,*i+ United States 

Department of 

Agriculture Costs of Reducing Sapling Basal 

Forest Service Area in Thinned Cherry-Maple 

No,heasternForest Stands in West Virginia Experiment Station 

Research 

Paper N E-540 

1984 Gary W. Miller 
The Author 

Gary W. Miller is an economist 

for the timber management research 

project at the Timber and Watershed 

Laboratory, Northeastern Forest Experiment Station, Parsons, West 

Virginia. 

Manuscript received for 

publication 16 November 1983 

Abstract 

Unmanaged 60-year-old cherrymaple stands in West Virginia were 

thinned to three levels of stocking 

according to the A1 leg heny hardwoods 

stocking guide. After the merchantable 

timber was removed, the basal area in 

saplings was reduced to less than 

10 ft2&per acre (2.3 m21ha), as the guide 

recommends for stands with dense 

understories. A detailed time study 

revealed that cutting saplings with 

chain saws costs about $1 7.00 per 

acre ($42fha). This amount may be 

recoverable in increased yield, tax 

deductions, and fuelwood sales. 

Cover Photo 

Saplings were felled by experienced loggers. 
Introduction The Study Area 

The stocking guide for Allegheny 

hardwoods recommends thinning evenaged stands to 60 percent of full stocking, the minimum stocking theoretically needed to utilize the site fully 

(Roach 1977). Other stocking guides 

developed for eastern forest types 

have similar residual stocking recommendations, but none of the guides, 

including the guide for Allegheny 

hardwoods, support their recommendations with actual response data 

(Leak 1981). As part of a large thinning 

study designed to test and refine the 

Allegheny hardwoods stocking guide 

for use in West Virginia, the implications of reducing sapling basal area 

as recommended by the guide were 

examined. 

In addition to providing general 

guidelines on residual stand density, 

the Allegheny guide makes specific 

recommendations for distributing the 

cut among species groups and size 

classes, including saplings, defined 

as stems 1.0 to 5.5 inches (2.5-14.0 

cm) dbh. Of particular concern from 

an economic standpoint is the recommendation to greatly reduce sapling 

basal area in stands with relatively 

dense understories. The economic 

impact of sapling removal depends 

on the cost of the treatment and the 

response of the residual trees in the 

stand. Net revenues from commercial 

thinnings can be quickly eroded by 

operations in the nonmerchantable 

portion of the stand. Without sufficient increases in the growth of residual trees, sapling removal will not 

only reduce net revenues of commercial thinning, but will also reduce net 

present value of timber production on 

the area. 

Some recent studies have shown 

that reducing understory basal area 

in thinned hardwood stands increases 

the growth of residual trees in the 

overstory. Dale (1975) found that 

thinned upland oak stands with all 

woody stems less than 1.6 inches 

(4.1 cm) dbh eradicated grew faster 

than stands similarly thinned but 

with the understory left in place over 

a 10-year period. Karnig and Stout 

(1969) found that understory removal 

after a heavy thinning resulted in a 

slight increase in basal area growth 

of red oak over three growing seasons. 

Although these studies showed that 

understory removal in conjunction 

with thinning increases the growth of 

residual trees, cost and return data 

were not available to evaluate its eeonomic feasibility. 

This report provides cost indicators and discusses the economic 

and silvicultural implications of sapling removal as a separate stand 

treatment following commercial logging. Data were collected in cherrymaple (Prunus serotina Ehrh.-Acer 

rubrum L.) stands in West Virginia, 

but the information can be helpful 

wherever stocking guides are used to 

control intermediate cuttings in hardwood stands. 

The study was conducted in 

the Middle Mountain area of the Monongahela National Forest. Treated 

stands were previously unmanaged 

even-aged black cherry-maple stands 

about 60 years old. The study area is 

representative of about 125,000 acres 

(50,600 ha) of commercial forests in 

north central West Virginia and resembles the Allegheny hardwood forests of northwestern Pennsylvania: 

rainfall averages about 55 to 60 inches 

(1.4-1.5 m) per year; site index for 

black cherry is 75 feet (23 m). The 

terrain in the immediate study area is 

gentle rolling hills with slopes generally less than 10 percent. 

