@ p- United States 

Department of 

Agriculture 

Forest Service 

Northeastern Forest 

Experiment Station 

Research 

Paper NE-49 9 

- 

he Yield 

Materials 

rom Small-Diameter 

Hardwood Trees 

E. Paul Craft 
The Author 

E. Paul Craft received his B.S. 

degree in forestry from West Virginia University in 1951. From 

1951 through 1961, he managed 

logging and milling operations and 

was a field representative for 

heavy construction and industrial 

equipment manufacturers. In 1962 

he joined the staff of the Northeastern Forest Experiment Station, 

Forestry Sciences Laboratory, 

Princeton, West Virginia, where he 

has served as head of engineering 

services, equipment specialist, and 

research forester. 

Manuscript received for publication 27 April 1981 

Abstract 

From poletimber stand thinning~, 52 trees were bucked into 8- 

foot lengths, and 49 trees were 

felled and bucked into 10-foot 

lengths, The 8- and 10-foot pieces 

were sawed into pallet cants and 

side lumber suitable for pallet 

parts. The sawed yield, by tree, 

from each length category was 

compared to the predicted yield of 

the same trees if bucked into 4- 

and 6-foot bolts before sawing. 

Short-bolt processing of trees 

would have yielded 11 percent 

more than actual yields for trees 

cut into &foot sections, and 17 

percent more than. actual yields for 

trees cut into 10-foot sections. 
Introduction 

Sawable bolts and logs from 

thinned hardwood polet i m ber 

stands yield from 2,100 to 4,500 

board feet per acre of sawed products, Although thinnings yield very 

little high quality wood, virtually 

all of the sawed products are suitable for pallets, blocking, and similar uses (Craft and Baumgras 1978, 

1979; Craft and Emanuel 1981). In 

these studies, thinned trees were 

bucked into the longest pieces 

straight enough to yield Sound 

Square Edge 4-inch by 4-inch by 4- 

foot or larger cants (National 

Hardwood Lumber Association 

1974). Because of the prevalence 

of crook and sweep in the cut 

trees, there was a high percentage 

of sawable pieces less than 8 feet 

long. 

Most traditional hardwood sawing systems are designed for $-foot 

and longer logs. Many newer systems are designed for utilizing 

small-diameter trees but also process 8-foot or longer pieces. When 

utilizing trees from thinnings, 

sawing long pieces results in the 

loss of potential product yields 

because of crook and sweep. To 

quantify these losses, we determined yields of pallet lumber and 

cants from trees bucked into 8- 

foot and 10-foot lengths for processing and compared the resulting 

yields to predicted yields of the 

same trees if bucked into 4- and 6- 

foot lengths. 

One-fif th-acre circular plots 

were established in overstocked 

poletimber stands of northern, 

Allegheny, and upland hardwood 

timber stands. These plots were 

marked for thinning according to 

the appropriate stocking guides 

(Leak and others 1969; Roach 1977; 

Roach and Gingrich 1968). Each 

tree designated for removal was 

recorded by species and diameter 

at breast height (dbh). Two cut 

trees in each 1-inch dbh class from 

7 through 12 inches in each of four 

species groups were designated for 

bucking into 8-foot pieces, and also 

two trees in each dbh class were 

selected for bucking into 10-foot 

pieces. The species groups were: 

(1) yellow birch, hard and soft 

maple; (2) yellow-poplar, cucumbertree; (3) black cherry; and (4) 

red, white, and chestnut oak. 

Sample trees were selected at 

random from the cruise tally. 

Each sample tree was felled 

and marked to simulate bucking 

into 4- and 6-foot sawbolts. Sixfoot bolts were designated except 

where yield could be improved by 

cutting 4-foot bolts. Acceptable 

sawbolts included sound see tions 

with at least 5.6 inches diameter 

inside bark (dib) at the small end, 

and with sweep no more than 1-1/2 

inches in bolts 5.6 inches dib 

through 8.5 inches dib, or 2 inches 

in bolts larger than 8.5 inches dib. 

Diameters (outside bark) were 

measured at each bucking point, 

and deductions for bark thickness 

were made to derive small-end bolt 

scaling diameters. Potential sawed 

product yields from 4- and 6-foot 

bolts were predicted by applying 

the bolt dimensions to boltwood 

pallet stock yield tables (Craft and 

Emanuel 1981). 

After the bolt measurements 

were made, 52 of the sample trees 

were bucked into 8-foot lengths, 

and 49 were bucked into 10-foot 

lengths. Minimum acceptable 

piece dib was 5.6 inches. The sections were sawed on a single-saw 

circular headrig into the 4- by 4- 

inch and 4- by 6-inch eants and 

side lumber. The larger cant size 

was produced whenever the smallend piece dib was large enough. 

