United States 

Forest Service 

West Virginia Yellow-Poplar 

Lumber Defect Database 

Northeastern Forest 

Experiment Station 

Research Paper-NE-660 Lawrence E. Osborn 

Charles J. Gatchell 

Curt C. Hassler 
-- - 

Abstract 

In West Virginia, yellow-poplar (Liriodendron tulipifera) is abundant and is a prime 

candidate for increased utilization in a variety of manufacturing industries. Computer 

simulations are a cost-effective tool for estimating potential cutting yields from lumber. 

They can be used to promote increased use of yellow-poplar in the furniture, cabinet, 

and architectural woodworking industries and may also lead to increased utilization 

of the lower grades of lumber. This paper describes the data collection methods 

and the format of the new West Virginia yellow-poplar lumber defect database that 

was developed for use with computer simulation programs. The database contains 

descriptions of 627 boards, totaling approximately 3,800 board feet, collected in 

West Virginia for grades FAS, FASIF, No. 1 Common, No. 2A Common, and No. 

28 Common. 

The Authors 

LAWRENCE E. OSBORN received a B.S. degree in forestry from the University 

of Illinois in 1981 and an M.S. degree in forestry from Virginia Polytechnic 

lnstitute and State University in 1985. He is currently a research associate at 

the Appalachian Hardwood Center, Division of Forestry, West Virginia University, 

Morgantown, West Virginia. Before arriving at WVU, he held a research position 

at Virginia Tech and directed the Building Materials Management & Technology 

program at the University of Massachusetts. 

CHARLES J. GATCHELL received a B.S. 'degree in forestry from the University 

of Massachusetts in 1955 and an M.S. degree in wood-products engineering 

from the New York State College of Forestry at Syracuse University in 1961. 

He is currently a research forest products technologist engaged in research on 

yields of low-grade lumber from gang ripping and the suitability of use of these 

yields for solid wood furniture and cabinets. From 1965 to 1989, he was Project 

Leader of Princeton's utilization research work unit and conducted research on 

wood used in highway construction and on the conversion of small-diameter 

logs and low-grade lumber to rough-dimension furniture parts. 

CURT C. HASSLER received his B.S. degree in forestry from West Virginia 

University in 1975 and an M.S. degree (1978) and Ph.D. degree (1985) in 

forestry from Virginia Polytechnic Institute and State University. He is currently 

an Associate Professor and the leader of the Appalachian Hardwood Center, 

Division of Forestry, West Virginia University, Morgantown, West Virginia. Before 

arriving at WVU, he held research positions at the University of ArkansasMonticello, the University of Minnesota, and Virginia Tech. 

Manuscript received for publication 13 August 1991 

Northeastern Forest Experiment Station 

5 Radnor corporate Center 

100 Matsonford Road, Suite 200 

Radnor, Pennsylvania 19087-4585 

February 1992 
Introduction 

Second-growth yellow-poplar (Liriodendron tulipifera) is 

plentiful in West Virginia. There are 10.5 billion board 

feet of growing stock, and annual growth exceeds annual 

removals by approximately seven to one (DiGiovanni 

1990). Because yellow-poplar is abundant, it is a prime 

candidate for increased utilization in a variety of 

manufacturing industries. Also, the constantly rising prices 

of all lumber grades make appropriate grade selection 

even more important for industries that already use yellowpoplar. 

The quality of yellow-poplar sawtimber is heavily weighted 

toward the lower quality sawlogs with 33 percent in Grade 

3 logs and 37 percent in Construction Grade logs 

(DiGiovanni 1990). As a result, a large volume of No. 2 

Common yellow-poplar lumber is being produced for which 

there is little market demand. 

An understanding of potential cutting yields from yellowpoplar may lead to increased use in the furniture, cabinet, 

and architectural woodworking industries and may also 

lead to increased utilization of the lower grades of lumber. 

Computer simulations of rough-mill operations should give 

reasonable estimates of such yields. However, no suitable 

yellow-poplar lumber database with mapped defects existed, 

so one was created. 

This paper describes the data collection methods and the 

format of the new West Virginia yellow-poplar lumber 

defect database. The database is available upon request 

on a 3.5-inch floppy disk that contains a "combined faces" 

file and a "better face only" file. 
Table 1.-Composition of 414, kiln-dried yellow-poplar database 

Gradea No. of Item NHLA Length Cutting 

boards width areab 

FAS 

FASl F 

No. 1 

No. 2A 

I No. 28 

120 Mean 7% 6 139 92.05 

s.d.' 2 34'%6 6.45 

Minimum 5% 96 83.33 

Maximum 1 53/16 192 1 10.70 

45 Mean 7% 136% 92.35d 

s.d.' 1 l3k6 32% 6.31 

Minimum 5% 96 83.33d 

Maximum 13l?46 192 1 05.00~ 

163 Mean 63/1 61227~~ 84.23 

s.d.' 1% 41 3/i 10.03 

Minimum 3% 48 66.90 

Maximum 1 2% 192 11 9.58 

163 Mean 6% 

s.d.' 1% 

Minimum 3Y4 

Maximum 11Y4 

136 Mean 6Y4 1 223~ 71 .35e 

s.d.' 1 Y4 44% 14.41 

Minimum 21 x6 48 50.0ge 

Maximum 1 15/8 192 1 24.42e 

Total 627 Mean 6Y4 1 29IY16 78.55 

s.d.' 1'346 42% 6 15.15 

Minimum Zi1/16 48 50.03 

Maximum 1 s3/16 192 137.17 

'Graded according to NHLA Special Kiln-Dried Rule. 

b"Cutting area" refers to the percentage of the surface measure of a board contained within the NHLA cuttings taken during grading. 