The overstory was primarily black 

cherry and red maple with some white 

ash (F raxinus americana L.). The 

understory was made up of American 

beech ( F agus grandifolia E hrh.), red 

maple, and sugar maple (Acer saccharum Marsh.). Based on a complete 

inventory of all trees 1.0 inch (2.5 cm) 

dbh and larger on eighteen '/z-acre 

(0.2 ha) plots, the average basal area 

was 164 ft2 per acre (38 m21ha) with 

69 percent of the basal area in the 

cherry, ash, yellow-poplar (Liriodendron tulipifera L.) (CAPS) species 

group. Basal area ir: saplings averaged 25 ft2 per acre (5.7 m21ha). The 

study area also averaged 826 trees 

per acre with an average diameter of 

6.0 inches (15.2 cm). According to the 

stocking chart (Roach 1977), the area 

was about 110 percent stocked before 

thinning. 

In merchantable trees 7.0 inches 

(1 7.8 cm) dbh and larger, the study 

area averaged 216 trees per acre 

(5341ha) with an average diameter of 

10.4 inches (26.4 cm) dbh. 
Plot Treatments Data Collection 

Eighteen 2-acre (0.8 hectare) experimental units were randomly divided among three thinning densities, 

75,60, and 45 percent of full stocking. 

Each 2-acre unit was marked as recommended in the Allegheny hardwoods stocking guide (Roach 1977). 

For example, two-thirds of the basal 

area cut was below the average diameter in each species group (CAPS and 

others). Saplings as well as poles and 

sawtimber were marked. Although 

marking in the poles and sawtimber 

varied with the target density, the 

marked cut for saplings was essentially the same for all thinning densities, averaging 16 ft2 of basal area per 

acre (3.7 m21ha) in the 18 plots. 

Calculations were based on a 

complete inventory of all trees 1.0 

inch dbh (2.5 cm) and larger on a 

I/2-acre (0.2 hectare) measurement 

plot located within each 2-acre unit. 

Trees not marked for cutting in the 

%-acre measurement plot were tagged 

for long-term study. 

Six 2-acre units, two from each 

thinning density, were logged in the 

fall of 1981. All marked trees 7.0 

inches dbh (17.8 cm) and larger were 

cut and skidded. No trees smaller 

than 7.0 inches dbh were cut in these 

six units. 

Twelve 2-acre units, four from 

each thinning density, were logged in 

the spring of 1982. After all marked 

trees 7.0 inches dbh and larger had 

been removed, marked trees smaller 

than 7.0 inches dbh were cut. These 

included marked saplings and marked 

nonmerchantable poles 5.6 to 6.9 

inches (14.2-17.5 cm) dbh. This part 

of the thinning was carried out as a 

separate operation. 

Cost data collected from these 

I2 thinning units included fuel usage, 

machine-hours, and man-hours. On 

five plots, man-hours were measured 

by the detailed time study method. 

The activities of workers were divided 

into work cycles and the cycles were 

subdivided into cycle elements. An 

observer recorded each element as it 

occurred without missing any time 

between successive elements. 

Work cycle elements were classified as either productive elements or 

delay elements. Productive elements 

included WALK, SWAMP, and FELL. 

Delay elements included REFUEL, 

REPAIR SAW, WAIT, REST, and PERSONAL. The characteristic beginning 

and ending points of each element 

were defined to allow for consistency 

in the timing procedure. 

