United States 

4 Department of 

Agriculture 

Forest Service 

Advance S 

and Vigor on Sunriva 

Northeastern Forest a 

Experiment Station 

Research 

Paper N E 498 

1982 by David A. Marquis 
The Author 

David A. Marquis received a B.S. degree in forestry from The Pennsylvania State University in 1955, and 

M.S. and Ph.D. degrees in forest 

ecology and silviculture from Yale 

University in 1963 and 1973. In 1957 

he joined the Northeastern Forest 

Experiment Station's silviculture research unit in New Hampshire, 

where he studied problems of regeneration and thinning in northern 

hardwoods. From 1965 to 1970 he 

served on the timber and watershed 

management research staff at the 

Station's headquarters in Upper Darby, Pa. Since 1970, Dr. Marquis has 

been project leader of the silviculture research unit at Warren, Pa., 

where he heads a program of research on problems related to the 

regeneration and culture of highvalue hardwoods on the northern Allegheny Plateau. 

Manuscript received for 

publication 20 February 1981 

Abstract 

In several separate experiments, it 

was found that survival of advance 

seedlings after clearcutting in Allegheny hardwood stands is a function of initial seedling size-larger 

seedlings survive best. Age, number 

of leaves, and leaf size also were 

important determinants of survival. 

In Allegheny hardwood stands, 

where advance regeneration is 

typically less than 1 foot in height, 

seedlings that are less than 1 or 2 

inches tall, or that have fewer than 

two normal-size leaves, or that are 1 

year old should not be considered 

as established in advance regeneration assessments. Advance seedlings that originated under a shelterwood canopy survived overstory 

removal much better than seedlings 

from an uncut stand. Therefore, the 

final removal cut of a shelterwood 

sequence can be made as soon as 

there are an adequate number of 

seedlings. 
Introduction 

Advance seedlings-those 

beneath the overstory canopy before cutting-play a major role in 

the regeneration that develops after 

clearcutting in many eastern hardwood types (Smith 1962; Sander and 

Clark 1971; Trimble 1973; Leak and 

Wilson 1958). If advance seedlings 

are not present before cutting, 

clearcutting often will fail to regenerate such species as the oaks, the 

maples, white ash, black cherry, and 

basswood. In recent years, guidelines have been developed to estimate the numbers of advance seedlings required before cutting to 

achieve satisfactory regeneration after cutting (Grisez and Peace 1973; 

Sander et al. 1976). 

Size of the advance seedlings 

has an important effect on how well 

they survive and grow after cutting. 

In the oak types of the Central 

States, Sander (1972) found that oak 

seedlings less than 4.5 feet tall at 

the time of cutting do not contribute significantly to the future 

stand, because these small stems 

are overtopped by other faster growing competitors. Even larger advanced stems (2 to 6 inches dbh) 

may be required for sugar maple 

and beech to find a place in the 

main crown canopy of northern 

hardwood stands that also contain 

fast-growing intolerants such as 

black cherry (Marquis 1981). 

But under other circumstances, 

much smaller advance seedlings 

may be adequate-where competition is sparse or the species desired 

are the fastest growing of those 

present. Such is the case in the Allegheny hardwood region of Pennsylvania, where deer browsing, 

dense canopies, and lack of seed of 

some species result in understory 

vegetation composed almost entirely of small black cherry and red maple seedlings. Although most of 

these seedlings live only 3 to 5 

years and seldom exceed a height 

of 6 inches to "Ioot beneath a 

closed canopy, they grow quickly if 

released, and provide for the estabfishment of a new stand despite 

deer browsing if present in large 

numbers before cutting. Where absent, advance seedlings can often 

be established by a shelterwood 

seed cutting (Marquis et at 1975; 

Marquis 1979). 

Although these comparatively 

small seedlings seem to respond 

well to clearcutting under current 

conditions on the AIlegheny Plateau, it was not known whether this 

response held true for extremely 

young and extremely small seedlings, In making assessments of advance regeneration, we needed to 

know whether or not to count all 

ages, sizes, and species of seedlings equally, or whether some 

types survive poorly and should be 

ignored in the counts. Also, we 

needed to know how long it might 

take after the seed cut of a shelterwood sequence for seedlings to be 

well enough established to survive 

the final removal cut. To provide information needed to answer these 

questions, two experiments were 

established to determine the characteristics of seedlings that survive 

clearcutting. 

Study Methods 

In the first experiment, advance 

seedlings of seven species were located and marked in seven separate 

stands scheduled for clearcutting 

on the Allegheny National Forest. 

