4Gii3*5 United States [e): Department of 

B,s? Agriculture Residual Stocking not Seriously 

Forest Service Reduced by Logging Damage 

~~~th~~~t~~~ Experiment Station ~~~~~t from Thinning of West Virginia 

Research 

Paper N E-541 

Cherry-Maple Stands 

1984 Neil I. Lamson *$i" 5'- @ %I& , H. Clay Smith 

Gary W. Miller 
Abstract 

In north-central West Virginia, unmanaged 60-year-old cherry-maple 

stands were thinned to 75,60, and 45 percent residual stocking. Cut trees were 

skidded tree length by a ru bber-tired skidder. Logging destroyed or severely 

bent over 22, 23, and 45 percent of the unmarked stems in the 75, 60, and 45 

percent stocked plots. Because 99 percent of the destroyed and bent trees 

were less than 5.0 inches dbh, the effect on basal area and residual stocking 

was slight. Damage reduced the stocking by 5, 8, and 8 percent in the 75, 60, 

and 45 percent plots. For the 75,60, and 45 percent plots, 18,38, and 42 percent 

of the residual stems received wounds that exposed sapwood. Study results 

indicate that marking guidelines for trees larger than 5.0 inches dbh do not 

need to be adjusted to account for logging damage. 

The Authors 

Neil I. Lamson received his B.S. and M.S. in silviculture and forest soils 

from the State University of New York College of Environmental Science and 

Forestry. He joined the Forest Service, State and Private Forestry, in 1972. 

Currently he is a research forester in timber management at the Northeastern 

Forest Experiment Station's Timber and Watershed Laboratory in Parsons, 

West Virginia. 

H. Clay Smith is project leader in timber management research at the 

Northeastern Forest Experiment Station's laboratory at Parsons, West 

Virginia. He received a B.S. degree from West Virginia University and a M.S. 

degree from Purdue University. He has been working for the U.S. Forest Service 

since 1962. 

Gary W. Miller, economist, attended the University of Pittsburgh and 

West Virginia University, where he received a B.S.F. and M.S.F. in forest 

resources management. Since 1981, he has conducted research in timber 

management at the Timber and Watershed Laboratory in Parsons, West 

Virginia. 

Manuscript received for 

publication 17 October 1983 
Introduction Data 

Each time the forest is cut, some 

residual trees are damaged. Damage 

may include complete destruction of 

a potential crop tree, broken branches, 

or exposed sapwood. An important 

question in thinning even-aged stands 

is: Should an allowance be made in 

marking for logging damage to residual stems? This paper reports on 

damage to residual trees resulting 

from thinning even-aged cherry-maple 

(Prunus serofina Ehrh.-Acer rubrum L.) 

stands in West Virginia to three levels 

of residual stocking with a rubbertired skidder. 

The Study Area 

The study area is located on 

Middle Mountain in the Monongahela 

National Forest in north central West 

Virginia. Treated stands were previously unmanaged even-aged cherrymaple stands about 60 years old. In 

trees at least 7.0 inch in dbh, the 

stands averaged 881 trees per acre, 

with a basal area of 165 ft2 per acre, a 

cubic foot volume of 2,854 ft3 per acre 

for trees at least 5.0 inches in dbh, 

and a board foot volume (International) 

of 7,314 fbm per acre for trees at least 

11.0 inches in dbh. The study area is 

representative of about 125,000 acres 

of commercial forest land in the area 

and resembles the Allegheny hardwood forests of northwestern Pennsylvania. The terrain of the study area 

was nearly flat. 

As part of a large study to test 

the applicability of the Allegheny 

hardwoods stocking guide (Roach 

1977) in this region, 2-acre plots were 

thinned to 75, 60, and 45 percent 

residual stocking. Twelve plots, 4 

thinned to each level, were included 

in this portion of the study. Within 

each 2-acre plot, an observation plot 

of '/2 acre was installed. After the 

2-acre plots were marked for thinning, 

all residual trees at least 1.0 inch in 

dbh on the observation plots were 

permanently identified. Each tree was 

carefully examined for wounds resulting from natural causes before logging. Species, diameter, and crown 

class of each residual tree were also 

recorded before logging. 

The plots were logged by a threeman crew using chain saws and a 

rubber-tired skidder. One man felled 

and topped trees to a 6-inch dib while 

the other two skidded tree-length logs 

to the decking area. Trees 3.6 inches 

dbh and larger were marked; however, 

those less than 7.0 inches dbh were 

cut but not skidded from the plots. Up 

to nine chokers were used per hitch 

with the skidder permitted to run 

throughout the plot. Trees from one 

2-acre plot were not skidded through 

other plots. Felling and skidding 

started at the back of each plot and 

proceeded toward the main skid road 

or deck. Trees were directionally 

felled whenever possible, although 

the dense stands and level terrain 

made it impossible to fell all of the 

trees directionally. 