All side lumber was tallied to the 

nearest equivalent or multiple of 

4- and 6-inch wide pieces. The 

minimum acceptable piece was 4 

inches wide by 4 feet long. The 

yield was compared to the predicted yield of 4- and 6-foot bolts 

from the same tree. 

Net scale volumes (International 114-inch rule) for each sample 

tree were determined by applyihg 

the formula rule, to the nearest 

board foot, to the 8- or 10-foot 

sections cut from the tree, and the 

measured 4- or 6-foot bolt sections 

available from the same tree. 

Results and Diseussian 

Total Yields 

The total yield of side lumber 

plus cants from 8-foot sections 

averaged I1 percent less than predicted yield per tree from short 

bolts (Table 1). The total yield 

from 10-foot sections was 17 percent less than predicted yield from 

short bolts (Table 2). Paired 9" 

test indicated that the differences 

in long-section yields and the predicted bolt yields for all species 

were statistically significant at the 

0.99 level of probability (Table 3). 

Cant Yields 

In many operations, only eants 

are produced from small logs; side 

lumber is not recovered and cannot 

be considered part of the product 

yield. The cant-only yield per tree 

from 8-foot sections was 13 percent less than the predicted cantonly yield from bolts (Table I); 

yield of cants from 10-foot sections was 27 percent less than the 

predicted cant yield from bolts 

(Table 2). Paired "ttt test indicated 

the differences in long-section 

yields and the predicted bolt yields 

for qll species were statistically 

significant at the 0.99 level of 

probability for both length categories (Table 3). 
Table 1.--Comparison of yields from $-foot le to estimated bolt yields by 

Species 

Mean total yields Mean cant yields 

No. klean klean 

samples 8-foot bolt yield 8-foot bolt yield 

lengths improvement lengths improvement 

Birch, maple 

Y ellow-poplar , cucumbertree 

Cherry 

Oaks 

Board feetltree Percent Board feetltree Percent 

15 31.0 33.4 7.7 24.0 28.5 18.8 

All species 5 2 42.4 47.2 11.3 32.9 37.1 12.8 

Table 2.-=-€omparison of yields from 10-foot leqgths to estimated bolt yields by species group 

Species 

Mean total yields Mean cant yields 

No. Mean Mean 

samples 10-foot bolt yield 10-foot bolt yield 

lengths improvement lengths improvement 

Birch, maple 

Y ellow-poplar, 

cucumbertree 

Cherry 

Oaks 

Board feetltree Percent Board feet/tree Percent 

14 33.8 38.1 14.5 26.8 32.9 22.7 

All species 49 38.1 44.7 17.3 28.8 36.6 27.1 
mple statistics for the difference between actual 

md shortdolt yields, in feet 

Yield No. Mean Std. Min. Max. 

Species comparison samples differ- dev. value value t-value PR> I t 1 

(N) enee 

Cherry 

Bireh, maple 

Y ellow-poplar , eucumbertree 

Oaks 

All species 

Cherry 

Bireh, maple 

Y ellow-poplar , cueumbertree 

Oaks 

Bolts vs. 8' 

Bolts vs. 10' 

Bolts vs. 8' 

Bolts vs. 10' 

Bolts vs. 8' 

Bolts vs. 10' 

Bolts vs. 8' 

Bolts vs. 10' 

Bolts vs. 8' 

Bolts vs. 10' 

Bolts vs. 8' 

Bolts vs. 10' 

Bolts vs. 8' 

Bolts vs. 10' 

Bolts vs. 8' 

Bolts vs. 10' 

TOTAL YIELD 

CANT YIELD 

Bolts vs. 8' 12 5.9 13.3 -18.2 26.2 1.54 .I507 

Bolts vs. 10' 12 5.4 9.2 - 5.9 25.7 2.03 .0675 

All species Bolts vs. 8' 5 2 4.8 9.8 -18.2 27.1 3.75 .0008 

Bolts vs. 10' 49 6.5 10.7 - 8.0 44.5 4.25 .0001 
Comparisons of Tree-Scale Volume 

International ll4-inch scale 

volume for 4- and 6-foot bolts 

averaged about 20 percent more 

per tree than scale volumes for 8- 

and 10-foot sections from the same 

tree (Table 4). The diffecence was 

mainly due to scale deductions for 

crook and sweep in the 8- and 10- 

foot sections, The predicted total 

length of sawable short bolts averaged 1.8 feet more per tree than 

the actual totals for long-bolt 

bucking. This advantage for short 

bolts was offset because an average of 1.6 feet per tree for additional trim allowance is required 

for short-bolt bucking. The net 

advantage from the additional 

sawable bolt length was less than 1 

percent of total volume. 

