughlin and Linker
1987).
Although G. camporum received more initial interest than other species due to its
greater size, later studies identified a South American native, Grindelia chiloensis, as also
having commercial potential (Timmermann and Ravetta, 1990). For G. camporum,
glands on the surface of flowers are responsible for most of the resin production, with
less resin produced on the leaves, and almost none on the stems (Hoffmann et al. 1984;
Roseberg, 1996a). In contrast, G. chiloensis plants are typically smaller, but they have a
large number of resin glands on all above-ground plant surfaces (flowers, leaves, and
stems) and thus may also have potentially large resin production on a per acre basis.
(Ravetta et al., 1996a and 1996b).
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Research in the Klamath Basin
2010 Annual Report
Future Prospects- Likely Production Areas
Due to reasons of weather and labor markets, China is unlikely to be able to
rapidly increase their resin output if global markets expand, pointing towards likely
upward resin price pressure in the future. Looking to the future, chemical companies have
shown an increased interest in developing a stable, domestic source of these resins.
Grindelia (the generic term for both species) is likely suited to areas that are dry and
warm. Deep soils would decrease the need for irrigation, as would presence of some clay.
It is somewhat frost tolerant and a perennial, making it useful in temperate climates.
Likely areas would include western US, western Australia, northern Africa, southern
Europe, central China, and southern areas in South America. However, there may be
differences in local adaptation that could favor production of either G. camporum or G.
chiloensis, depending on the particular situation.
A brief economic analysis of grindelia’s potential follows: If grindelia resin were
conservatively valued at $0.40/lb, a biomass yield of 12 ton/ac with a crude resin yield of
1.2 ton/ac would be worth $960/ac after extraction. Due to resin extraction and
processing costs, farm gate values for raw material could be estimated at 50%, or
$480/ac. The likely reduced input costs would contribute to a farmer's net return from a
grindelia crop (mainly due to presumed reduced irrigation and fertilizer requirement)
compared to other crops. Because grindelia is a perennial, establishment costs would be
reduced, further adding to a farmer's net return (assuming good winter survival and
annual stand regrowth). Thus, the return could prove attractive in areas where the
expense or lack of irrigation water limits other crops.
Recent Research
Grindelia camporum near Medford Oregon, 1995
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Grindelia- a Drought-Tolerant, New Domestic Source of Industrial Resins for the Klamath Basin, 2010.
Research in the Klamath Basin
2010 Annual Report
After the initial studies in the early to mid-1980s confirming grindelia’s unusual
ability to produce these resins, virtually no crop research was done until the mid-1990s
when several small agronomic studies on G. camporum were begun by Dr. Roseberg at
the Oregon State University Southern Oregon Research & Extension Center (SOREC)
(Roseberg, 1996a). These studies, conducted in both sandy loam and clay soil types,
showed grindelia could grow well and persist over multiple years in that climate. Overall,
biomass yields ranged from 3.0 to 15.7 ton/ac, resulting in resin yields ranging from 750
to 3,940 lb/ac (Roseberg, 1996b).
In the mid-1990s studies were also begun on G. chiloensis in Argentina by Dr.
Damian Ravetta of the Universidad de Buenos Aires, focusing on wild plant collection,
selection, plant physiology, and agronomic work (Ravetta et al., 1996b). In the late 1990s
we also cooperated with Dr. Ravetta, comparing performance of the same G. chiloensis
cultivars in Argentina and Oregon (Roseberg and Ravetta, 2003). Since then, Dr. Ravetta
has continued with cultivar selection and improvement in Argentina, and now has several
lines that appear more promising than those available in the late 1990s. He has also
continued work on crop management aspects, such as N fertilization, air temperature,
water use, response to light intensities, and related factors (Zavala and Ravetta, 2001;
Wassner and Ravetta, 2005 and 2007).
No further research occurred in the US until 2010, when we received another
small grant to resume studies through 2011 under the very different climate conditions
found at KBREC. The South-Central Oregon region may be well suited to grindelia
because it is sunnier, yet cooler than the Rogue Valley or California’s central valley.
