United States 

Department of 

I Agriculture 

Forest Service 

Six-Year Beechnut Production 

in New Hampshire 

Northeastern Forest 

Experiment Station I 

Research Paper NE-677 William B. Leak 

Raymond E. Graber 
Abstract 

Beechnut production and losses were studied over a 6-year period in 41 northern 

hardwood stands ranging in age from 10 to 140 years. Production increased 

consistently with stand age or d.b.h. of dominant trees and with percentage of basal 

area composed of beech. Losses to insects, rodents, and birds before the seed 

reached the ground ranged from 24 to 100 percent; insects caused the greatest 

losses. A good seed year occurred about every third year. 

The Authors. 

WILLIAM B. LEAK is a research forester with the Northeastern Forest Experiment 

Station at Durham, New Hampshire. With B.S. and M.F. degrees from the State 

University of New York College of Forestry, he joined the Northeastern Station in 

1956 and conducts research on site evaluation, silviculture, and ecology of northern 

hardwoods. 

RAYMOND E. GRABER, retired, served as a plant ecologist with the Northeastern 

Station at Durham, New Hampshire. He graduated in forest management from the 

University of Washington and has studied forest ecology at Oregon State University 

and botany at the University of New Hampshire. 

Manuscript received for publication 12 May 1993 

Northeastern Forest Experiment Station 

5 Radnor Corporate Center 

100 Matsonford Road, Suite 200 

Radnor, Pennsylvania 19087-4585 

I 

August 1993 
American beech (Fagus grandifolia Ehrh.) is a common 

species in New Hampshire, comprising about 5 percent of 

the total cubic volume and 11 percent of the volume in the 

northern hardwood (beech-birch-maple) type. An excellent 

fuelwood and pulpwood species and of moderate value for 

sawtimber, beech is highly regarded as a producer of hard 

mast for wildlife. More than 20 species of vertebrates in 

New Hampshire commonly eat beechnuts, which account 

for more than 2 percent of the diet of 12 of these species 

(Martin et al. 1951). 

Studies in the Lake States have documented some aspects 

of beechnut producfion and losses over a 10-year period 

(Gysel 1971), but little information is available for New 

England except from one old-growth stand (Graber and 

Leak 1992). The purpose of this paper is to summarize 

beechnut production and losses over a 6-year period from 

41 stands in the White Mountains of New Hampshire, and to 

relate beechnut crops to stand characteristics. This is part 

of an overall study of seed production from northern 

hardwood stands initiated in 1971 by Graber. 

The male and female flowers of beech bloom in late May in 

the study area after the leaves unfold, and are borne 

separately on the same tree (monoecious). The flowers are 

considered susceptible to late spring frosts. The fruit, 

consisting of two or three angular nuts within a prickly husk, 

ripens in the fall. After maturity, the husk opens, allowing 

the nuts to fall (Schopmeyer 1974). Dispersal is chiefly by 

gravity and small mammals; however, more recent evidence 

indicates that blue jays may transport large quantities of 

beechnuts several miles and bury them in the ground 

(Johnson and Adkisson 1985). 

Met hods 

Fifty-five plots were established in evenaged, well-stocked 

(no evidence of cutting) northern hardwood stands in the 

southeastern portion of the White Mountain National Forest. 

Each plot was a uniform 1 hectare in size located within a 

larger uniform stand. Forty-one of these plots contained 

sufficient beech to be used in this analysis. Stand age 

ranged from 10 to 140 years, and the proportion of beech 

(based on percentage of basal area) ranged from 3 to 70 

percent. 

Seedfall was measured during the snowfree season using 

20 systematically located seed traps per plot. Each trap was 

a metal cylinder 15.3 cm in diameter and 17.7 cm tall with a 

metal-screen wind deflector, hardware-cloth cover to 

eliminate animal depredation, and a cloth bag liner. During 

winter, the number of seed traps was reduced to 10, and 

each trap was filled with antifreeze and raised above the 

maxi~num snowpack (see Graber and Leak 1992). Seeds 

were collected at 2-week intervals during the snowfree 

season and at 6- to 8-week intervals during winter. Seedfall 

measurements were taken from 1976 through 1980 on most 

plots, and through 1981 on about half of the plots. 

Viability was estimated in the laboratory by cutting tests to 

determine whether seeds were filled (60 percent or more) or 

empty. The type of damage (insect, rodent, bird) also was 

detected and recorded. 

