@ pea United States 

f Department of 

Agriculture Releasing Young Hardwood Crop 

Forest Service Trees-Use of a Chain Saw Costs 

NoheasternForest Less Than Herbicides 

Experiment Station 

Research 

Paper NE-550 Gary W. Miller 
The Author 

Gary W. Miller, economist, received a B.S.F. and M.S.F. in 

forest resources management from West Virginia University and 

attended the University of Pittsburgh. Since 1981, he has conducted research in timber management with the USDA Forest 

Service, Northeastern Forest Experiment Station, Timber and 

Watershed Laboratory, Parsons, West Virginia. 

Manuscript received for 

publication 16 April 1984. 

Abstract 

A crown-touching release of 12-year-old black cherry and 

yellow-poplar crop trees on a good site required removing an 

average of 14 trees for every crop tree. An average of 80 crop 

trees per acre was left free-to-grow with an average growing 

space of 4.7 feet on all sides of the crown. Basal spraying cost 

$0.80 per crop tree, stem injecting cost $0.61 per crop tree, and 

chain saw felling cost $0.42 per crop tree. Cost indicators for 

each release method and suggestions for cost savings are 

provided. 
Introduction 

Forest managers contemplating 

crop-tree release need to consider at 

least three factors that determine the 

effectiveness and efficiency of release treatments: First, the criteria 

for recognizing potentially responsive 

hardwood stands and individual crop 

trees within those stands; second, 

the degree of release needed to increase growth of selected trees; and 

third, the application of release-applying the desired treatment at the 

lowest possible cost. 

In support of the first factor, 

recent research indicates that Appalachian hardwood crop trees had a 

significant d.b.h. growth response to 

release when the seedling and sprout 

origin codominant trees in the stand 

were at least 25 feet tall (Lamson 

1983, Smith and Lamson 1983). Apparently, until the stand is about 

25 feet tall, codominant trees have 

not competed for crown position long 

enough to permit natural selection of 

superior trees. In shorter stands, 

crown classes are not stable, often 

resulting in crown-class regression 

and inconsistent growth responses 

following release (Trimble 1973, 1974, 

Smith 1979). 

The degree of release is also 

important. Positive results were obtained when seedling origin crop 

trees were released by cutting all. 

competing trees touching or within a 

vertical projection of the crop-tree 

crown-a crown-touching release 

(Smith and Lamson 1983). Sprout 

origin crop trees had a significant 

d.b.h. growth response when released 

to a free-to-grow position by cutting 

all but one or two stems per clump 

(Lamson 1983). Bole releases, where 

stems within a specifieddistance of 

the crop-tree bole are eliminated, do 

not always provide a complete crown 

release for some species. It is important, therefore, to concentrate on the 

crop-tree crown when applying the 

release treatment. 

This paper summarizes cost information for release. The costs of 

mechanical and chemical treatments 

for releasing crop trees in a 12-yearold Appalachian hardwood stand are 

compared. The cost information reported here was recorded during a 

crown-touching release of crop trees 

measuring 30 to 35 feet tall. 

Study Methods 

Two options exist for eliminating 

unwanted trees when releasing young 

hardwoods. Competing trees can be 

chemically treated by either stem injection or basal spraying with an appropriate herbicide, or they can be cut 

mechanically. In this study, crop trees 

were released by injecting, basal 

spraying, and chain saw felling unwanted stems to define the least-cost 

method of release. 

Cost data were collected in a 

12-year-old Appalachian hardwood 

stand that contained about 2,700 

stems per acre, totalling 77 square 

feet of basal area per acre in trees 

1.0-inch d.b.h. and larger (Fig. 1). More 

than 80 percent of the trees were less 

than 3.0-inches d.b.h. Most of the 

dominant and codominant stems were 

seedling-origin black cherry, Prunus 

serotina Ehrh., and yellow-poplar, 

Liriodendron tulipifera L. Some red 

oak, Quercus rubra L., sprout clumps 

were also present. 

Figure 1.-Crop trees were severely crowded before release. 
Results 

We selected 80 crop trees per 

acre based on the following criteria: 

Species-black cherry or yellowpoplar 

Crown class-dominant or 

codominant 

Origin-seedling preferred 

Stem form-straight stem, few 

forks 

Vigor-full, healthy crowns, no 

dead tops 

In some instances. other s~ecies 

or sprout origin trees were selected 

as crop trees because they were the 

best available tree at the desired location. Cut trees were mostly black 

cherry, sweet birch, Betula lenta L., 

and red oak sprout clumps. 

~fter crop trees were selected in 

each study area, all trees (1.0-inch 

d.b.h. and larger) whose crowns 

touched or were within a vertical projection of the crop-tree crown were 

marked with orange paint. An experienced worker then injected all marked 

trees. To make a direct cost comparison, the same worker went back into 

the plot and basal sprayed all the 

marked trees. Finally, the worker 

felled the marked trees with a chain 

saw. 