Previous results in Oregon suggested the possibility of achieving high biomass
production without dramatically decreasing resin content. Despite grindelia’s potential,
many agronomic requirements of grindelia and their effects on yield and resin production
are still unknown. The plant's resinous nature could make harvest with standard cutting
equipment difficult. Commercial processing procedures need to be developed, and
product development using grindelia biomass as a raw material is necessary also. Winter
survival of both G. camporum and G. chiloensis may be more of an issue in the Klamath
Basin, and both management and abiotic factors affecting survival of the various cultivars
of both species are not well understood. Other crop management practices such as plant
density, irrigation, etc. still need to be worked out for both G. chiloensis and G.
camporum. We did some preliminary tests on seed germination requirements in the
1990s, as others also did earlier on (McLaughlin and Linker, 1987; Zafar et al., 1994), but
have not yet developed dependable procedures for direct seeding in the field, as
essentially all field research to date has been done with transplants.
Objectives
Given the many unknowns involved with domesticating grindelia into a viable
commercial crop, based on limited funding resources we focused on the following
objectives for 2010 and 2011 research trials at KBREC.
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Grindelia- a Drought-Tolerant, New Domestic Source of Industrial Resins for the Klamath Basin, 2010.
Research in the Klamath Basin
2010 Annual Report
1. Evaluate growth, biomass yield, resin yield, and over-wintering persistence of
several accessions of G. chiloensis and G. camporum in the Klamath Basin.
2. Evaluate response of G. chiloensis and G. camporum to variations in plant
density, irrigation rate, and nitrogen fertilization.
Summary of Procedures
For these trials, seed of five accessions of G. chiloensis was provided by Dr.
Damian Ravetta from his germplasm collection at the University of Buenos Aires. In this
report, these are designated as “ChXXX” indicating “Chiloensis” followed by the three
digit accession number as denoted by Dr. Ravetta. Seed of eight accessions of G.
camporum was provided by Dr. Leslie Gunatilaka at the University of Arizona,
Southwest Center for Natural Products, from the stored collection of retired University of
Arizona scientist Steve McLaughlin. In this report, these are designated as “AXXX”
indicating they were originally collected in Arizona, followed by the three digit accession
number as denoted by Dr. McLaughlin. For simplicity, all these accessions will be
referred to as “cultivars” of the two species throughout this report.
During the late winter of 2010, seed for all trials was started in flats in the
greenhouse, and seedlings were transplanted to the field in spring 2010 as described
below for the various trials. All trials were conducted at KBREC (Poe fine sandy loam).
For each trial, weeds were controlled by mechanical and manual cultivation only. After
initial irrigation of all plots to encourage uniform recovery from transplantation,
irrigation rates were decided based on the Kimberly-Penman evapotranspiration (Et)
calculated by the US Bureau of Reclamation Agricultural Meteorological (AgriMet)
automated weather station located at KBREC (US Bureau of Reclamation, 2010). In the
irrigation response trial, irrigation was applied at rates and times sufficient to keep
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cumulative irrigation plus precipitation at or just above 60% of calculated Et in the ‘high’
irrigation treatment, 40% of Et in the ‘medium’ irrigation treatment, and 20% of Et in the
‘low’ irrigation treatment. In the fall, above- ground biomass was cut by hand, air-dried
and then oven-dried for a week at 30oC - 50oC, and weighed. Sub samples were separated
into the flower, stem, and leaf plant parts. All samples were shipped to Dr. Ravetta’s lab
in Argentina for resin analysis in early 2011.
In past studies at SOREC and in Argentina, we have observed improved winter
survival if plants were cut approximately 8 inches above ground surface at harvest
instead of cutting just above ground level. Leaving a short section of stem in this way
seemed to improve winter survival for G. chiloensis more than for G. camporum. To
measure whether this effect would also occur in the colder winters at KBREC, certain
plants within each plot were cut off at either 8 inch height or at ground level and their
survival and performances were tracked separately in 2011. For each experiment and
treatment, over-wintering survival rate was measured on May 27, 2011.