The following seed classification was used in this study: 

Filled Seed-More than 60 percent of the seed cavity is 

filled. Endosperm is creamy white and firm. The embryo 

is visible and well developed. 

Insect Damage-A small hole through the seed coat 

usually is visible. Sometimes a seed is empty and insect 

frass is noted. 

Rodent damage-Seeds are opened and tooth marks are 

visible. Seed contents usually are consumed. 

Bird Damage-Seeds usually are split open lengthwise; 

no teeth marks are visible. Part or all of the seed (except 

the seed coat) is eaten. 

The assumption was made that damaged seeds had been 

filled prior to predation, so the damaged seeds were 

included with the filled ones. Thus, the study provided 

estimates of the quantities of nuts that were either damaged 

or opened and consumed in the trees. Nuts that were 

removed intact from the trees, by blue jays, for example, 

were missed by the study. Losses of nuts after they reached 

the ground were not estimated. 

Results 

To evaluate the influence of stand age or stand size on 

annual seed production, average annual beechnut catch per 

acre over the 5- or 6-year period was plotted over stand 

age, average diameter of dominant trees, and percentage of 

basal area composed of beech (Fig. 1). All of these 

relationships were clearly positive. Seed production was 

noticeably higher in stands more than 50 years old or with 

dominants more than 8'inches d.b.h. The best regression 

equations predicting these relationships were: 

total seedfalllacre = -25601 + 9.6(age2) + 98.3(percent2) 

Adjusted R2 = .760 

total seedfalllacre = -41910 +798.2(dbh2) + 94.9(percent2) 

Adjusted R2 = .792 

The same approach was followed for filled seed (including 

the damaged seed) with similar results (Fig. 2). The comparable 

regression equations were: 

fitled seedlacre = -19994 + 7.4(age2) + 79.5(percent2) 

Adjusted R* = .753 

filled seedlacre = -35941 + 667.6(dbh2) + 74.7(percent2) 

Adjusted R2 = .801 

The regressions for total and filled seedlacre based on d.b.h. 

and percentage of beech are shown in Figure 3. 
5 10 15 

D.b.h. (inches) 

a 

0. . am. . a .am.*. . .H. . m1 0 am. . a. . 

20 40 60 € 

Percent 

Figure 1 .-Scatter diagrams of average annual seedtallper acre (all seed) plow over 

stand age, average d.b.h. of dominant trees, and percentage of basal area in beech. 
D.b.h. (inches) 

40 

Percent 

Figure 2.-Scatter diagrams of average annual seedfall per acre (filled seed including 

seed damage by insects, rodents, or birds) plotted over stand age, average d.b.h of 

dominant trees, and percentage of basal area in beech. 
- All Seed 

- - - Filled Seed 

40% Beech 

D.b.h. (inches) 

Figure 3.-Predicted average annual seefall (all seed and flHed) by d.b.h of dominants and parcentage 

of basal area in beach. 
The relationships between stand age or d.b.h and percent 

losses of seed due to insects, rodents, and birds also were 

examined but no trends were evident. 

Based on stands with dominants averaging 8 inches d.b.h. 

or larger, average annual seed production ranged from 

about 18,000 to more than 400,000 per acre (Table 1). Two 

years were poor seed years (1977 and 1979) that produced 

fewer than 100,000 nuts per acre. Two were medium (1976 

and 1980), with seed production of about 200,000 to 

250,000 nuts. Two years were good, i.e., more than 400,000 

nuts were produced. The proportion of good years (1:3) is 

slightly better than experienced in a single old-growth stand 

in New Hampshire (Graber and Leak 1992), which had 2 or 

3 good years in 11. 

Results from southern Michigan showed about 3 good years 

in 10 based on total seed production, but only 1 good year 

based on the yield of sound, undamaged nuts (Gysel 1971). 

However, previous work indicates that good or poor seed 

years for beech do not coincide throughout the species' 

range (Stalter 1982). The southern Michigan study in which 

seedfall was measured from selected individual trees 

suggests that beechnut production could reach 2 112 million 

per acre in the best year. So it is possible that our New 

Hampshire stands could attain higher production rates than 

reported here. 

The percentage of filled seed was fairly constant among 

years, ranging from 73 to 87. The percentage of the filled 

seed damaged by insects, rodents, and birds ranged from 

24 to 100. Insect losses were by far the greatest source of 

damage. However, after seedfall it is almost certain that 

losses to rodents and other animals are extremely high. 