Attempts were made to secure 

seedlings covering a range of size, 

age, and vigor. At the time of installation, the species, height, length of 

shoot growth for the current year, 

number of leaves, length of the 

longest leaf, and shoot age were recorded. Shoot age was determined 

as accurately as possible from 

counts of bud scale scars. 

Five of the seven stands were 

cut during the dormant season; the 

remaining two were cut during the 

growing season. One full growing 

season after clearcutting of the 

overstory, the seedlings were remeasured to determine survival. 

Over half of the more than 1,300 

seedlings originally measured were 

lost to logging damage. Results are 

based on 547 seedlings that were 

relocated successfully after logging. 

Chi-square tests of homogeneity 

were used to determine differences 

in the proportion of sunriving seedlings for black cherry, sugar maple, 

and red maple. There were too few 

seedlings of the other four species 

to make meaningful tests, but data 

from these species are included to 

show trends. 

Because the range in seedling 

size and age beneath most Allegheny hardwood stands is limited, a 

second experiment was established 

where initial size and age could be 

more carefully controlled. About 500 

8-inch diameter flower pots were 

filled with a mixture that was twothirds forest soils (rototilled) and 

one-third sand. These pots were 

buried flush with the ground in a 55- 

year-old stand on the Kane Experiment Forest. Half of the pots were 

located beneath an uncut portion of 

the stand, and half beneath a portion of the stand from which twothirds of the basal area had been 

cut (heavy shelterwood seed 

cut-see Marquis 1979 for details 

on the stand and cutting treatments). Seeds of black cherry, sugar 

maple, red maple, and white ash 

were sowed in the pots in the fall of 

1971. During July of 1972, 10 pots of 

each species from each initial environment were moved to an adjacent 

clearcut area and were again buried 

flush with the soil surface. Seedlings were thinned to a maximum of 

eight per pot at the time they were 

moved. 

Similar groups of 88 pots were 

moved to the clearcut in October 

1972, July 1973, October 1973, July 

1974, and October 1974, providing 

six movement dates, each representing seedlings of different sizes 

and ages, Height and root collar 

diameter were recorded for each 

seedling at the time of movement, 

and again after each of the first two 

full growing seasons thereafter. The 

objective was to observe survival 

and growth after release of seedlings of six different age or size 

classes, after an initial establishment period under either an uncut 

or shelterwood environment. Movement of pots in July and October 

also simulated cutting during the 

growing and dormant seasons. 
Differences among treatment 

means were tested by analyses of 

variance and covariance after arcsine transformation for survival 

rates. Least squares regression 

techniques were used to relate initial seedling size to survival. Survival rates are the proportion of the 

original seedlings (usually eight) in 

each pot still alive after 2 years. 

Growth is based on the largest individual in each pot over the 2-year 

period after movement to the clearcut. 

ter than smaller ones. Initial height 

was a significant variable for black 

cherty, red maple, and sugar maple. 

Initial number of leaves was significant for black cherry, and length of 

longest leaf was significant for 

black cherry, red maple, and sugar 

maple. The other species also followed these general patterns 

(Table 1). 

In general, older seedlings survived better than younger ones; differences were statistically significant for red maple and sugar maple. 

Initial vigor, as measured by shoot 

growth during the year before cutting, was significant for red maple 

and sugar maple, but sugar maple 

seedlings with the greatest growth 

had the poorest survival. Thus, initial shoot growth is apparently a 

poor indicator of survival after clearcutting under these conditions. 

Because of these significant 

differences, it seemed possible that 

initial height, numbers of leaves, 

length of longest leaf, age, and similar characteristics might prove useful in identifying seedling classes 

with markedly different survival. To 

explore these possibilities, data for 

each species were examined and 

segregated into several classes on 

the basis of survival. These groupings illustrate the range in survival 

obtained at various levels of the initial seedling characteristics, and 

suggest ranges that could be validated with additional data (Table 2). 

Results 

There were no consistent differences in survival between areas 

clearcut during the growing season 

and areas clearcut during the dormant season, 

Experiment 1 

In the first experiment, survival 

of the various species ranged from 

38 to 80 percent. Larger seedlings 

of all species generally survived betTable I .-Precutting characteristics of advance seedlings that died 

or survived clearcutting in Experiment 1. 