In addition to the trials described below, the trial designed to measure grindelia’s
response to nitrogen fertilizer was also set up and transplanted in spring, 2010. This trial
included one G. camporum and two G. chiloensis cultivars, all grown in the ‘medium’
irrigation treatment. The N fertilizer treatments were not applied to this trial in 2010 due
to the overall small plant size for both species by mid-summer. It was decided to
postpone these treatments until the 2011 growing season to measure the impact of N on
larger (higher yielding) plants which we expected to observe in the second year (2011),
and thus results from the nitrogen response trial will not be discussed further here, but
will be discussed in the 2011 report.
All measured parameters were analyzed statistically using SAS® for Windows,
Release 9.1 (SAS Institute, Inc.) software. As appropriate, analysis of variance was
calculated according to the individual experiment’s design. Treatment significance was
based on the F test at the P=0.05 level. If this analysis indicated significant treatment
effects, least significant difference (LSD) values were calculated based on the student’s t
test at the 5% level.
I. Plant Density x Cultivar Trials
Materials and Methods
Because G. camporum is typically a much larger plant than G. chiloensis, the
range of likely plant densities would not be equal in most cases. Because the two species’
plant spacing treatments were usually not equivalent (and thus not directly comparable),
statistics for the two species were analyzed separately.
One G. camporum (A173) and two G. chiloensis cultivars (Ch743 and Ch775)
were transplanted in rows to create four densities. The two G. chiloensis cultivars
reportedly have similar plant architecture but different resin contents, which would allow
us to evaluate how growth and resin yield may vary for high and low resin plants and
plant parts as a function of plant density (Damian Ravetta, pers. comm., 2010). For G.
chiloensis, the four between-row and within-row plant spacings were 12 x 30 inch; 12 x
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Grindelia- a Drought-Tolerant, New Domestic Source of Industrial Resins for the Klamath Basin, 2010.
Research in the Klamath Basin
2010 Annual Report
20 inch; 12 x 12 inch; and 12 x 8 inch. The four between-row and within-row plant
spacings for G. camporum were 30 x 60 inch, 30 x 30 inch, 12 x 30 inch, and 12 x 12
inch. For both species, each density treatment was replicated four times. Whenever
possible, plants harvested for resin analysis or biomass were taken from the interior of a
given plot to minimize edge effects. Thus, G. camporum data was analyzed as a
randomized complete block design, and G. chiloensis data was analyzed as a complete
factorial design, with cultivar and density as the two factors.
G. camporum was transplanted to the field on June 23 when most plants were
about 3-4 inches tall with 4-6 leaves. G. chiloensis was transplanted to the field on July 6
when most plants were about 2-3 inches tall with 3-5 leaves. The entire trial was grown
in the ‘medium’ irrigation treatment, which received a total of 1.40 inches of rainfall plus
20.42 inches of irrigation from June 1 through October 31 (Table 1). Most of the
irrigation was applied in June and July to ease transplant shock in the warm summer
weather until plants were established.
On November 7, individual leaves were collected from representative plants
within each plot to allow calculation of mean surface area per leaf. On November 16, a
single ‘typical plant from the interior of each G. camporum plot, and two typical plants
from the interior of each G. chiloensis plot was harvested, dried, and separated into plant
parts (flower, leaf, and stem) as described above, and later shipped to Argentina for resin
analysis. Equipment problems, personnel issues, and international payment restrictions
have delayed resin analysis, so resin data is not reported here. That data will be added to
the report as soon as it is available and analyzed.
Results and Discussion
Grindelia camporum
Grindelia camporum near Klamath Falls, OR, 2010
Plant spacing did not have a significant effect on biomass yield per plant, but
there was a significant difference due to plant spacing for biomass per acre as well as
stem and leaf percent of biomass (Table 2). Thus the biomass yield was primarily
controlled by number of plants per acre rather than size of individual plants, suggesting
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Research in the Klamath Basin
2010 Annual Report
that maximum plant density was not achieved in this first year. The maximum mean
treatment yield of just over 5 ton/ac (for the12 x 12 inch spacing) is lower than measured
in mature grindelia stands in previous trials at SOREC, suggesting that larger yields may
occur in the second year if winter survival is satisfactory. The small number of flowers
also suggests plants did not have time to reach full size in the short period of active
growth in the field in 2010. Plant spacing did not have a significant effect on flower
percent biomass, but the differences for stem and leaf percent biomass were both
significant. For some reason, G. camporum plants in the 30 x 30 inch spacing treatment
grew taller (data not shown) with relatively more stem and less leaf biomass than in the
other spacing treatments.
