Butler University Botanical Studies
Volume 5 Butler University Botanical Studies
Article 15
Forest succession in the Trout Lake, Vilas county,
Wisconsin area: A pollen study
J. E. Potzger
Butler University
Ruth R. Richards
Butler University
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The Butler University Botanical Studies journal was published by the Botany Department of Butler
University, Indianapolis, Indiana, from 1929 to 1964. The scientific journal featured original papers
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Recommended Citation
Potzger, J. E. and Richards, Ruth R. (1941) "Forest succession in the Trout Lake, Vilas county, Wisconsin area: A pollen study," Butler
University Botanical Studies: Vol. 5, Article 15.
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ervation, Indian­
diana Acad. Sci.
I
-butioll Hecords,
tI
FOREST SUCCESSION IN THE TROUT LAKE,
VILAS COUNTY, WISCONSIN AREA: A POL­
LEN STUDYl
By J. E. POTZGER, Butler University. Indianapolis, Indiana
RUTH REIlEK.'\H R1CHARDS, Milwaukee-Dowrier College,
Milwaukee, \iVisconsin
The lake Eorest in \Visconsin, and at least in parts of Michigan,
is characteriied by a contrasted variation in the dominants controlling
the crown cover in the stand; one consists of Pinus, in less favorable,
sandy habitats, the other 0 E species of the northern hardwoods (Acer
saccharum, Betula It/tea., Tsuga canadensis, and eastward also Fagus
grandifolia) , which occupy the better clay and loam soils. As pointed
out in a previous study on the Gillen Nature Reserve (5), the hard­
woods complex is the more recent invader in Vilas county and adja­
cent areas in Wisconsin and upper Michigan, perhaps even in the
whole lake forest region as indicated by pollen profiles from New
Jersey (8). Earlier pollen studies by Potzger anti Wilson (9),
Smith (11), and Moss (3) in Michigan and Indiana indicate that
a simple Pinus dominance gave way to invasion by broadleaved
genera, which in the lower latitutles consisted chiefly of Quercus.
As pointed out Ear the Gillen Nature Reserve (5), the northern
hardwoods (Tsuga, Betula, Acer [?]) replaced to a marked degTee
the long-time Pinus dominance which had superceded Picea, the first
invader after glacial retreat. The present paper is another chapter
in the study of vegetational history of the Vilas county, Wiseollsin
neighborhood, stressing this time the area immediately adjacent to
Trout lake, which as a whole is controlletl by Pinus, and revolved
in a Pinus dominance to the present time. Two smaller tracts of
forest primeval are still existing at or near the lake, viz., the Point
\Voods T. 41 N., R. 6 E., Serc. 9, and the 6O-acre tract owned by the
Dairymen's Country Club, T. 42 -:\., R. 6 E., Sec. 6 (center). The
constitution of these forests is shown in tables 1 and 2. Large acre­
age between Trout lake and for miles in all directions from the lake
'Contribution 125 from the botanical laboratory of Butler University, Indian­
apolis, Indiana; and notes and reports 109 from the Limnological Laboratory of
the 'vVisconsin Geological and N atmal History Survey, University of Wisconsin.
179
are to.day devoid of all climax forest cover, the vegetation consistrng
primarily of the low shrubs Compton/a peregrina and species of Vac­
cinium, with scattered clumps of Amelanchier, scrubby specimens of
Quercus borea.l7:.\· vaL 1ua.rim,a and luxuriant cover of Pleridium
aqm:linu'm var. latiuscu./u'l1t. There is no indication of an invasion by
hardwoods, but all seems to be marki ng time for the day when Pinus
will have advanced from centers of seed trees to take possession of
areas where it constituted the dominant tree layer for many thousands
of years. Areas adjacent to seed trees readily yield to re-occupatiOI1
by Pinus. An eighth-acre tahulation in a recelltly invaded tract
adjoining the Dairymen's Country Club forest, which had been com­
pletely denuded of trees, shows 108 stems of y,oung Pi/1NS sl1'oblls
and 4 of P'inus resinosa. The next adjoining one-eig;hth acre sup­
ported 82 stems of Pint·ls strobus and 16 of Pin1/S rr::,'illosa. Species
(If broadleaved trees were limited to depauperate stems of /tar r1.t­
brwl1'I. In view of these facts, aile wondered what the record~ in peat
would show for this region. The analysis of deposits from five bogs
included in this paper answers the question at least in part.
an in
but d
T
:-<1ltth
With
TOPOGRAPHIC AND VEGETATIONAL FEATURES
Pleistocene deposits determine the surface geology of Vilas
connty. The topography is rolling with occasional stretches of level
outwash plains. The high Vl"inegar moraine is only ahont 12 miles.
north of Trout lake. The soil for the most part is sandy or gravelly,
and so presents edaphic problems of inadequate water supply to
plants. The landscape is pitted with numerous lakes and bogs. Now
and then one encounters small patches of northern hardwoods, but
as a whole it was and still is potentially a pine territory: and the
absence of this crown cover is due to the complete destruction of
older seed trees by lumbering and subsequent fires.
