Age, growth patterns, spacing, and land use history of an Eastern White pine
(Pinus strobus) population in Range Pond State Park, Poland, Maine.
Cara Howieson, Erika Cyr, Jessica Otis, and Aurora Dibner- Bio 270- Bates College
Size, Age, and
Spacing
Abstract
Height on DBH 42-53 YO and 54-65 YO
25
20
 The existence of canopies for part or all of the
lives of the White pines at this site likely explains
the similar growth patterns of all age groups.
 Natural thinning related to population density,
the ice storm of 1998, drought in the early 1970’s,
and poor soil quality probably all contributed to the
high mortality of White pines in the stand.
15
10
10
5
5
suppressed
0
0
0
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26
30
40
50
60
Finished at last!
(54-65 YO)
RY
1939-1947
20
Frequency (%)
The study site is a mixed species, secondary (?) growth forest
on the northeastern border of Range Pond State Park in
Poland, Maine (Fig. 1) located at latitude 44 1’ 40’’N and
longitude 70 21’ 36’’ W. The soil of this flat terrain is
categorized as “Adams Series”, loamy sand characterized by
low natural fertility, and poor moisture-retention. The Eastern
White pine is the dominant species at Range Pond State Park
and constitutes 67% of the living stand, while the Red Maple
and Red Oak constitute 19% and 8% of the population,
respectively. Approximately 40-60% of standing pine stems are
dead trees, most of which are in the understory.
20
Figure 5. In the 42-53 year old and 54-65 year old age
clusters, there is a similar pattern of primary and
secondary growth consistent with our field
observations.
N=119 trees.
Figure 2. The White pines exhibited relatively uniform height
structure (even-sized) across all ages. We estimated the
canopy consisting of trees that were  16m tall. N=115 trees.
Figure 1. Location of the study site in Range
Pond State Park in Poland , Maine.
10
DBH 42-53
Height (m)
Site Description
(42-53 YO)
RY
1948-1959
15
Land use history
10
5
(37 - 40 YO)
RY
1960-1968
0
34
37
40
43
46
49
52
55
58
61
64
67
70
73
76
79
Age (yrs.)
Figure 3. The age structure of the White pine population contains
three major age groups: the first established from 1939 to 1947,
the second group established from 1948-1959 and the last mature
pines recruited in the late sixties. Following strong establishment
from 1939 to 1959 recruitment drops off and stops by 1968. X
value = bin center. N=114 trees.
A
Literature Cited
Sampling Plan
Abrams, M. 2001. Eastern White Pine Versatility in the Presettlement Forest.
BioScience 51(11): 967-979.
Age
30
p < 0.0001
25
Characteristics measured on each White pine:
p = 0.0041
Height (m)
50
0
20
10
0
42-53 YO
54-65 YO
75
Brower, J.E. and J.H Zar. 1984. Field and Laboratory Methods for General
Ecology. 2nd ed. Wm. C. Brown Publishers, Dubuque, IA. 226p.
50
B
25
Lancaster, K.F. and Leak, W.B. 1978. A silvicultural guide for white pine in the
northeast. For. Serv. Gen. Tech. Rept. NE-41, 13 p.
0
42-53 YO
54-65 YO
Age Group
Age group
Bormann, F.H. 1965. Changes in the growth pattern of white pine trees
undergoing suppression. Ecology 46(3):269-277.
mean Internode BH
Internode distance (cm)
Height
75
Mean age (yr)
Six transects of unspecified length were set up parallel to
Plains Road. All trees of at least 3 cm stem diameter which fell
within one meter to either side of the transect lines were
included until 20 White pine had been sampled on each
transect.