Grindelia chiloensis
Grindelia chiloensis near Klamath Falls, OR, 2010
Plant spacing did not have a significant effect on biomass yield per plant, but
there was a significant difference in biomass yield per acre due to plant spacing (Table 2).
G. chiloensis followed a pattern of biomass yield similar to G. camporum: higher density
(closer spacing) resulted in higher biomass yield, suggesting that maximum plant density
was not achieved in this first year. Plant spacing did not have a significant effect on
partitioning of plant parts, although differences in percent stems was almost significant
(P=0.066).
There was a significant cultivar effect on biomass yield, flower percent, and leaf
percent. For biomass yield, there was also a significant interaction between cultivar and
spacing, so that the main significant cultivar yield effect was the higher biomass yield for
Ch743 at the closest plant spacing only. Ch743 seemed to mature sooner, resulting in
proportionally more flowers than for Ch775. In contrast, Ch775 tended to have
proportionally more leaves at most row spacings.
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II. Irrigation Rate x Cultivar Trials
Materials and Methods
As in the plant density x cultivar trial described above, the two species were not
inter-randomized and their statistics were analyzed separately.
Eight G. camporum (A086, A121, A153, A165, A170, A171, A173 and A175)
and five G. chiloensis cultivars (Ch743, Ch775, Ch750, Ch766, and Ch734) were
transplanted within the three irrigation treatments described above. In some cases the
number of plants per plot had to be adjusted due to limited number of plants for some
cultivars. Among the G. camporum cultivars, only A173 had enough plants to allow plot
replication (4 reps), but the G. chiloensis cultivars each were replicated from 2 to 4 times.
Irrigation was applied uniformly through July to decrease transplant shock since
transplantation occurred during warm mid-summer conditions (June 23 for G. camporum
and July 6 for G. chiloensis), the same as the plant density x cultivar trial above (Table
1). After July, the irrigation treatments were imposed. Plant spacing was 30 x 30 inch for
G. camporum and 12 x 20 inch for G. chiloensis in all cases (equal to the second widest
spacing in the density x cultivar trial above). Data for both species was analyzed as a split
plot design, with irrigation rate as the main plot and cultivar as the sub-plot. For G.
camporum, the lack of plot replication for all cultivars but A173 prevented statistical
comparison between cultivars, but observations of multiple plants of the other seven
cultivars were possible.
As in the density x cultivar trial described above, individual leaves were collected
from representative plants within each plot on November 7 to allow calculation of mean
surface are per leaf. On November 16, a single ‘typical’ plant from the interior of each G.
camporum plot, and two typical plants from the interior of each G. chiloensis plot was
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Grindelia- a Drought-Tolerant, New Domestic Source of Industrial Resins for the Klamath Basin, 2010.
Research in the Klamath Basin
2010 Annual Report
harvested, dried, and separated into plant parts (flower, leaf, and stem) as described
above, and later shipped to Argentina for resin analysis. Equipment problems, personnel
issues, and international payment restrictions have delayed resin analysis, so resin data is
not reported here. That data will be added to the report as soon as it is available and
analyzed.
Results and Discussion
Grindelia camporum
Irrigation rate had a significant effect on biomass yield per plant, as well as
biomass yield per acre (Table 3). In general, plants grew well even in the ‘low’ irrigation
treatment, although increasing irrigation did seem to increase yield somewhat. As in the
plant density trial, biomass yields were low compared to previous trials at SOREC. There
was also a significant difference in percent flowers in the biomass. Increasing irrigation
seemed to delay maturity (reduced proportion of flowers) but this was not true for all
cultivars. Differences in percent stems and leaves due to irrigation rate were not
significant.
Without replication we cannot make firm conclusions about cultivar differences.