BOGS STUDTED
For lack of convenient specific names, folll' of these depressions
have been designated hy alphahetical terms.
Bog A (Forestry Bog Luke). This little bog is less than Cl.,ne­
eighth of a mile north of the ·Wisconsin Limnological Laboratory, on
the State Forest Headquarters property. T. 41 N., R. 6 E., Sec. 8
(ne.. quarter). A small open pool occupies the center, but most 0 f
the mat is covered by a scrubby growth of La6x la,n:ci'na and Picca
1II,(wiana. In 1937 L. R. Wilson and E. F. Galloway (14) studied
180
I
i
(
{
l
is
consisting
'ies of Vac­
imcns of
11
P/rridiwm
im'as ion by
;when Pinus
s~es5ion 0 f
'" thousands
-ocCllpation
"aded
tract
I
heen comIUS
stroblls
acrc sup­
(I.
Species
If ..-/ec,. ru.­
Inls ill peat
1 five hogs
t.
I
of \'ilas
1es of level
It 12 miles
l' gravelly.
supply to
hogs. Now
woods, hilt
'j": and the
tl"l1ction of
lep1'cssions
than ol1e­
1'<lto1'y, on
I E .. Sec. 8
~lIt most of
aile! Picea
-1-) studied
I
I
i
an incomplete core of approximately 15 foot depth in the san~~ bog,
but did not penetrate to the original lake bottom.
The boring for the present study was made about forty feet
southeast of the pool, approximately in the center of the depression.
\Vith the assistance of Mr. V. E. l'dcKelvey. geologist with the Wis­
consin Geological and Natural History Survey, we were able to exert
sufficient pressme on the borer to penetrate the layers of fine sand
'over-lying coarse sand. Sediments were mixed with fine reddish
sand at the 24-foot level and became very sandy at the 27-foot level,
which condition persisted to the 31.5-foot level. Boring at Bog- A
represents the deepest one made in Vilas county bogs.
Bog B. The small, deep-set kettle hole promised a deeper layer
of organic matter than the 6.5 feet which we obtained. The depres­
sion is only about 200 feet across, the peat has solidified completely
and is now covered by straggling growth of P'icea mariana. It is
0.2 mile southwest of the intersection of highways M and N, on the
east side of highway 1\1 (T. 40 -::\., R. 6 E., Sec. 30 [ne. quarter]).
Bog C. The area covered by this bog is approximately 1,000 by
2,000 feet. It is an ice-block type depression flanked by steep slopes
which at some places reach an elevation of 50 to 75 feet above the
mat. The bog is in a late stage of filling. with a pond approximately
100 to 150 feet across occupying the eastern section. A guaky mat,
densely capped with Sphagnum. covers the major portion of tbe
depression. P-/:cea mariana and Lar·i.x laric-ina form a dense forest
about the rim, and have even invaded the mat in straggling colonies.
The first core was taken about 50 feet west of the pond and sand
was struck at 17 feet. A second boring about 15 feet west of the
open water yielded additional peat samples to a depth of 24 feet.
The bog is located on the east side of highway 1'1, 1.4 miles north of
U. S. 51 (T. 40 N., R. 6 E., Sec. 31 [nw. quarter]).
Bog D (Cardinal Bog). The healltifullittle bog on tbe property
of the Cardinal Resort is located <It T. 41 N., R. 6 E., Sec. 14. It
is hidden even from the nearby U. S. 51 by a dense encircling forest
made up of Picea mariana,) La.,-·ix lm'icina and Abies balsamea. An
opcn pond about 75 feet across occupies the center. The boring was
made approximately 10 feet from the open water, along the northern
edge of the pond. Total depth was 22 feet.