Gross job time and the number 

of stems cut were recorded for each 

of the twelve 2-acre units. On the five 

time-study units, gross time was determined as the sum of all cycle times 

and the number of stems cut equaled 

the number of cycles. On the other 

seven treatment units, the number of 

cut trees was estimated from inventories of the M-acre measurement 

plot within each unit. 
Results 

Cost Per Tree 

A total of 632 trees were felled 

during the detailed time study. Productive time plus delay time totaled 

about 430 minutes of work. The bulk 

of productive time was spent walking 

from tree to tree, while swamping 

time was nearly negligible (Table 1). 

Delays amounted to 38 percent of the 

total job time, and half of the delay 

time was spent refueling, repairing, 

and servicing the chain saws. Another 

35 percent of the delay time was 

spent resting. 

The average time required to cut 

saplings under the conditions studied 

was 0.68 minutes per tree, counting 

delays. Gabriel and Nissen (1974) 

obtained similar results in New York. 

However, cutting saplings and small 

poles in the 45 percent treatment 

required about 0.76 minutes per tree, 

because the abundance of slash and 

tops made walking from tree to tree 

more difficult (Table 2). The actual 

dollar cost per tree depends on the 

size of the trees included in the cut, 

the intensity of the cut, and the hourly 

cost of labor and equipment. 

Table 1.-Time in minutes for productive activities: 

cutting nonmerchantable stems after logging 

Dbh class N o. Elements 

Percent Total Percent Mean time (inches) stems Walk Swamp Fell per stem 

4 273 43 58.9 0.8 38.5 98.2 37 0.36 

5 205 32 49.4 1.3 38.7 89.4 33 0.44 

6 117 19 27.7 1.8 29.3 58.8 22 0.50 

7 - 37 - 6 8.6 1 - 

.O 11.6 21.2 - 

8 0.57 

Total 632 100 144.6 4.9 118.1 267.6 100 0.42 

Percent 54 2 44 1 00 

Table 2.-Time required to cut nonmerchantable stems 

after logging in the three thinning treatments 

Treatment: Stocking 

percent before 

stocking sapling cut 

Cut required 

to reach 

desired stocking 

Cutting time Total time 

per tree per acre 

- 

O/O Stems/acrea BA/a~re(ft~)~ min hra 

aFor stems per hectare multiply stems per acre by 2.47 

bFor m2 per hectare multiply ft2 per acre by 0.23. 
Cost Per Hour 

The machine costs presented 

here are based on a new McCulloch 

Pro Mac 8001 with a 24-inch bar. The 

fixed cost, including depreciation and 

interest, insurance, and taxes was 

$0.43 per hour (Miyata 1980). The 

operating cost was $1.51 per hour. 

The total labor cost, including a wage 

of $5.50 per hour and 28 percent mandatory fringe benefits, was $7.04 per 

hour. The hourly machine cost will 

differ for different chain saws and the 

labor cost could differ with location. 

Total cost under the conditions studied 

was $8.98 per scheduled hour of work. 

Cost Per Acre 

The cost per acre to cut saplings 

and nonmerchantable stems was 

nearly equal in the three treatments. 

In the 75 and 60 percent treatments, 

the cut required to reach the target 

level of stocking was 20 ft2 of basal 

area per acre (4.6 m21ha), roughly 150 

trees (Table 2). This required about 

1.64 hours at a cost of $14.58 per acre. 

In the heavily thinned plots, the cut 

required to reach 45 percent residual 

stocking was less, only 17 ft2 per 

acre (3.9 m21ha). Because the cutting 

time per tree was higher in the45 

percent treatment, its cost was about 

the same as the other treatments, 

$14.82 per acre. A contractor or consulting forester hired to cut nonmerchantable stems would require a 

margin of profit to complete the operation. A 15 percent margin for profit 

and risk brings the total treatment 

cost to about $1 7.00 per acre ($42.00 

per hectare). 