However, it appears that in these observational plots, cultivars A153 and A175 were not
as vigorous as the others, and that A170 did not grow well unless it received ‘medium’ or
more irrigation. The most commonly tested cultivar (A173) performed well in this group,
but others such as A086, A165 and A171 deserve further evaluation.
Grindelia chiloensis
Irrigation rate did not have a significant effect on biomass yield, flower percent,
or stem percent (Table 3). Effect of irrigation was significant for leaf percent, with the
highest leaf percent occurring in the ‘low’ irrigation treatment.
Yield differences between cultivars were significant. Ch743 had consistently good
yield under all irrigation regimes. Other cultivars had variable performance. For example,
Ch734 had the lowest yield under ‘high’ and ‘low’ irrigation, but had the highest yield
under ‘medium’ irrigation. Biomass yields in general were low compared to previous
studies at SOREC, likely due to the short 2010 growing season. This was demonstrated
by the significant difference in flowering percent between cultivars. Some cultivars did
not reach flowering stage at all, and flowering percent was low across the board,
indicating that G. chiloensis, like G. camporum, did not reach maturity by the fall harvest
in 2010.
Summary
The short growing season after transplanting in 2010 resulted in insufficient time
for both G. camporum and G. chiloensis to grow fully and reach maturity, resulting in
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Research in the Klamath Basin
2010 Annual Report
low per-plant biomass and few flowers. Thus, biomass yield per acre was primarily
controlled by plant spacing. Grindelia grew well even under the ‘low’ irrigation
treatment, although some additional irrigation seemed to improve G. camporum’s growth
somewhat. Some less-studied G. camporum cultivars deserve further investigation. Once
the resin data are available, more definitive recommendations as to favored plant spacing,
irrigation, and cultivar should be possible for both G. camporum and G. chiloensis.
Overwintering survival and yield data to be collected in 2011 should also further
elucidate the optimum management practices for this potential crop. Based on this
preliminary data it appears the grindelia may have a place in the Klamath Basin under
conditions of limited irrigation, but further investigation is necessary to either validate or
disprove this tentative conclusion.
Acknowledgements
Special thanks to the following for their assistance with this research:
Damian Ravetta, Universidad de Buenos Aires, Argentina for providing the G. chiloensis
seed and for performing resin analysis on harvested plant samples.
Dr. Leslie Gunatilaka (University of Arizona, Southwest Center for Natural Products),
and Dr. Steve McLaughlin (University of Arizona, retired) for providing the G.
camporum seed.
Partial funding for this research was provided by Agricultural Research Foundation Grant
#ARF 7314.
References
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Bohlmann, F., M. Ahmed, N. Borthakur, M. Wallmeyer, J. Jakupovic, R.M. King, and H.
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Dunford, M.P. 1964. A cytogenic analysis of certain polyploids in Grindelia
(Compositae). Am. J. Bot. 51:41-61.
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diterpenicos en Grindelia pulchella y G. chiloensis Cabr. Rev. Latinoam. Quim. 12:7781.
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Klamath Basin Research and Extension Center
Grindelia- a Drought-Tolerant, New Domestic Source of Industrial Resins for the Klamath Basin, 2010.
Research in the Klamath Basin
2010 Annual Report
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Ravetta, D.A., A. Anouti, and S.P. McLaughlin. 1996a. Resin production of Grindelia
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Ravetta, D.A., F. Goffman, E. Pagano, and S.P. McLaughlin. 1996b. Grindelia chiloensis
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J. Janick, ed. Progress in New Crops. ASHS Press, Alexandria, VA.
Roseberg, R.J. and D.A. Ravetta. 2003. Yield and resin production of Grindelia
camporum and G. chiloensis accessions grown in Patagonia, Argentina, and Oregon,
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and R.E. Klenck. 1983. Grindelane diterpenoids from Grindelia camporum and
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Klamath Basin Research and Extension Center
Grindelia- a Drought-Tolerant, New Domestic Source of Industrial Resins for the Klamath Basin, 2010.
Research in the Klamath Basin
2010 Annual Report
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Table1.2010Precipitation&irrigationforthegrindeliairrigationratexcultivartrial.
KlamathBasinResearch&ExtensionCenter,KlamathFalls,OR.