Grassy Lake Mat. The mat covering the southwest border of
Grassy lake may be descrihed in superlative terms with respect to
quakiness. A luxuriant growth of Sphagnum forms the carpet layer
181
It:f1gth
that in
either
while Ca:madeaplme calyculata and Myrica gale at times form dense
thickets, yielding in some places to Larix. Boring was begun close
to the open lake but moved progressively shoreward when eight feet
yielded no sample. A complete core was finally secured approxi­
mately 100 feet southwest of the open water. The exact location
is T. 42 N., R. 6 E., Sec. 4 [sc. corner]).
..
AlXU
~
~ !.
METHODS
182
~.
~
::.
~::.
~f~ ~
. '" . "" .
........
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S::'
8 ~.
CQ:
it :~
t~
il! ~.
e :~
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--~
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­
,-
}~
2r ~
­
,,:,.
"
..
,.
§ ;~
0'­
o •
.­
~~l
'->:;'
"
RESULTS
'With some di fference in degree and apparent duration of control,
all bogs except C show an initial Picea dominance, with Pinus present
from the beginning. \Ve consider the condition as to degree and
\;!
:so
Samplings were taken with the movable sleeve, cylinder-type
borer. A small portion of sediment was removed from the center
of the inside cylinder and placed into a properly labelled bottle. In
the laboratory, separation of the peat was accomplished according to
the Geisler (2) method. Glycerine jelly was used as moun,ting me­
dium. Since the forest complex in this part of vViscons'in is so
simple, only 100 pollen grains were counted for each foot-level.
Recordings kept in two 50-grain tabulations showed an almost identi­
cal percentage representation of the leading genera. An attempt was
made to separate the pollen of Pinus bank.riana from that of the other
two pines, but the recommended diagnostic characteristics did not
prove satisfactory in this study when check counts were made by
several workers in our laboratory. Our experiences were similar
to those reported by Deevey (1) in his work in Connecticut. For
this reason we list Pinus only generically. Prompted by all inquiry
from Dr. L. R. \Vilson of Cae College on our method of separating
Abies from Picea, and a subsequent detailed study of the pollen of
these two genera, we came to the conclusion that the differentiation
between the two on size of pollen, as given in Sears (10), which we
had followed in previous work, is not tenable, certainly not with
P£cea ca.nadensis, and led to the erroneous high percentages for Abies
g'iven in our previous publications. A check count was made in the
present study on all earlier tabUlations, and this places Picea into
great prominence in the lower levels while Abies becomes of minor
importance. No doubt the same change in importance of Abies in
fa vor of Picea will be true for published records of Indiana lakes aud
bogs.
-d."
L
r
.:" "
length of dominance of Picea in bog A as typical for the region, and
that in the other depressions the lowest part of the profile is missing
either because ~f boring's omitting layers of sand with pollen, (see
dense
close
feet
roxi­
tion
~
TI"'/." lor;. Thuja
Pir.ul"
Diced
Abi.er
...
n~
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:
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-type
nter
In
g to
me­
s so
eve!.
enti­
was
ther
not
by
ilar
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ttiry
ting
of
tion
we
ith
hies
the
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nor
in
nd
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.
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. . . . . '" Jo 4 ,. Ib
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o
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.... "" . . . . . f'lo.~.,b .. ~J:l ':".b:le
....
~
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PERCENfAGE
1::
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.
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",baJ'~.'u
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olo
P:;~.CC::NTAGE
183
,'10
<1'1,
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Ir
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.
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Z ,....
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-
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.
levels 26 to 31.5 for bog A) or because the boring could not be made
in the originally deepest part of the old lake basin. This latter type
of defect is likely to be true for boring in bogs C and D, when" a
pond of considerable size still ocwpied the central area of the depres­
sion. A study in progress now indicates proof of such errors in bor­
ings and the incorrect conclusions drawn from such results.
The story of vegetational succession is short in the Trout lake
area. Pinus succeeded Picea and held its dominance to the present
day (tables 1 and 2). It differs from that of the Gillen Nature Re­
serve (5) which is about 15 miles north, in that tbe northern hard­
woods have not yet invaded. Tsuga is represented by a very small
percentage in aU five pollen profiles (figs. I and 2), the Betula pollen
present resembles mostly that of Betula papyl'ifem, and thus would
be part of the Pinus dominance complex, playing an important ·role
during periods of decline of a stand, or after catastrophic destruction
of a forest. The most striking single feature of all five pro files is
the long and complete dominance by Pinus.
Quercus could best be characterized as an early invader, and per­
sisting as a non-aggressive constituent of the arboreal layer. Tables
1 and 2, likewise, reflect such a sociological status for this genus.