Number Length Previous year Number in Percent 

Item Height of leaves largest leaf Age shoot growth sample survival 

lnches lnches Years lnches 

Black cherrya 

Died 

Survived 

Red maplea 

Died 

Survived 

Sugar maplea 

Died 

Survived 

White ashb 

Died 

Survived 

Beechb 

Died 

Survived 

Birchb 

Died 

Survived 

Striped mapleb 

Died 

Survived 

a Means not connected by a line are statistically different at the 0.05 level. 

b The small sample sizes for these species do not provide an adequate basis for evaluating results. Results of statistical tests 

are not shown. 
Table 2.-Percent survival as a 

function of initial 

characteristics, 

Experiment 1. 

- - 

Charac- Black Red Sugar 

teristic cherry maple maple 

Height 

0-2inches 58 

2-6 inches 74 

6inches+ 100 

Number of leaves 

1-2 65 

3-5 77 

6 + 100 

Length of longest 

leaf 

0-1 inch 79 

1-2inches 71 

2inches+ 88 

Age 1 year 78 

2to4years 74 

5years + 82 

Experiment 2 

An outbreak of cherry scallopshell moth in 1972 affected nearly 

all of the black cherry seedlings in 

this experiment, causing mortality 

on some and apparently reducing 

the vigor and growth of those that 

survived, Thus, black cherry responses must be interpreted with 

this insect damage in mind. 

As a result of the dense shade 

in the uncut stand, no seedlings of 

black cherry, red maple, or white 

ash survived through the entire third 

growing season there, so there were 

no seedlings of these species to 

move to the clearcut in October 

1974 from the uncut stand. Only 

sugar maple survived for the 3 full 

years under these conditions. All 

four species survived for the 3-year 

period under the two-thirds cut, so 

there are no missing data for these 

treatments. 

All of the pots moved to the 

clearcut during the first 2 years had 

eight seedlings, but some of those 

from the uncut stand during year 3 

had less than eight. There were no 

significant differences in seedling 

size among pots prior to movement 

as a result of seedling density, nor 

were there significant differences in 

growth after movement to the clearcut as a result of differences in 

seedling density. 

Effect of Initial Environment 

and Age on Survival 

The most obvious and striking 

result of this experiment is that 

seedlings started in the two-thirdscut stand survived far better after 

being moved to the clearcut than 

did seedlings started in the uncut 

stand. Differences were significant 

for all four species at the 0.01 level. 

Of the four species, sugar maple 

differed the least between the two 

initial environments. Sugar maple 

seedlings started in the uncut stand 

survived nearly as well as those 

started in the two-thirds cut, and 

survival of sugar maple seedlings 

started in the uncut stand was 

much higher than survival of the 

other species from that stand (Table 

3). 

Table 3.-Percent survival 2 

years after being 

moved to the 

clearcut as a function 

of initial environment, 

Experiment 2a 

Initial environment 

Species 

Uncut two-thirds cut 

Black cherry 12 70 

Sugar maple 78 97 

Red maple 26 91 

V\!hiteash 38 99 

a Differences among initial environments statistically significant at 0.01 level for all four species. 

Seedlings from the two-thirds 

cut were larger than seedlings from 

the uncut stand when they were 

moved to the clearcut, particularly 

for seedlings 2 or 3 years old at the 

time of movement (Appendix). Thus, 

the differences in survival between 

seedlings started in the uncut stand 

and those started in the two-thirds 

cut might be attributed to size differences rather than to initial environment. 

To test this possibility, covariance analyses were run to test differences in survival between the uncut stand and the two-thirds cut, 

using either initial height or initial 

diameter as the covariate. Results 

of these tests showed that differences in survival between the uncut 

and two-thirds-cut stands were significant-even after accounting for 

initial size-for black cherry, red 

maple, and white ash; differences in 

survival were not significant for 

sugar maple after covariance adjustment. 

The reason for better survival of 

seedlings started in the two-thirds 

cut is not clear, but may be the result of differences in root-shoot ratio between seedlings grown in 

dense shade and those in moderately high light.' Dense shade reduces 

root development much more 

severely than it does shoot development (Logan 1965; Marquis 1966). So 

the seedlings grown in the shade of 

the uncut stand probably had relatively small roots and were not as 

well equipped to meet the greatly 

increased transpiration demand after being moved to the clearcut. By 

constrast, those seedlings from the 

two-thirds cut probably had relatively large roots, and did not suffer so 

much from the increased moisture 

stress. 