Month
Precipitation
(inch)
"Wet"Block
"Medium"Block
"Dry"Block
Irrigation
Irrigation
(inch)
Applications
Irrigation
Irrigation
(inch)
Applications
Irrigation
Irrigation
(inch)
Applications
June
0.52
3.91
3
3.91
3
3.91
3
July
0.15
11.17
12
11.17
12
11.17
12
August
0.23
4.72
5
3.36
5
1.32
2
September
0.05
2.64
3
1.98
2
0.99
1
October
0.45
0.99
1
0.00
0
0.00
0
Total
Total After Irrig. Treatments Began
1.40
0.73
23.43
8.35
24
9
20.42
5.34
22
7
17.39
2.31
18
3
______________________________________________________________________________
Klamath Basin Research and Extension Center
Grindelia- a Drought-Tolerant, New Domestic Source of Industrial Resins for the Klamath Basin, 2010.
Research in the Klamath Basin
2010 Annual Report
Table2.2010Grindeliaresponsetoplantingdensity,species,andcultivarundermedium
irrigationrate.KlamathBasinResearch&ExtensionCenter,KlamathFalls,OR.
Grindeliacamporum,cultivar A173
PlantSpacing
DryWt
(g/plant)
BiomassYield
(lb/ac) (ton/ac)
Flower
Yield(%)
Leaf
Stem
12x12
106
10182
5.09
5.3
89.5
5.3
12x30
114
4385
2.19
4.5
90.9
4.5
30x30
30x60
154
92
2363
710
1.18
0.36
3.3
5.5
53.8
88.9
42.8
5.5
Mean
117
4410
2.20
4.7
80.8
14.5
0.089
<0.001
<0.001
0.137
<0.001
<0.001
NSD
26.1
3368
47.7
1.68
47.7
NSD
27.2
5.2
4.0
3.8
16.2
P Value
LSD (0.05)
CV (%)
Grindeliachiloensis,cultivars Ch743&Ch775
Cultivar
Ch743
Ch775
Plant
DryWt
Spacing (g/plant)
BiomassYield
(lb/ac) (ton/ac)
Flower
Yield(%)
Leaf
Stem
12x8
19.4
2789
1.39
9.4
77.6
13.0
12x12
17.2
1648
0.82
7.8
77.4
14.8
12x20
19.7
1133
0.57
6.7
72.3
21.0
12x30
19.1
734
0.37
6.1
80.6
13.3
12x8
11.4
1639
0.82
0.0
77.8
22.2
12x12
19.1
1838
0.92
0.0
90.5
9.5
12x20
12x30
19.5
18.3
1126
701
0.56
0.35
6.8
2.7
79.6
83.3
13.6
14.0
18.0
1451
0.73
4.9
79.9
15.2
0.196
0.019
0.019
0.034
0.037
0.677
NSD
205
0.10
4.7
5.4
NSD
0.152
<0.001
<0.001
0.819
0.145
0.066
Mean
P (Cultivar)
LSD (0.05)‐ Cultivar
P (Spacing)
LSD (0.05)‐ Spacing
P (Cultivar X Spacing Interaction)
CV (%)
NSD
290
0.14
NSD
NSD
NSD
0.066
20.6
<0.001
19.4
<0.001
19.4
0.466
130.8
0.351
9.3
0.006
30.4
______________________________________________________________________________
Klamath Basin Research and Extension Center
Grindelia- a Drought-Tolerant, New Domestic Source of Industrial Resins for the Klamath Basin, 2010.
Research in the Klamath Basin
2010 Annual Report
Table3.2010Grindeliaresponsetoirrigationrate,species,&cultivar.
KlamathBasinResearch&ExtensionCenter,KlamathFalls,OR.