Silvicultural Implications 

Ignoring the saplings and other 

nonmerchantable stems when thinning hardwood stands can lead to a 

silvicultural dilemma. If the stands 

are marked according to the stocking 

guide, with nonmerchantable stems 

included in the mark but not actually 

cut, the residual stands would have a 

higher percentage stocking than desired. In plots targeted for a 60 percent thinning, residual stocking was 

76 percent before the saplings and 

nonmerchantable stems were cut 

(Table 2). At this level of stocking 

mortality begins to increase, reducing 

net growth and the rate of product 

development (Roach 1977). Growth 

is distributed among many trees, 

some of it wasted on trees that will 

die before the next cut. 

On the other hand, if desired 

stocking is achieved by heavier cutting in the merchantable size classes, 

the dominant and codominant crop 

trees will be overcut. Mortality would 

not be a problem until the stand 

reached about 80 percent stocking, 

but growth would be concentrated on 

smaller stems (Roach 1977). As a result, board foot volume production 

would be reduced and the big dollar 

yield at rotation age would be delayed. 

In stands with sparse understories, less than 20 ft2 per acre (4.6 

m21ha) in saplings, the effect of saplings in the marked cut is slight. 

However, in stands with dense understories, saplings and nonmerchantable 

poles should be included in the cut 

to achieve a balanced and effective 

thinning. 

Economic Implications 

The purpose of thinning these 

60-year-old stands was to concentrate 

growth on the best trees in the stand, 

increase yield by salvaging trees that 

would die, and reduce the time required for the stand to reach physical 

maturity. Thinning merchantable 

stems reduces overstory competition 

and leads to faster growth of residual 

crop trees. If reducing sapling basal 

area further stimulates the growth of 

residual crop trees, then cutting saplings could produce a net economic 

gain. 

For sapling cutting to be profitable, stands so treated must provide 

increased dollar yields in later thinnings and final harvest that exceed 

the cost of sapling removal. Increases 

in dollar yields, if any, will most likely 

be from improved tree quality or increased board foot yields, or both. An 

example shows that the additional 

yield required (over stands that were 

only thinned) iS not unreasonable 

(Table 3). 

The example presented deals 

with after-tax cash flows. Because 

the cost of noncommercial thinning 

in established stands may be deducted as an operating expense, the 

actual cost of sapling removal is 

determined by the landowner's marginal tax rate (U.S. Forest Service 

1982; Weston and Brigham 1981). The 

example assumes a marginal tax rate 

of 25 percent, resulting in an after-tax 

cost of $12.75 per acre ($31.491ha) for 

cutting saplings. Other assumptions 

include an average annual inflation 

rate of 5 percent and no real change 

'The use of trade, firm, or corporation 

names in this publication is for the information and convenience of the reader. 

Such use does not constitute an official 

endorsement or approval by the U.S. 

Department of Agriculture or the Forest 

Service of any product or service to the 

exclusion of others that may be suitable. 
in stumpage prices over the investment period. Three investment periods 

were considered. 

If 9 percent is the alternative 

market rate of return, the sapling 

cut must result in added revenue of 

$47.08 per acre ($1 16.291ha) from a 

final harvest 20 years after thinning. 

This means that annual growth must 

increase by about 17 bf (International %-inch rule) per acre (0.24 

m31ha), roughly 6 percent of current 

annual growth, to equal the alternative investment. 

The actual growth capabilities of 

stands treated this way are not known, 

but growth responses and quality 

changes will be monitored over the 

next 20 years. We know that saplings 

are important in determining stand 

stocking and that treatment costs do 

not require unreasonable growth increases to justify sapling removal in 

stands with dense understories. Periodic remeasurement of the residual 

trees will disclose how much of the 

treatment costs will be offset by 

increased board foot yields as the 

stand nears final harvest. 

The cost of cutting nonmerchantable stems can be reduced by 

selling some of the material as fuelwood. The average volume available 

for sale as fuelwood from the 12 

treated plots was about 8 cords per 

acre (6.2 m31ha). If fuelwood brought 

$2 per cord on the stump, such a sale 

could offset the cost of the treatment. 