Results 

All logging operations were done 

in the spring of the year when the bark 

was slipping and logging damage to 

residual trees could be expected to be 

greatest. After logging, each residual 

tree on the observation plots was 

carefully examined for logging injuries. Four types of injuries were 

noted: 1) completely destroyed (Figures 1, 2, and 3); 2) bent over or severely leaning; 3) exposed sapwood; 

4) broken tops. The length and width 

of each wound that exposed~apwood 

were measured. 

Two types of damage, destroyed 

trees and bent or severely leaning 

trees, reduced the number of residual 

trees and lowered the residual stand 

stocking below the desired level. In 

the following discussions, these types 

of damage are expressed as a percentage of the unmarked portion of 

the stand. Conversely, damage involving exposed sapwood and broken tops 

affected only the quality of the residual trees and did not affect stand 

stocking. These types of damage are 

expressed as a percentage of the net 

residual stand-the unmarked stand 

minus destroyed and bent or severely 

leaning stems. 

Figure 1.- 

skidding. 

,Saplings destroyed during 
Figure 2.-Saplings bent over 

during skidding. 

Figure 3.- Exposed sapwood wound. 
Destroyed 

For the 75,60, and 45 percent 

residual stocking plots, 11,22, and 30 

percent of the unmarked trees were 

destroyed by logging. Because most 

of the destroyed trees (99 percent) 

were less than 5.0 inches dbh, residual basal area was not seriously 

reduced. Only 2, 4, and 5 percent of 

the unmarked basal area was destroyed by logging in the 75, 60, and 

45 percent stocked plots (Tables 1, 2, 

3), resulting in plots with an actual 

stocking of 69, 53, and 37 percent 

after logging. 

Bent Over or Leaning 

For the 75, 60, and 45 percent 

stocking levels, a total of 72, 64, and 

70 stems per acre were bent over or 

left leaning by logging. Ninety-nine 

percent of these trees were less than 

5.0 inches dbh. This form of damage 

amounted to 12 percent of the unmarked stems and about 2 percent of 

the unmarked basal area (Tables 1,2, 

and 3). Although these injuries did not 

kill the trees, such trees often die 

soon from snow and ice damage. 

Exposed Sapwood 

In the plots with 75 percent residual stocking, 18 percent of the 

residual stems comprising 25 percent 

of the residual basal area had damage 

that exposed sapwood (Table 1). In 

the plots with 60 percent residual 

stocking, 38 percent of the residual 

stems comprising 43 percent of the 

residual basal area had exposed sapwood (Table 2). Sapwood damage was 

most severe in the 45-percent-residualstocking plots. Forty-two percent of 

the residual stems comprising 56 

percent of the basal area had exposed 

sapwood in the heavy thinning treatment (Table3). Thus, there was a direct 

relation between exposed sapwood 

and intensity of thinning: as the number of stems and basal area removed 

increased, sapwood was exposed on 

more trees. 
Table 2.-Summary of logging damage in plots thinned to 60 percent residual s

Stems per acre, by dbh class - - - -- - -- -- - - - - pp 

Basal area per acre (ft2), by dbh 

1 .O-4.9 in 5.0-10.9 in 1l+ in Total 1.0-4.9 in 5.0-10.9 in 11+ 

Initial stand 

Marked cut 

Unmarked standa 

Bent over or leaning 

Destroyed 

Net residual standb 

Exposed sapwood 

Broken top 

aunmarked stand = initial stand - marked cut. 

bNet residual stand = unmarked stand - (destroyed + bent over or leaning). 

Table 3.-Summary of logging damage in plots thinned to 45 percent residual s

-- -- - - - - -- ----a 

Stems per acre, by dbh class Basal area per acre (ft2), by db

-- - ---- - - -- - - 

1 .O-4.9 in 5.0-1 0.9 in 1l+ in Total 1 .O-4.9 in 5.0-10.9 in 11+ 

-- - - - -- - - - - - - --- -- 

Initial stand 489 275 63 826 19.5 93.0 53

Marked cut 106 229 22 - - 357 

-- 10.2 72.3 17

- - --- 

Unmarked standa 383 46 4 1 469 9.3 20.7 36

Bent over or leaning 69 

Destroyed 140 

-- 

Net residual standb 174 

Exposed sapwood 61 2 1 27 109 1.9 10.0 22

Broken top 21 1 1 23 0.5 0.4 1

- - - - -- - - - 

&Unmarked stand =z initial stand - marked cut. 