Grindeliacamporum
Irrigation
High
Medium
Low
Cultivar
BiomassYield
Yield(%)
DryWt
Leaf
Stem
(g/plant) (lb/ac) (ton/ac) Flower
A086
287
4417
2.21
1.7
49.9
48.3
A121
288
4433
2.22
0.0
58.0
42.0
A153
32
487
0.24
0.0
100.0
0.0
A165
364
5586
2.79
1.4
51.2
47.5
A170
244
3746
1.87
0.0
59.7
40.3
A171
326
5004
2.50
1.5
48.8
49.6
A173
264
4065
2.03
2.0
49.6
48.4
A175
180
2768
1.38
0.0
65.8
34.2
A086
349
5356
2.68
1.4
51.0
47.5
A121
110
1690
0.85
0.0
56.0
44.0
A153
32
488
0.24
0.0
100.0
0.0
A165
167
2568
1.28
3.0
59.9
37.1
A170
166
2544
1.27
0.0
66.1
33.9
A171
178
2738
1.37
2.8
57.4
39.9
A173
154
2362
1.18
3.3
53.8
42.8
A175
79
1213
0.61
0.0
68.4
31.6
A086
110
1686
0.84
4.6
60.9
34.6
A121
109
1674
0.84
4.6
59.8
35.7
A153
61
933
0.47
0.0
91.8
8.2
A165
216
3317
1.66
2.3
58.1
39.6
A170
52
807
0.40
0.0
80.6
19.4
A171
257
3950
1.98
2.0
61.1
36.9
A173
A175
215
81
3308
1242
1.65
0.62
2.5
0.0
49.4
65.8
48.1
34.2
Mean
P (Irrigation)
189
2897
1.45
1.7
60.1
38.2
0.011
0.011
0.011
0.021
0.555
0.352
59
908
0.45
0.6
NSD
NSD
CV Irrigation (%)
30.0
30.0
30.0
36.4
8.6
13.7
P (Cultivar)
nm*
nm*
nm*
nm*
nm*
nm*
LSD (0.05)‐ Cultivar
nm*
nm*
nm*
nm*
nm*
nm*
CV Cultivar (%)
P (Irrigation X Cultivar Interaction)
nm*
nm*
nm*
nm*
nm*
nm*
nm*
nm*
nm*
nm*
nm*
nm*
LSD (0.05)‐ Irrigation
* nm = Not measured due to non‐replication of most varieties.
Grindeliachiloensis
Irrigation
High
Medium
Low
Cultivar
BiomassYield
Yield(%)
DryWt
Leaf
Stem
(g/plant) (lb/ac) (ton/ac) Flower
Ch743
24.7
1421
0.71
4.7
78.2
17.1
Ch775
14.0
807
0.40
0.0
82.2
17.8
Ch750
13.9
802
0.40
0.0
80.2
19.8
Ch766
20.3
1172
0.59
5.6
75.8
18.6
Ch734
10.3
591
0.30
0.0
75.6
24.4
Ch743
19.7
1132
0.57
6.7
72.2
21.0
Ch775
19.5
1126
0.56
6.8
79.6
13.6
Ch750
18.3
1052
0.53
0.0
79.2
20.8
Ch766
12.9
744
0.37
19.4
61.3
19.4
Ch734
21.6
1244
0.62
11.6
76.1
12.3
Ch743
21.0
1211
0.61
4.0
84.7
11.3
Ch775
18.3
1052
0.53
0.0
86.3
13.7
Ch750
14.0
806
0.40
0.0
92.1
7.9
Ch766
Ch734
15.0
13.1
864
756
0.43
0.38
0.0
0.0
81.0
89.5
19.0
10.5
Mean
17.7
1019
0.51
3.5
80.4
16.1
P (Irrigation)
0.559
0.559
0.559
0.600
0.014
0.120
LSD (0.05)‐ Irrigation
NSD
NSD
NSD
NSD
6.0
NSD
CV Irrigation (%)
29.8
29.8
29.8
237.1
8.2
56.6
P (Cultivar)
0.042
0.042
0.042
0.005
0.276
0.549
6.0
347
0.17
4.2
NSD
NSD
27.9
0.373
27.9
0.372
27.9
0.372
108.0
0.215
11.1
0.947
52.2
0.942
LSD (0.05)‐ Cultivar
CV Cultivar (%)
P (Irrigation X Cultivar Interaction)
______________________________________________________________________________
Klamath Basin Research and Extension Center
Grindelia- a Drought-Tolerant, New Domestic Source of Industrial Resins for the Klamath Basin, 2010.