This hypothesis seems to fit 

the differences in response by species as well. Sugar maple, a tolerant 

species, is much less affected in 

root growth by dense shade, and as 

previously noted, sugar maple from 

the uncut stand survived appreciably better than seedlings of other 

species from that stand. 
Interrelations Between Age 

and Initial Environment 

on Survival 

Survival was better in the older 

and larger seedlings, but only for 

seedlings that started in the uncut 

stand (Table 4). One-year-old seedlings from the uncut stand survived 

poorly, and survival of seedlings 

from there improved the older they 

were when moved. By contrast, 

seedlings started in the two-thirdscut stand survived well (over 90 percent in most cases), even if moved 

to the clearcut while only a few 

months old (Table 4). 

Effect of Initial Size on Survival 

Regressions of survival as a 

function of both initial height and 

initial diameter were calculated and 

tables were computed from these 

regressions showing the seedling 

size required to achieve 25, 50, 75, 

and 100 percent survival (Table 5). 

Effect of Season Moved 

to Clearcut on Survival 

Differences in survival between 

seedlings moved to the clearcut in 

July and those moved in October, 

as shown in the following tabulation, were not statistically significant. There was a tendency for 

leaves of seedlings moved in July to 

turn brown after being moved to the 

clearcut, but a new set of leaves 

usually developed the same year, 

and there was no obvious effect on 

survival. 

Table 4.-Percent survival after 

2 years in clearcut as 

a function of age and initial environment 

Age when 

moved to Initial environment 

clearcut 

(years) Uncut Two-thirds cut 

BLACK CHERRYa 

1 12 51 

2 17 68 

3 - 90 

SUGAR MAPLE 

1 63 98 

2 79 98 

3 9 1 97 

RED MAPLE 

1 22 97 

2 28 81 

3 33 95 

WHITE ASH 

1 38 99 

2 51 98 

3 - 99 

a Survival of cherry reduced in early 

years due to insect defoliation. 

Month Percent survival 

Uncut 213 cut 

July 38 92 

October 38 87 

Effect of Season Moved 

to Clearcut on Height Growth 

Season of year in which the 

seedlings were moved to the clearcut did have a significant effect on 

growth, and the effect was different 

depending on the initial environment (Table 6). In general, seedlings 

that started under the two-thirds cut 

exhibited greater growth if moved to 

the clearcut in July rather than in 

October. This is probably due to a 

longer growth period (2-112 growing 

seasons for the July move, rather 

than two seasons for the October 

move) in the full sunlight of the 

clearcut. These seedlings from the 

two-thirds cut had about 50 percent 

of full sunlight before being moved 

to the clearcut, and there was probably little physiological shock involved in this move. 

By contrast, seedlings from the 

uncut stand grew better if moved to 

the clearcut in October rather than 

July, despite the fact that the October move allowed less time in the 

open for growth to accumulate. 

Seedlings started in the uncut stand 

had only about 10 percent of full 

sunlight, had leaves typical of those 

on shade-grown plants, and seemed 

to suffer some physiological shock 

(leaves turning partially or completely brown, followed in some cases by 

refoliation) when moved to the 

clearcut in the middle of the growing season. Those moved after leaf 

fall in October did not appear to suffer, and produced typical sun-leaves 

the following spring. This shock of 

being moved in the middle of the 

season is probably responsible for 

the decreased growth of seedlings 

from the uncut stand, even though 

survival was not significantly 

affected. 

I 

Table 5.-Estimated seedling sizes required to obtain various survival rates 2 years after 

moving seedlings to clearcut - - 

Black cherry Sugar maple Red maple White ash Percent 

survival 

Height Diameter Height Diameter Height Diameter Height Diameter 

Feet Inches Feet Inches Feet Inches Feet lnches 
Table 6.-Height and diameter growth of seedlings from uncut quate advance regeneration if the 

and two-thirds-cut stands after 2 years in clearcuta seedlings are more than 6 inches 

tall. 

Species Uncut Two-thirds cut 

Height Diameter Height Diameter 

When making advance regeneration assessments in Allegheny 

hardwood stands in Pennsylvania, I 

recommend the following (see sizeclass definitions in Table 7): Feet Inches Feet Inches 

Black cherry 

July 

October 

Sugar maple 

July 

October 

Red maple 

July 

October 

White ash 

July 

October 

All species 

July 

October 

Tiny-do not count 

Small-Count each seedling as 1 

Medium-size black cherry-count 

each seedling-as 1-112 

Medium-size other desirable species-count each seedling as 2 

Thus, minimum stocking of advance regeneration on a 6-foot radium plot is 25 black cherry or 100 

of ail desirable species by current 

guidelines if ail seedlings are small 

(Marquis and Bjorkbom, 1982). If 

some or all are laraer, adeauate 

stocking will be achieved kith fewer a Means not connected by a line are statistically different at the 0.05 level. seedlings. 