bNet residual stand = unmarked stand - (destroyed + bent over or leaning). 
An important factor in sapwood 

damage is the size of the wounded 

tree, ln I-his study, the percentage 

of residual trees with exposed sapwood increased with heavier thinning. 

The distribution of sapwood damage 

among size classes, however, remained about the same in each treatment. About 55 percent of the wounded 

trees were less than 5.0 inches dbh 

and 83 percent were less than 11 -8 

inches dbh. 

Broken lops 

A few residual trees suffered 

broken tops during logging ("Tbles 1, 

2, and 3). The most damage occurred 

in the heavily thinned plots (45 percent residual stocking), where 9 percent of the residual trees sustained 

broken tops. In the plots with 60 percent and 75 percent residual stocking, 

10 percent and 3 percent of residual 

trees, respectively, sustained broken 

tops. Nearly all trees (96 percenQ with 

this type of injury were less than 5.0 

inches dbh, so a very small portion of 

the residual basal area was affected 

by top damage. 

Effect on Residual 

Stand Stocking 

The stands were marked according to the Allegheny hardwoods 

stocking guide (Roach 1977) with no 

allowance for logging damage to the 

residual stand. Trees that were bent 

over were included with destroyed 

trees in calculating the stocking of 

the residual stand (Tables 1,2, and 3). 

Residual stand stocking was reduced 

5,8, and 8 percent by logging damage 

in the 75, 60, and 45 percent residual 

stocking areas, respectively (Tables 

1, 2, and 3). About 99 percent of the 

destroyed or bent over trees were less 

than 5.0 inches dbh. 

The results of this study are 

about the same as those of other 

studies of logging damage in upland 

hardwood even-aged and uneven-aged 

sbndds. In partial cuts made with a 

rubber-tired skidder or crawler tractor 

with a rubber-tired arch skidding treelength logs, seriously injured or destroyed trees amounted to less than 

10 percent of the residual basal area 

in the stand. This damage was concentrated in the sapling size class 

fVVeitzman and Holc~mb 1952, Herrick 

and Deitschman 1956; Nyland and 

Gabriel 1972). 

The thinning treatment currently 

recommended1 for these stands is to 

reduce the residual stand stocking 

to abou"i0 percent. In stands with 20 

or more square feet of basal area in 

trees 1 to 5 inches dbh, it is further 

recommended that sapling basai area 

be reduced to less than 10 ft2 per acre. 

If thinned to 60 percent residual stocking, about 35 to 40 percent of the 

residual stems will receive injuries 

that result in exposed sapwood. Over 

half of the wounded trees will be less 

than 5.0 inches in dbh. 

'Allegheny hardwoods silviculture 

training course. Northeastern Forest Experiment Station, Forestry Sciences 

Laboratory, Warren, PA. 

Size of exposed sapwood wounds 

is an important factor, Research has 

shown that wounds with over 100 in2 

of exposed sapwood are likely to develop decay (Hesterberg 1957; Lavallee 

and Lortie 1968). Lamson and Miller 

(1983) found that in these same stands 

logged with the wheeled skidder, 

about 7, 13, and 22 percent of the 

residual dominant and codominant 

stems had exposed sapwood wounds 

of at least 100 in2 in plots with 75, 60, 

and 45 percent residual stocking, 

respectively. In other words, it appears 

that most of the sapwood wounds on 

potential crop trees are small enough 

to heal with little danger of sapwood 

decay. Also, many of the trees with 

large sapwood wounds can be removed in future thinnings. 

When trees bent over or leaning 

are combined with destroyed trees in 

the plots with 60 percent residual 

stocking, the total damage accounts 

for only about 6 percent of the basai 

area. Residual stand stocking was 

reduced 8 percent by this type of 

damage. Because most of the losses 

occurred in trees less than 5.0 inches 

in dbh, competition for light among 

dominant, codominant, and intermediate trees was not influenced by 

logging damage. 
Conclusions Literature Cited 

From this study, the following 

conclusions can be stated about thinning 60-year-old cherry-maple stands 

in northern West Virginia. 

1. At three thinning levels, providing 

75, 60, and 45 percent residual 

stocking, logging damage was 

concentrated in trees less than 5.0 

inches dbh. 