DISCUSSION
Northern Wisconsin and Michigan offer a splendid opportunity
for pollen ,workers to obtain actual facts on the behavior of the two
forest-cover types controlling larger or smaller areas in the lake forest
. region, and to ascertain whether the complex of coni fers and broad­
leaved genera moved as an entity or whether the broadleaved element
was a later intmsion into the uniform coni ferous dominance, con­
trolled by climate, and whether localized areas with least favorable
soil conditions had experienced fluctuation in forest dominance. The
study in the Gillen r-.~ature Reserve (5) was concerned with the
former question and this paper with the latter. The initiation of a
cool-dry following a cool-mois1. climate of the Picea dominance ap­
parently favored Pinus to the extent that it almost completely re­
placed Picea. No doubt because of greater height it reduced light
on the forest floor and so interfered with the development of seed­
lings of the intolerant Picea. The striking "sudden" disappearance
of Picea marks, perhaps, the decline of the then existing uni form
stand and the culmination of compensating reproduction of the genus.
184
Increase of Picea towards the upper foot-levels of the bogs evidently
indicates more solidi fied mat.:; and illl"asion by Ficea mariaua.
In the sandy Trout lake region. Pinus \llaintained dominance to
the present day, but increased aggre5sioll of broadleaved genera made
itsel f felt. This was pointed Ollt by Vv'ilson and Galloway (H).
It is interpreted by us as marking the initiation of moderating- climate
at which the northern hardwoods invaded and assumed cont rol in
more favorable places. Tables land 2 show that Accr saaIJanl1"1'1
Acer nlbnl,,.n, Bet-ufa /,a/,yrifcra and Quercus boreal-is var. maxi11l<t
have a fair representation in the small-size classes, but they maintain
more a position of second layer trees in the dominant rine stands. Tn
the newly invaded denuded areas east of the forest on the Dairy.
men's Clu!> property, broadleal'ed specie" wne wanting'. To judge
from the pollen profiles of the (;il1en l\'ature Reserve (S) we lllust
conclude that the climatic change which initiated Finns dominance'
has more recently undergone further changes hy way of moderated
temperatlll"e and increased moistnre. which favored an invasion by
the broadleaved fore~t. This injects the prohlem of climatic<tl1y
controlled dominance fOI: the region. \i\'cavf'r and Clements (12)
say, "The lake fore~t consists or a single association in which P·i,/,/,lS
.\:trovus,1'. 1"('Si110Sa and·Ts/,.(j(l ({/lIadc"/I,I'is are the climax dominants."
Nichols (4) takes it sti II broader. view 0 f the climatic climax when
he calls it "a mesophytic forest COllI prising a mixture 0 f evergrc'en
coniferous and decidtlOlIS broadlcavcd trecs." which involves all S!)t'­
cies, both needleleaved and hroaclleaved. alike. However, as S.")OI1
as pine constitutes almost pure stands on sanely stretches he no
longer cOJ~si~l<:'rs them clilllaric climax, hut calls them a "ph~lsio~
graphic dim·ax." This would perhaps best fit the "postclimax" of
Weaver and Clements (12). \Vhitford (13) separates the two ('le­
ments, .considers broadlea\'ed Iviih Tsuga a~ co-clQminant as climatic
climax. and pine ill the hardwoods a~sociatioll as "relics of a previous
pine forest." Pollen prJ files support this latter view. All profiles
from southern l\lichigan. ~finnesota, \Visconsin, some from Indiana.
and New Jersey (8) show a period of complete c1on'ljnance by Pinus
and a partial or entire replacement by hroadl~aved. genera. [-'rOnl
studies of pollen rrofile~ of bogs ill the various states mentioned
above, as \vell ,as from ollsen'atiolls during boyhood days in Presque
Isle county,. j'lichigan, the ~enior allthoi· bas, always I~een .impressed
with the fact that Tsuga is not a cl)-dominant with Pinus but ratl~er
ch~racteristically forril~ a 'pa'rr o'f the' later il1\'ading n~rthern hard­
j
lnity
two
orest
oad­
ent
OOn·
hie
The
the
I1f a
185
woods crown cover (see figures 1 <\nd 2. and tables 1 and 2). The
results of pollen studies force to the conclusion that Pinus in the lake
forest at present plays a role of postclimax, controlled by edaphiC'
factors. In the southern extension of the range of this forest Pinus
is today being replaced by Quercus, as a survey now in the making
will show. This is but a repetition of the fate of Pinus from Indi<\na
northward as shown with so n~onotonollsly uni form regularity in
all pollen profiles. As Potzger and Friesner (6) pointed out, the
boreal and the buffer lake forest with it, are moving northward, giv­
ing way to the climatically favored southern broadleaved element.