During each of the three treatments, an observer recorded the time 

required to complete the operation, 

the number of trees treated, and the 

number of injections required during 

the injection treatment. The amount 

of herbicide mix needed to complete 

each operation was recorded, as were 

delays associated with each treatment such as fill-ups and rest breaks. 

Basal spraying, stem injection, , and chain saw felling were compared 

on two separate plots within the same 

stand. The first area measured 0.25 

acres, the second 0.43 acres. Addi- I 

tional cost data on chain saw felling 

were collected on two I-acre plots in! 

stalled to study the long-term effects 

of the crown-touching release. A Ihacre measurement plot within each 

1-acre treatment area provided data 

on individual trees. 

Releasing 80 crop trees per acre 

required removing 1,082 stems per 

acre, or 14 per crop tree. Following 

treatment, crop trees were left free-togrow with an average growing space 

of 4.7 feet on all sides of the crown. A 

comparison of basal spraying, stem 

injection, and chain saw felling indicated that felling eliminated unwanted stems at the lowest costabout $0.42 per crop tree. Moreover, 

felling revealed 60 additional competing trees per acre that were not 

apparent during the basal spraying 

and injection treatments. 

Basal Spraying 

An experienced worker using a 

backpack sprayer treated 309 stems 

per hour with a 4-percent mixture of 

2,443 ester in oil. The treatment required 3.5 man-hours per acre and 18 

gallons of chemical mixture per acre 

(Table 1). The total treatment cost 

was $64.00 per acre or $0.80 per crop 

tree. 

Stem Injection 

The workers injected an average 

of 204 trees per hour in the study 

plots. This.treatment required 5.3 

man-hours per acre and 1 gallon of 

chemical solution per acre. The cost 

of the chemical, a 20 percent solution 

of glyphosate found to be effective in 

killing most hardwoods (Wendel and 

Kochenderfer 1982), was $17.00 per 

gallon (Table 1). Labor and chemicals 

combined resujted in a total treatment cost of $48.80 per acre or $0.61 

per crop tree. 

Chain Saw Felling 

The workers felled approximately 

260 stems per hour. This method of 

release required 4.1 man-hours per 

acre and 3.2 machine hours per acre. 

The total cost, including labor and 

the fixed and operating costs of a 

Pro Mac 800' chain saw, was $33.60 

per acre or about $0.42 per crop tree. 

'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. 

Table 1.-Average time, volume of chemical, and cost per crop tree 

to apply a crown-touching release in 12-year-old 

Appalachian hardwood stands 

Labora Machineb Chemical 

Treatment Total 

Time Cost Time Cost Volume Cost 

Minutes Dollars Minutes Dollars Gallons Dollars Dollars 

Basal spraying 2.6 0.28 - - 0.23 0.52C 0.80 

Stem injection 4.0 .44 - - -01 .1 7d .61 

Chain saw 

fellina 3.1 .34 2.4 0.08 - - .42 

aLabor cost: $5.00 + 31 percent fringe benefits = $6.55 per hour. 

bMachine cost: $2.12 per productive hour for chain saw, negligible for other treatments. 

CChemical cost: 4 percent mixture of 2,4-D ester in oil = $2.26 per gallon. 

dchemical cost: 20 percent solution of glyphosate = $17.00 per gallon. I 
Discussion 

The total cost of labor was 

highest for stem injection. While unwanted stems in the felling and basal 

spraying operations could be treated 

from one side, injection required the 

workers to walk around trees to properly space the injections. The added 

walking and difficulty of movement 

through the dense young stand combined to reduce productivity for 

injection. 

Treatment costs can be reduced 

by selecting fewer crop trees per acre 

and by eliminating fewer trees per 

crop tree (Table 2). More than 60 percent of the trees eliminated in accordance with the crown-touching release 

guidelines were overtopped before 

treatment. In this study, if overtopped 

trees had been ignored, the release 

would have required eliminating only 

about six trees per crop tree. Chain 

saw felling, however, would still have 

been the least-cost method. 

What about sprouts from cut 

stumps? Stump sprouts in clearcuts 

can attain a height of about 35 feet in 

10 years (Wendel 1975, Lamson 1976). 

Crop trees selected in this study averaged 34 feet at the time of treatment. 

Assuming released crop trees grow 

about 2 feet per year (Smith and 

Lamson 1983, Lamson and Smith 

1978), in 10 years the crop trees will 

be more than 50 feet tall. With crown 

closure among crop trees inhibiting 

the height growth of stump sprouts, 

crop trees should maintain a distinct 

height advantage over stump sprouts 

in stands similar to the study area. 

Another advantage to chain saw 

felling is that it assures that all unwanted trees are eliminated. As trees 

are felled in favor of a selected crop 

tree, the operator can recognize competing trees at a glance. Because the 

herbicide treatments leave competitors standing, trees can be missed or 

left alive, leaving crop trees only partially released. This problem is magnified during the growing season when 

trees are in full leaf. With chain saw 

felling, the operator simply continues 

cutting until light encircles the croptree crown, regardless of the season. 