Small-diameter , crooked roundwood can be sawed in 8-foot and 

longer lengths on single-sa w headrigs. But, in addition to losing 

potential product volume, the products will be shorter than parent 

log lengths. In this study, 8-foot 

pieces yielded 83 percent of product volume in 8-foot lengths; 10- 

foot pieces yielded only 57 percent 

of volume in 10-foot lengths (Table 

5). 

Many firms processing smalldiameter roundwood use twin-saw 

scrag-type headrigs. Feeding long, 

crooked pieces through these headrigs is extremely difficult. And, 

unless slab resaw equipment is 

available, the resulting product 

yields are even tower than experienced in our study. Regardless of 

the type of headrig used, processing crooked pieces lowers productivity. 

Table 4-Comparison of International 114-inch scale volume for trees cut into 8- 

or 10-foot lengths versus scale for Phe same trees cut into 4- and *foot 

length 

Species 

International International Gain in scale 

1/4-inch l/4-inch volume for 4- 

log scale bolt scale and 6-foot lengths 

Birch, maple 

Y ellow-poplar , cucumbertree 

Cherry 

Oaks 

Board feet/tree Percent 

8-FOOT LENGTHS 

All species 30.4 36.4 19.7 

Birch, maple 

Y ellow-poplar , cueurn bertree 

Cherry 

Oaks 

10-FOOT LENGTHS 

26.4 31.9 20.8 

36.0 43.0 19.4 

25.0 29.4 17.6 

27.1 31.6 16.6 

All species 28.5 34.3 20.4 
T&le 5-Sawed product yields from 8- and 10-foot pieces, by le 

product 

Cants only Total, cants and side lumber 

Length 

No. Volume (feet) No. Volu rn e 

Board Percent Board Percent 

feet feet 

8-FOOT LENGTHS 

Totals 144 1,778 100 289 2,381 100 

110-FOOT LENGTHS 

Totals 111 1,428 100 224 1,965 100 
Literatwe Cited 

Craft, E, Paul; Baumgras, John E. 

For. Serv. Res, Pap. HE-422. 

8 P* 

Craft, E. Paul; Baumgras, John E, 

Weight and volume yields from 

thim two oak-hickory 

stands. 1979; USDA For. Serv. 

Res. Pap. NE-448. 7 p. 

Craft, E. Paul; Emamuel, David M. 

Yield of met cants and lumber from poletimber thinnings. 

1981; USDA For. Serv. Res. 

Pap. NE-482. 8 p. 

Leak, William B.; Solomon, Dale S.; 

Filip, Stanley M. A silvicultwa1 guide for northern hardw 

in the Northeast. 1969; USDA 

For, Serv, Res. Pap, NE-143. 

34 p. 

National Hardwood Lumber Assoeiation. Rules for the measwe 

tion of hardwood and cypress lumber. Chicago, IL: Natl. Hardwood Lumber Assoc.; 1974. 115 p, 

Roach, Benjamin A. A stocking 

guide for Alle$hen 

and its use in eontr 

mediate cuttings. 1977; USDA 

For. Serv. Res. Pap. NE-373. 

30 p. 

Roach, Benjamin A.; Gingrich, 

Agric. Handb. 335. 35 p. 

U.S. GOVERW-ENT PRINTING OFFICE: 1982-505-012:32 
Craft, E. Paul. Tke effect of sawbolt lengtR on the yield of pallet 

materials from small-diameter wood trees. Broomall, PA: 

Northeast. For. Exp. Stn.; 2982; USDA For. Serv. Res. Pap. NE499. 6 p. 

From overstocked poletimber thinnings, 52 sample trees were 

bucked into 8-foot lengths, and 49 trees were bucked into 10-foot 

lengths. These lengths were sawed into pallet parts and pallet 

cants. The sawed yield from 8- and 10-foot lengths is compared to 

the predicted yield from sawing 4- and 6-foot bolts from the same 

trees. 

Ke~osrfs: Produet yields, poletim ber thinnings, pallet parts, and 

cants 
rs of the Northeastern Forest Experiment Station are in 

Bmmall, Pa. Field laboratories are maintained at: 

husetts, in cooperation with the University of 

in cooperation with Berea College. 

@ Burlin@on, Vermont, in cooperation with the University of 

Vermsnt. 

@ Cielaware, OW. 

phise, in cooperatbn with the University ab 

a Hmden, Comaticut, in cooperation with Yale University. 

QI Margatown, West Virginia, in cooperation with West Virginia 

University, Morgantown. 

@ Omm, Maine, in cooperation with the University of Maine, 

Orona. 

@ Parsons, West Virginia. 

@ Rineeton, West Virginia. 

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

New Ysrk College of Environmental Sciences and Forestry at 

Syracuse University, Syracuse. 

@ University Park, Pennsylvania, in cooperation with the 

Pelmsylvanria State University. 

@ Warren, Penmylvania.