In more rigorous sandy habitats, as about Trout lake, Pinus is still
favored by edaphic factors, as the vast treeless areas easily yielding
to Pinus invasion, when centers of germule dissemination are avail­
able, show. The status of the pille and northern hardwoods in Wis­
consin and upper Michigan is similar to Quercus-Carya and mixed
hardwoods in central Indiana, as discussed by Potzger and Friesner
(7). There edaphic factors, primarily soil moisture, maintain a Quer­
cus-Carya dominance in a climatically-favored mixed hardwoods
region.
The rather elusive time element entering the discussion of any
pollen profile is interesting, but always a factor modi fied and often
distorted by the method of deposition itself as well as by imperfec­
tions in the sampling technique. Here enters especially the old ques­
tion, has the core penetrated to the original ancient lake bottom? All
the instruments used in bot:' boring work known to the authors fail
to take samples at all in sandy layers, or only under various difficul­
ties, at least when the sand is "ery coarse. In this respect the Wilson
(15) sampler, used in lake borings, is the most satisfactory instru­
ment to date, for it can take samples in sandy sediments. From bog
studies in 'Visconsin and lake sediments from l\linnesota, Michif;an
and Indiana, the senior author has come to the conclusion that in
sandy regions pollen of early invaders was deposited with fine sand
long before much organic matter and eventually peaty deposits par­
ticipated in the filling process. For that reason we feel that conclu­
"ions affixing time of duration to the Picea climax are, to say the
least, of very doubtful value, unless layers of fine sand are included
in the core. In the present study we feel that in all but bog A the
length of time indicated by foot-level persistence of Picea is too short,
due, very likely, to some errors in the sampling process. Vvhile the
story of vegetational history is to all appearance complete in the
186
t.hallo
ahilit.
par
shallow bog B, the time scale is much compressed. with the prob­
ability present that some parts of the time of deposition are wanting.
SUMMARY
1. The paper reports on a pollen study 0 f five bogs in the region
adjacent to Trout lake, Vilas county, ·Wisconsin.
2. Forest succession was uui formly in all bogs from Picea to
Pinus, and Pinus held complete dominance to the time represented
by the top-most level.
3. Decline of Picea and ascendency of Pinus was sudden. This
is interpreted as interference with reproduction in Picea when Pinus
replaced the old stand.
4. Diagnostic characters recommended by several workers for
separating pollen of Pinus banksiana from other species of Pinus
were found unsatisfactory when check counts were made of the
same foot-levels by several workers in our lahoratory and for that
reason Pinus is listed again as a genns only.
5. \Nhen the region considered in this study is cOInlxLred with
that occupied by the Gillen Nc;ture Reserve, 15 miles north of Trout
lake, the former area lacks the more recent climatically favored
northern hardwoods succession. The status of Pinus is described as
one of postc1imax, maintained by edaphic factors.
6. The di f ference in numbers of levels in the several bogs where
Picea showed dominance was explained on basis 0 f incomplete cores,
either because of missing layers of sand which constituted much of
early sediments. or inability to make borings in the deepest part of
the old lake basin because of open ponds.
ACKNOWLEDGMENTS
Appreciation is expressed to the \Visconsin Geological and Natural
History Survey for the opportunity given the senior author to serve
on their staff dnring the summer of 1940; to the Wisconsin Alumni
Research Foundation whose grant of funds supported the field work.
Grateful recognition is also made of the assistance rendered by
Messrs. V. E. McKelvey and Thomas H. Flanigan, members of the
staff at the Limnological Station, for assistance given in the boring
of hogs A and B.
To Miss Jane L. Goodlet, assistant in the Butler University De­
partment of Botany, we are indebted for the lettering on the graphs.
]87
LlTERATL;RE CITED
I. DEEVF.Y. EIJII'.·IRO 5. Studies on Connecticllt lake scdimelllS. .".mer. Jour.
Sci 237 :691-724. 1939.
2. GE[SLER, f'I.ORENCL .-\ new method of separat:on of fossil pollen from PC'll.
Bntler Un;v. Bot. Stud. ;) :141-146. 1935.