Actual fuelwood revenues, however, 

would depend on accessibility of the 

product and local fuelwood markets. 

Table 3.-Additional dollar and board foot yields 

needed to earn selected rates of return 

from cutting saplings in stands thinned 

to 60 percent residual stocking 

10 years 20 years 30 years 

Required 

returna Value Volume Value Volume Value Volume 

yield yieldb yield yield yield yield 

Percent $/a creC b f/a creC $/acre bflacre $/acre b f/a cre 

5.25 18.76 21 3 27.60 193 40.61 174 

7.50 22.04 251 38.09 266 65.84 282 

9.00 24.50 279 47.08 329 90.48 388 

Converted to after-tax rates before computing required yields. 

bstumpage revenues were treated as capital gains to determine after-tax volume yields needed to earn 

selected rates of return. 

cFor $ per hectare multiply $ per acre by 2.47. 

For m3 per hectare multiply bf per acre by 0.014. 
Literature Cited 

Dale, Martin E. Effect of understory 

removal on growth of upland oak. 

Res. Pap. NE-321. Broomall, PA: 

U.S. Department of Agriculture, 

Forest Service, Northeastern Forest Experiment Station; 1975. 10 p. 

Gabriel, William J.; Nissen, Roger 

L., Jr. A time study of felling small 

diameter hardwood trees in New 

York State. AFRI Res. Rep. No. 24. 

Syracuse, NY: Applied Forestry 

Research Institute; 1974. 4 p. 

Karning, J. J.; Stout, B. B. Diameter 

growth of northern red oak following understory control. Black Rock 

Forest Paper 30. Cornwall, NY: 

Harvard Black Rock Forest; 1969. 

16 p. 

Leak, William B. Do stocking guides 

in the Eastern United States relate 

to stand growth? J. For. 79: 661 -664; 

1981. 

Miyata, Edwin S. Determining fixed 

and operating costs of logging 

equipment. Gen. Tech. Rep. NC-55. 

St. Paul, MN: U.S. Department of 

Agriculture, Forest Service, North 

Central Forest Experiment Station; 

1980. 16 p. 

Roach, Benjamin A. A stocking guide 

for Allegheny hardwoods and its use 

in controlling intermediate cuttings. 

Res. Pap. NE-373. Broomall, PA: 

U.S. Department of Agriculture, 

Forest Service, Northeastern Forest Experiment Station; 1977. 30 p. 

U.S. Forest Service. A guide to federal 

income tax for timber owners. Agric. 

Handb. 596. Washington, DC: U.S. 

Department of Agriculture; 1982. 

74 p. 

Weston, J. F.; Brigham, E. F. Managerial finance. 7th ed. Hinsdale, IL: 

The Dryden Press; 1981: 439-442. 
Miller, Gary W. Costs of reducing sapling basal area in thinned 

cherry-maple stands in West Virginia. Res. Pap. NE-540. 

Broomall, PA: U.S. Department of Agriculture, Forest Service, 

Northeastern Forest Experiment Station; 1984. 6 p. 

Unmanaged 60-year-old c herry-maple stands in West Virginia 

were thinned to three levels of stocking according to the Allegheny hardwoods stocking guide. After the merchantable timber 

was removed, the basal area in saplings was reduced to less 

than 10 ft2 per acre, as the guide recommends for stands with 

dense understories. A detailed time study revealed that cutting 

saplings with chain saws costs about $17.00 per acre. This 

amount may be recoverable in increased yield, tax deductions, 

and fuelwood sales. 

ODC 242:323.2:535 

Keywords: cost data, sapling removal, thinning, stocking, 

northern hardwoods 

t2 U S. GOVERNMENT PRINTING OFFICE: 1984-705-0291505 
Headquarters of the Northeastern Forest Experiment Station are in 

Broomalll, 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 Hampshire. 

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.