Conclusions 

Seedling Characteristics 

and Survival First, it seems apparent that 

very small or very young seedlings 

of most species have poor survival. 

Seedlings less than 1 or 2 inches 

tall, or that have fewer than two 

leaves of normal size, or that are 1 

year old should not be considered 

in assessments of advance regeneration. 

Second, seedlings larger than 6 

inches tall survive appreciably better than seedlings in the 2- to 6-inch 

size class. Therefore, fewer seedlings would be required for adeSurvival after clearcutting is affected by initial size of advance 

seedlings, even in the Allegheny 

hardwood type of Pennsylvania 

where almost all seedlings are less 

than 1 foot tall. Very tiny seedlings 

(less than 1 to 2 inches tall, or that 

have less than two normal-size 

leaves, or that are 1 year old) survive 

poorly and should not be considered as established in advance regeneration assessments. Seedlings 

more than 6 inches tall survive appreciably better than seedlings in 

the 2- to 6-inch size class. 

Both experiments provide information on the survival of advance 

seedlings after clearcutting as a 

function of initial size, age, or other 

characteristics. In general, the two 

experiments agree quite well, 

though there are differences in the 

kinds of data available from each. I 

have subjectively reconciled results 

of the two studies to provide a 

guide Po the expected survival of advance seedlings (Table 7). 

Seedlings started under a heavy 

shelterwood canopy survived exposure to full sunlight much better 

than seedlings started in an uncut 

stand. The effect of initial cutting 

level was more important for intolerant black cherry, white ash, and red 

maple than for tolerant sugar maple. 

Age or size of seedlings was a 

much more important determinant 

of survival for seedlings from the 

uncut stand than for those from a 

heavy shelterwood cut. 

Table 7.-Estimated survival rates (2 years after final harvest) for three 

size classes of Allegheny hardwood seedlings, in percent 

Black Sugar Red White 

Size classa cherry maple maple ash Beech Birch 

Tiny 33 0 0 25 25 0 

Small 67 33 33 50 50 33 

Medium 100 67 67 100 100 67 

a Tiny: less than 2 inches tall, or fewer than two normal-size leaves for the species, 

or current-year seedling (as evidenced by visible cotyledons or primary leaves; Small: 

2 to 6 inches tall with at least two normal-size leaves; Medium: more than 6 inches 

tall with numerous normal-size leaves. 
Exposure to full sunlight during 

the middle of the growing season 

caused browning of leaves and 

some defoliation on seedlings 

started under the dense shade of 

the uncut stand. Although this did 

not result in significantly lower survival, it did reduce growth of these 

seedlings. Seedlings started in the 

light shade of the heavy shetterwood cut did not exhibit such effects. 

Advance seedlings in previously uncut stands should achieve 3 or 

4 years of age and 4 to 6 inches in 

height (or more) for best survival after clearcutting. Younger or smaller 

seedlings will not survive as well. 

Advance seedlings developed under 

heavy shelterwood cutting will survive and grow well even during the 

first year. The final removal cut can, 

therefore, be made as soon as the 

desired number of seedlings are 

present. 

Conclusions drawn here are 

based on initial survival after clearcutting, and do not necessarily imply that all species and sizes that 

survive initially will assume an important position in the next stand. 

Large differences in growth rates 

will undoubtedly relegate slower 

growing species to the understory, 

as described in the introduction. So 

perpetuation of the slower growing 

species in the main crown canopy 

of the next stand may require much 

larger advance stems than implied 

here. 

Literature Cited 

Grisez, Ted J.; Peace, Maurice R. 

Requirements for advance reproduction in Allegheny hardwoods: 

An interim guide. 1973; USDA For, 

Serv. Res. Note NE-180. 5 p. 

Leak, William B.; Wilson, Robert W., 

Jr. Regeneration after cutting old 

growth northern hardwoods in 

New Hampshire. 1958; USDA For. 

Serv., Northeast. For. Exp. Stn., 

Stn. Pap. 103. 8 p. 

Logan, K. T. Growth of tree seedlings as affected by light intensity 

I. white birch, yellow birch, sugar 

maple, silver maple. 1965; Can. 

Dep, For. Publ. 1121. 16 p. 