3. Moss, B'RON Y\!. Comparative pollen analysis of two bogs within bound­
aries of the Late Wisconsin g'laeial;on in fndiana. Hutler Univ. Bot. Stud.
~.
5.
6.
7.
8.
9.
10.
II.
12.
IJ.
1~.
15.
4 :207-216. 1940.
NIGRO!.,. G. E. The hcmlock-white pine-northern hardll'o"r1s region ni
eastern Korth .'\merica. Ecol. IG :403-422. 1935.
POTZGER,.f. E. Pollen spectra from fou" bogs on the Gillcn \'altlre Reserw
along the Michigan- Y\'isconsin sl:ltc line. Ms. 1942.
and R,IY C. 1"'1\11 sr--r:R. Plant migration in the sOLlthel'll limits of
Wisconsin glaciation ;n Indiana. Amcr. MidI. \'at. 22 :351-368. 1939.
\Vhat is climax ill central (ndiana' A five-mite quadrat study.
Butler Univ. Bot. Stud. 4 :IRI-195. 1940.
and .IA~lJ':~ 11. OTTO. ''-orest succession since decline of Late Wis­
consin glaciation in :--Tew ]nsey: A poJlen study of five bogs, Ms. 1942.
and lR.\ T. W[1.50,\,. Post-Pleistocene forest migration as indi­
cated by s(~diments [rom three deep inland lakes. I\mer. MidI. 1\'al. 25 :270­
289. 1941.
SEARS, p,\u. 1:>. Common fv"il pollen from [lit Erie nasin. Bot. Gaz.
R7 :95-106. 1930.
SMITH, \VM. i~. Pollen spectrum of Lake Cicott bog. Cass county, Indiana.
Butler Uni\'. Bot. Stud. 4 :43-54. 1937.
\VE:WEH,.T. E. and J7. E. CLEMENTS. Plant Ecology. McGrall'-Hill nook'
Company. Xew York. 1938.
\NHl'I'FORD, J-IM.RY NICHOl.. The genetic development of the forests of
northern Michigan: i\ ~tudy in physiographic ecology. Bot. Ga7.. :ll :289­
325. 1901.
\A11I.SON, L. R. and E. F. G II.!.OII .\\'. Micro [ossil succession in a bog in
northern Wisconsin. Ecol. i8 :113-118. 1937.-.
WILSON, IRA T. ,'\. ne\\' device for sampling lake sediments. Jour. 5ed.
Petrology' 11 :73-i9. 1941.
00.
"
l
lB8
our.
at.
nd·
tud.
of
n'e
37..
na.
1
I
I
,
I
,
TABLE I
Composition of the Point ,,'oDds at Trout lake based on 20 100-squ:lre-metcr
quadrats.
Size-classes of stems
Spc(:ies
Abies balsamea
Acer rubrum
A, sacchanll11
A. spicatum
Alnus incana
l\metanchier sp'
Betula lutea
B, papyrifera
Corylus rostrata
Lonicera sp?
Picca canadensis
Pinus resinosa
P, strobus
Quercus borealis
var, maxima
Thuja occidentalis
Below
inch
1
18
36
(,2
I
I
18
Abol'c
1·
5
5
54
95
(. '0
J J.
J5
I fi-~('l
'0
24
94
161
1
1
33
I
13
374
17
1
I
4
4
IS
I
11
:2
374
17
6
1
5
43
36
4
4
42
4
28
2
9
1
--
•
TOl,,1
%
F. 1.
35
90
60
5
5
60
5
53
42
60
90
30
5
100
60
55
1
5
88
TABLE II
Composition oi the pille woods on Dairymen's Country Club property based
on SO 100-square-meter quadrats.
Size-classes of stems
Above
Below
~))ecies
Abies balsamt'a
Acer rubrum
A, saccharum
Amelanchier sp'
Betula papyrifera
Corylu, rostrata
Pinus resinosa
P. strobus
Prunus pennsyhoanica
P. virginiana
Quercus borealis
var, maxima
Tsuga canadensis
r inch
J.;.
97
57
10
2
2
]01
1
10
205
103
4
1
14
4
71
3
21
I
5
%
Tot:t1
F. J,
304
167
3
27
101
78
133
I
18
8
74
74
60
10
16
44
70
94
2
16
12
:2
2
4
6-10
l I· J 5
2
7
II
1
3
5
20
1
189
r6·:!o
'0
92
5
1
21
38
41
42
9
18