Table 2.-Cost of selectinga and releasing various numbers of crop trees 

using three methods of release 

Crop trees Basal Stem Chain saw 

per acre spraying injection felling 

aselecting crop trees in young hardwood stands required 

about 1 hour for every 47 crop trees selected (Smith and 

Lamson 1983). 
Literature Cited 

Lamson, Neil I. Appalachian hardwood stump sprouts are potential 

sawlog crop trees. Res. Note NE229. Upper Darby, PA: U.S. Department of Agriculture, Forest Service, 

Northeastern Forest Experiment 

Station; 1976. 4 p. 

Lamson, Neil I. Precommercial thinning increases diameter growth of 

Appalachian hardwood stump 

sprouts. Southern Journal of Applied Forestry 7(2):93-97; 1983. 

Lamson, Neil I.; Smith, H. Clay. Response to crop-tree release: sugar 

maple, red oak, black cherry, and 

yellow-poplar saplings in a 9-yearold stand. Res. Pap. NE-394. 

Broomall, PA: U.S. Department of 

Agriculture, Forest Service, Northeastern Forest Experiment Station; 

1978. 8 p. 

Smith, H. Clay; Lamson, Neil I. Precommercial crop-tree release increases diameter growth of Appalachian hardwood saplings. Res. 

Pap. NE-534. Broomall, PA: U.S. 

Department of Agriculture, Forest 

Service, Northeastern Forest Experiment Station; 1983. 7 p. 

Smith, H. Clay. Release of young 

yellow-poplar and black cherry10-year results. Southern Journal 

of Applied Forestry 3(4):161-164; 

1979. 

Trimble, G. R., Jr. Response to crop 

tree release by 7-year-old stems of 

yellow-poplar and black cherry. ' 

Res. Pap. NE-253. Upper Darby, PA: 

U.S. Department of Agriculture, 

Forest Service, Northeastern 

Forest Experiment Station; 1973. 

10 p. 

Trimble, G. R., Jr. Response to crop 

tree release by 7-year-old stems 

of red maple stump sprouts and 

northern red oak advance repro. 

duction. Res. Pap. NE-303. Upper 

Darby, PA: U.S. Department of Agriculture, Forest Service, Northeastern Forest Experiment Station; 

1974. 6 p. 

Wendel, G. W. Stump sprout growth 

and quality of several Appalachian 

hardwood species after clearcutting. Res. Pap. NE-329. Upper 

Darby, PA: U.S. Department of Agriculture, Forest Service, Northeastern Forest Experiment Station; 

1975. 9 p. 

Wendel, G. W.; Kochenderfer, J. N. 

Glyphosate controls hardwoods in 

West Virginia. Res. Pap. NE-497. 

Broomall, PA: U.S. Department of 

Agriculture, Forest Service, Northeastern Forest Experiment Station; 

1982. 7 p. 
Caution 

Pesticides used improperly can be injurious to man, animals, 

and plants. Follow the directions and heed all precautions on 

the labels. 

Store pesticides in original containers under lock and key-out 

of the reach of children and animals-and away from food and 

feed. 

Apply pesticides so that they do not endanger humans, livestock, crops, beneficial insects, fish, and wildlife. Do not apply 

pesticides when there is danger of drift, when honey bees or 

other pollinating insects are visiting plants, or in ways that may 

contaminate water or leave illegal residues. 

Avoid prolonged inhalation of pesticide sprays or dusts; wear 

protective clothing and equipment if specified on the container. 

If your hands become contaminated with a pesticide, do not eat 

or drink until you have washed. In case a pesticide is swallowed 

or gets in the eyes, follow the first aid treatment given on the 

label, and get prompt medical attention. If a pesticide is spilled 

on your skin or clothing, remove clothing immediately and wash 

skin t,horoughly. 

NOTE: Some States have restrictions on the use of certain pesticides. Check your State and local regulations. Also, because 

registrations of pesticides are under constant review by the 

Environmental Protection Agency, consult your local forest 

pathologist, county agricultural agent, or State Extension 

specialist to be sure the intended use is still registered. 

&.P-Y# 

FOLLOW THE LABEL 

U.S. DEPARTMENT OF AGRICULTURE 
Miller, Gary W. Releasing young hardwood crop trees-use of 

a chain saw costs less than herbicides. Res. Pap. NE-550. 

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

Northeastern Forest Experiment Station; 1984. 5 p. 

A crown-touching release of 12-year-old black cherry and yellowpoplar crop trees on a good site required removing an average 

of 14 trees for every crop tree. An average of 80 crop trees per 

acre was left free-to-grow with an average growing space of 

4.7 feet on all sides of the crown. Basal spraying cost $0.80 per 

crop tree, stem injecting cost $0.61 per crop tree, and chain saw 

felling cost $0.42 per crop tree. Recommendations on release 

methods and suggestions for cost savings are provided. 

ODC 242, 231.324, 176.1 

Keywords: Thinning, chemical release, costs, Appalachian 

hardwoods 

Q U.S. GOVERNMENT PRINTING OFFICE: 1984-705-0291530 
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 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. 

@ University Park, Pennsylvania, in cooperation with the 

Pennsylvania State University. 

@ Warren, Pennsylvania.