2. At 60 percent residual stocking: 

a. Logging injuries that result in 

exposed sapwood were found 

on 38 percent of the residual 

trees and about 88 percent of 

these injured trees were less 

than 11.0 inches dbh. 

b. Logging damage that resulted 

in destroyed or bent over trees 

reduced the stocking only about 

8 percent. 

Recommendations 

1. In stands with less than 20 ft2 of 

basal area per acre in trees less 

than 5.0 inches dbh, marking guidelines do not need to be adjusted to 

account for logging damage. 

2. In stands with more than 20 ft2 of 

basal area per acre in trees less 

than 5.0 inches dbh, reduce the 

marked cut in saplings by 5 to 10 

stocking percentage points to account for logging damage. 

3. Marking guidelines for trees over 

5.0 inches dbh do not need to be 

adjusted to account for logging 

damage. 

Herrick, David E.; Deitschman, Glenn H. 

Effect of tractor togging upon hardwood stands. For. Prod. J. 9(10): 

403-408; 1956. 

Hesterberg, 6. A. Deterioration of 

sugar maple following logging 

damage. Stn. Pap. 51. St. Paul, MN: 

U.S. Department of Agriculture, 

Forest Service, Lake States Forest 

Experiment Station; 1957. 58 p. 

Lamson, Neil I.; Miller, Gary W. Logging damage to dominant and co. 

dominant residual stems in thinned 

West Virginia cherry-maple stands. 

In: Proceedings 4th Central Hardwoods Conference; 1982 Nov. 9-10; 

Lexington, KY. Lexington, KY: University of Kentucky; 1983: 32-38. 

Lavallee, A.; Lortie, M. Relationships 

between external features and trunk 

rot in living yellow birch. For. Chron. 

44(2):5-10; 1968. 

Nyland, Ralph D.; Gabriel, William J. 

Injuries from tree-length skidding 

with rubbermtired vs. crawler tractors. AFRI Res. Rep. 8. Syracuse, 

NY: State University of New York, 

College of Forestry, Syracuse University; 1972. 1 1 p. 

Roach, Benjamin A. A stocking guide 

for Allegheny hardwoods and its 

use in controlling intermediate cuttings. Res. Pap. NE-373. Broomall, 

PA: United States Department of 

Agriculture, Forest Service, Northeastern Forest Experiment Station; 

1977. 30 p. 

Weitzman, Sidney; Holcomb, Carl J. 

How many trees are destroyed in 

logging? Stn. Note 17. Upper Darby, 

PA: U.S. Department of Agriculture, 

Forest Service, Northeastern Forest Experiment Station; 1952. 4 p. 
Lamson, Neil I.; Smith, H. Clay; Miller, Gary W. Residual stocking 

not seriously reduced by logging damage from thinning of West 

Virginia cherry-maple stands. Res. Pap. NE-541. Broomall, PA: 

U.S. Department of Agriculture, Forest Service, Northeastern 

Forest Experiment Station; 1984. 7 p. 

In north-central West Virginia, unmanaged 60-year-old cherrymaple stands were thinned to 75, 60, and 45 percent residual 

stocking. Cut trees were skidded tree length by a rubber-tired 

skidder. Logging destroyed or severely bent over 22, 23, and 45 

percent of the unmarked stems in the 75, 60, and 45 percent 

stocked plots. Because 99 percent of the destroyed and bent 

trees were less than 5.0 inches dbh, the effect on basal area and 

residual stocking was slight. Damage reduced the stocking by 

5,8, and 8 percent in the 75,60, and 45 percent plots. For the 75, 

60, and 45 percent plots, 18, 38, and 42 percent of the residual 

stems received wounds that exposed sapwood. Study results 

indicate that marking guidelines for trees larger than 5.0 inches 

dbh do not need to be adjusted to account for logging damage. 

ODC 242:461:535: 176.1 

Keywords: Logging damage; thinning; stocking 

-, U S GOVERNMENT PRINTING OFFICE: 1984-705-0291506 
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. 

0 Berea, Kentucky, in cooperation with Berea College. 

0 Burlington, Vermont, in cooperation with the University of 

Vermont. 

Delaware, Ohio. 

Durham, New Hampshire, in cooperatian with the University of 

New Hampshire. 

0 Hamden, Connecticut, in cooperation with Yale University. 

Morgantown, West Virginia, in cooperation with West Virginia 

University, Morgantown. 

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

Orono. 

0 Parsons, West Virginia. 

@ Princeton, West Virginia. 

0 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.