42-53 YO
54-65 YO
Age Group
 Stem height (m) and internode distances to describe
primary growth characteristics
Mean NND
40
3
30
2
1
 Age (yrs.) was measured from core samples
 Nearest Neighbor Distances (m) for White pines or
hardwoods was measured to describe the effects of spatial
distribution on growth
p < 0.0001
Acknowledgements
20
10
0
0
42-53 YO
54-65 YO
Age Group
 Whorl counts were measured to describe age
characteristics
DBH
4
DBH (cm)
 Diameter Breast Height (cm) to describe secondary
growth
characteristics
NND (m)
White pines are early invaders of gaps in forests
following disturbances due to their ability to occupy a wide
range of soil, moisture, and lighting conditions. These
conditions influence the growth and aging patterns of White
pines. White pines grow on nearly all soil types except poorly
drained soil where White pines occur only as individuals or
small groups. On disturbed sites with sandy loams or silty
loams White pine grows well and with little hardwood
competition (Abrams 2001).
White pines are only moderately shade tolerant; White
pines that are not in crowded conditions and have plenty of
light may grow up to 50-100cm in height and produce many
heavily foliated lateral branches. White pines, in crowded, low
light environments, exhibit increased primary growth relative
to secondary growth resulting in tall, thin morphology or
growth form (Bormann 1965). White pines self-prune, a
process that occurs when the lower branches die back due to
poor light availability. Self pruning results in live foliage being
limited to the crown of the tree (Lancaster and Leak, 1978).
White pines are an early to middle successional species,
which rapidly colonize land following disturbances such as
agricultural abandonment, fire, and blow-downs. The White
pine age structure established after a large-scale disturbance
generally has a narrow age range due to rapid recruitment.
(Abrams 2001).
We investigated the age, size and spacing of a White
pine population in Range Pond State Park, Poland, Maine, to
characterize the population and infer the abiotic and biotic
factors that have influenced its development.
Height (m)
15
Methods
Introduction
Height 42-53
Height 54-65
 The age and species composition of the stand
are consistent with typical New England early
successional, pine-dominated forests.
20
Number of Trees
We characterized the age, growth patterns and spacing
of a population of Eastern White pines (Pinus strobus) in
Range Pond State Park, Poland Maine. Using transect survey
techniques the age, diameter at breast height (1.37m), height,
nearest neighbor distances, the lengths of three internodes at
breast height and above, and species composition in our
sample were measured. Two major age groups were identified
by frequency analysis (42-53 years and 54-65 years old). The
population consisted of tall, thin trees with minimal foliage.
The White pines exhibited similarity in size, spacing, and
growth patterns despite differences in age. Aerial
photographs from 1949 and 1964 revealed that the 54-65 year
old White pines initially grew under a canopy of large trees
which probably caused growth suppression. This population
of large canopy trees was later cut. We believe that the
similarity in growth morphology resulted from growth and
recruitment under an established overstory.
Growth patterns
Conclusions
42-53 YO
54-65 YO
Age Group
Figure 4. Comparison of mean (± 1 SD) age, size, and spacing characteristics
of the 42 - 53 YO and 54 - 65 YO White pine age groups. N = 105 trees except
NND for which N = 102 trees. Nearest neighbor distances to White pines (live
or dead) from sampled White pines were used to calculate the Holgate
Coefficient of Spatial Dispersion (Zar ) which indicated that White pines are
distributed randomly.
Figure 6. Aerial photos of the area around the study site
from A) 1949 and B) 1964 show that a mature stand of
trees on the site were harvested between 1949 and 1964.
The yellow triangle marks trees that were not cut and
acted as a size reference for changes in the stand near
them. The red rectangle marks the actual study area.
Many thanks to all of the students in the 2003 Bio 270 class for
braving the snow and inclement weather. Thanks also to Sharon
Kinsman for her ongoing guidance and support. Kathy Claerr,
thank you for your help in species identification. A very special
thanks to Greg Anderson for all of his time, advice, and
technological support. Thanks to Mike Buffo, Katie Whorf and
Julia Briedis for your assistance. We gratefully acknowledge the
State of Maine Department of Conservation, Bureau of Parks and
Lands, for allowing access to Range Pond State Park. The USDA
Service Office in Lewiston provided access to their collection of
aerial photos for which we are most grateful.