Marquis, David A. Germination and 

growth aal paper birch and yellow 

birch in simulated strip cutting. 

1966; USDA For. Serv. Res, Pap. 

NE-54. 19 p. 

Marquis, David A,; Grisez, Ted J.; 

Bjorkbom, John C.; Roach, Benjamin A. Interim guide to regeneration of Allegheny hardwoods. 

1975; USDA For. Serv. Gen. Tech. 

Rep. NE-f9. 14 p. 

Marquis, David A. Sheltewood cutting in Allegheny hardwoods. J. 

For. 77:540-144; 1979. 

Marquis, David A, Removal of unmerchantable saplings affects the 

development of regeneration following clearcutting in Allegheny 

hardwoods, J. For. 79:280-283; 

1981, 

Marquis, David A.; Bjorkbom, John 

C. Guidelines for evaluating regeneration before and after clearcutting Allegheny hardwoods. 

1982; USDA For. Serv. Res. Note 

N E-307.4 p. 

Sander, lvan L. Size of oak advance 

reproduction: Key to growth fob 

lowing harvest cutting. 1972; 

USDA For. Serv. Res. Pap. NC-79. 

6 P. 

Sander, lvan L.; Clark, F. Bryan. Reproduction of upland hardwood 

forests in the Central States. 1971; 

U.S. Dep. Agric., Agric. Handb. 

405. 25 p. 

Sander, lvan L.; Johnson, Paul S.; 

Watt, Richard F. A guide for evalu-' 

ating the adequacy of oak advance reproduction. 1976; USDA 

For. Serv. Gen. Tech. Rep. NC-23. 

7 P. 

Smith, David M. The practice of silviculture. 6th ed. New York: John 

Wiley and Sons; 1976. 

Trimble, G. R., Jr. The regeneration 

of Central Appalachian hardwoods 

with emphasis on the effects of 

site quality and harvesting practice. 5973; USDA For. Serv. Res. 

Pap. NE-282.14 p. 
Appendix 

Table 8.-Initial height and diameter of seedlings from uncut and two= 

thirds-cut stands at the time of movement to clearcut 

Age when moved Uncut Two-thirds cut 

to clearcut 

(years) Height Diameter Height Diameter 

Feet Inches Feet Inches 

BLACK CHERRY 

1 0.20 0.036 0.21 0.056 

2 .21 .035 -22 .055 

3 - .28 .067 

SUGAR MAPLE 

.25 .062 

.28 ,064 

.35 .074 

RED MAPLE 

.13 .037 

.16 .029 

.22 .037 

WHITE ASH 

.15 .041 

.15 .035 

-18 .040 
Marquis, David A. Effect of advance seedling size and vigor on 

survival after clearcutting. Broomall, PA: Northeast. For. Exp. 

Stn.: 1982; USDA For. Serv. Res. Pap. NE-498. 

Survival of advance seedlings after clearcutting in Allegheny 

hardwood stands is a function of initial seedling size-larger 

seedlings survive best. Age, number of leaves, and leaf size 

were also important determinants of survival. Advance seedlings that originated under a shelterwood canopy survived overstory removal much better than seedlings from an ~lncut stand. 

Therefore, the final removal cut of a shelterwood sequence can 

be made as soon as there are an adequate number of seedlings. 

Keywords: Allegheny hardwoods; clearcutt ing; advance regeneration 

.\U.S. GOVERNMENT PRINTING OFFICE: 1982-505-012:16 
Headquarters of the Northeastern Forest Experiment Station are in 

Broomall, Pa. Field laboratories are maintained at: 

@ Amherst, Massachusetts, in cooperation with the University of 

Massachusetts. 

@ Berea, Kentucky, in cooperation with Berea College. 

@ Burlington, Vermont, in cooperation with the University of 

Vermont. 

@ Delaware, Ohio. 

Durham, New Hampshire, in cooperation with the University of 

New Hlannphire. 

@ Hamden, Connecticut, in cooperation with Yale University. 

@ Morgantown, West Virginia, in cooperation with West Virginia 

University, Morgantown. 

Orono, Maine, in cooperation with the University of Maine, 

Orono. 

Parsons, West Virginia. 

@ Princeton, West Virginia. 

Syracuse, New York, in cooperation with the State University of 

New York College of Environmental Sciences and Forestry at 

Syracuse University, Syracuse. 

0 University Park, Pennsylvania, in cooperation with the 

Pennsylvania State University. * Warren, Pennsylvania.