Most of the remaining filted seed probably is damaged. 

Percentage losses tended to be highest during poor seed 

years, but even good crops suffered losses exceeding 70 

percent. 

For all years combined, bimonthly seedfall occurred in two 

peaks (Fig. 4). The first peak, in late June and early July, 

consisted almost entirely of insect-damaged seed. The later 

peak occurred in the latter half of September and in 

October. During the period beginning September 1, only 40 

percent of the seedfall (before reaching the ground) was 

damaged by insects, rodents, or birds. . 

Table 1.-Average seed production per acre and losses by year for stands with 

dominant trees 8 inches d.b.h. and larger 

No. of 

Year lots 

Losses of filled seed to: 

All seed 

Number 

249,147 

17,777 

401,617 

93,737 

200,182 

435,659 

SE Filled seed 

Percent 

22 77 

34 74 

21 79 

26 87 

21 75 

28 88 

Insects Rodents Birds - 

---- Percent - - - - 

16 5 3 

100 0 - 0 

44 3 2 

81 8. 1 

68 9 11 

63 4 5 
Conclusion 

All Seed 

---,Filled Seed 

O June ' July ' August ' September ' October ' November ' December I 

Figure 4.-Percentage of average annual total seedtall (all seed and filled) occurring 

semimonthly. 

This study of beechnut production and losses in the 

southeastern portion of the White Mountain National Forest 

indicated that significant seed production did not occur until 

stands were about 50 years old or dominant trees were 8 

inches d.b.h. or larger. Production of seed, total and filled, 

increased consistently with stand agelsize and percentage 

of beech. Predicted seed production for stands with 16-inch 

dominant trees and 70 percent beech is about 600,000 nuts 

per acre and 500,000 filled seed. However, only about 65 

percent of the seed falls after September 1 (when it is 

physiologically ripe), and about 40 percent of this autumn 

seedfall is damaged by insects, rodents, and birds before it 

reaches the ground. No doubt, additional heavy predation 

by rodents occurs on the ground. Heavy seed production 

occurs about one year in three, and the proportion of filled 

seed remains about constant each year between 70 to 90 

percent. 

Acknowledgment 

We appreciate the contributions of Donald F. Thompson, 

retired forestry technician. Don's dedicated efforts on the 

collection, evaluation, and recording of seed data were 

essential to the successful completion of this study. 

Literature Cited 

Graber, Raymond E.; Leak, William B. 1992. Seed fall in an 

old-growth northern hardwood forest. Res. Pap. 

NE-663. Radnor, PA: US. Department of Agriculture, 

Forest Service, Northeastern Forest Experiment Station. 

11 p. 

Gysel, L.W. 1971. A 10-year analysis of beechnut 

production and use in Michigan. Journal of Wildlife 

Management. 35: 51 6-519. 

Johnson, W.C.; Adkisson, C.S. 1985. Dispersal of beech 

nuts by bluejays in fragmented landscapes. American 

Midland Naturalist. 113: 319-324. 

Martin, A.C.; Zim, H.S.; Nelson, A.L. 1951. American 

wildlife and plants. New York: McGraw-Hill. 500 p. 

Schopmeyer, C.S., tech. ed. 1974. Seeds of woody plants 

in the United States. Agric. Handb. 450. Washington, 

DC: U.S. Department of Agriculture. 883 p. 

Stalter, R. 1982. Production of viable seed by the 

American beech (Fagus grandifolia)). Bulletin of the 

Torrey Botanical Club. 109: 542-544. 
Leak, William B.; Graber, Raymond E. 1993. Six-year beechnut 

production in New Hampshire. Res. Pap. NE-677. Radnor, PA: US. 

Department of Agriculture, Forest Service, Northeastern Forest 

Experiment Station. 6 p. 

Beechnut production and losses were studied over a 6-year period in 41 

northern hardwood stands ranging in age from 10 to 140 years in the White 

Mountains of New Hampshire. Beechnut production increased consistently 

with stand age or d.b.h. of dominant trees and percentage of basal area 

composed of beech. Losses to insects, rodents, and birds before the seed 

reached the ground ranged from 24 to 100 percent; insects caused the 

greatest losses. Good seed years occurred about every third year. 

Keywords: American beech; mast; seedfall; seed production 

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