%.d. = Standard deviation ofsthe sample. 

d"Cutting area" for FAS1 F boards was based on the NHLA cuttings taken on the better face of the boards. 

e"Cutting area" for the No. 2B boards was based on sound cuttings. 

Methods 

The yellow-poplar database contains descriptions of 627 

boards totaling approximately 3,800 board feet. Lumber 

was collected from two large distributors operating in 

central West Virginia. These companies obtain logs from 

as many as six counties. All boards were 414, graded 

green before kiln-drying, then surfaced on both sides, 

and carefully regraded using the National Hardwood Lumber 

Association's (NHLA) Special Kiln-Dried Rule (NHLA 

1990). 

A general description of the database boards by NHLA 

grade, width, length, and grade cutting surface area is I shown in Table 1. Very little yellow-poplar is sold as 

Saps, Selects, or No. 3 Common, so these grades were 

not included in the study. Board widths and lengths were 

measured to the nearest %6 inch. Grade cutting surface 

area is the percentage of the surface measure of a board 

that is contained within the NHLA cuttings taken during 

grading. 

The mean cutting surface areas shown in Table 1 are 

well above the minimums specified for each grade. For 

No. 1 Common and No. 28 Common, the means appear 

to exceed the minimum requirements for a higher grade. 

National Hardware Lumber Association grading rules specify 

minimum cutting yield, minimum cutting size, maximum 

.number of cuttings, and type and size of any allowable 

defects for each grade. During the course of lumber grading, 

every attempt was made to maximize the cutting surface 

area. Whenever additional cuttings were permitted by the 

grade rules, these cuttings were taken if they resulted in 

an increased cutting surface area for a particular board. 

Many boards that could not meet the requirements for a 

particular grade had high cutting surface areas under the 
Table 2.-Distribution of width and length by NHLA grade of 414 kiln-dried yellow-poplar database boards 

Board Board length groupC 

Gradea No. of width Subtotals 

- boards groupb A B C 

F AS 120 A od od od od 

B. od 48 52 100 

C od 13 7 20 

No. 1 163 

No. 2A 163 

No. 2B 136 

Subtotals 627 A 40 36 46 122 

B 83 171 191 445 

C 6 26 28 60 

Total 627 129 233 265 627 

aGraded according to NHLA Special Kiln-Dried Rule. 

b~oard width group: A = width a 2% and < 5% inches. 

B = width a 5% and < 9% inches. 

C = width 2 9% inches. 

'Board length group: A = length 3 4 feet and < 8 feet. 

B = length 3 8 feet and < 12 feet. 

C = length 3 12 feet and s 16 feet. 

d~his widthilengthlgrade combination not permitted under NHLA Special Kiln-Dried grading rules. 

less restrictive requirements of a lower grade. The mean 

cutting surface area for No. 1 Common database boards 

is 84.23 percent, which is higher than the 83.4 percent 

minimum required for FAS. Many boards that otherwise 

yielded enough clear cutting surface area to make FAS 

or FASlF were downgraded to No. 1 Common due to 

stain or discoloration, which are limited in FAS and FASlF 

but not limited in the lower grades of yellow-poplar, resulting 

in the "high" mean cutting surface area. For No. 2B 

Common database boards, the mean cutting surface area 

is 71.35 percent, which is higher than the 66.7 percent 

minimum required for No. 1 Common. However, the cutting 

surFace area for No. 2B Common boards is based on 

sound cuttings, not the clear cuttings that are required in 

the higher grades. 

The distribution of boards by grade, width, and length is 

shown in Table 2. Although most of the lumber for this 

study was purchased as random width and random length, 

a conscious attempt was made to include a wide range 

of board widths and board lengths within each grade. 

The width and length group classificakions used in Table 

2 were created to assure that all general types of boards 

were represented in the database. The goal was to produce 

a database from which potential users could draw 

subsamples that represent their own board distributions. 

Lumber Grading 

. Even though each board was purchased under a particular 

grade (graded green), the grade of each board was carefully 
Table 3.-Range of board surface measure (SM), in percent, contained within NHLA cuttings for each NHLA 

grade and each subgrade 

Gradea NHLA cutting 

yield range Subgrade Subgrade range 

Percent of SM Percent of SM 

No. 2A 

& 

No. 28 

No. 1 

50.000 thru 66.665b 

(611 2 to 811 2) 

66.666 thru 83.332b 

(811 2 to 1011 2) 

- 50.000 thru 55.555 

0 c 55.556 thru 61.1 11 

+ 61.1 12 and greaterC 

- 66.666 thru 72.221 

0 72.222 thru 77.776 

+ 77.777 and greaterC 

FAS 83.333 thru 100 - 83.333 thru 88.888 

& (1 011 2 thru 1211 2) 0 88.889 thru 94443 

FASl F + 94.444 and greatef 

aGraded according to NHLA Special Kiln-Dried Rule. 

bCutting yield range acJually extends into the range for higher grades and can exceed 100 percent without a board making a higher 

. grade due to failure to meet other grade requirements such as minimum cutting size, cutting type (clear or sound cuttings), number 

of cuttings permitted, amount of stain or discoloration, etc. 

'Actual cutting yield can exceed 100 percent of the surface measure of a board due to "rounding off' error when surface measure is 

estimated using a tally stick and because entire board length can be utilized in NHLA cuttings, but length is rounded down to the 

nearest whole foot when estimating surface measure. 

recalculated in the laboratory to assure accurate grading. 

Grading was performed by two individuals in constant 

consultation with each other. When necessary, a certified 

NHLA lumber grader or the NHLA rules authority was 

consulted. Before grading, all boards were kiln-dried and 

then surfaced on both faces to a thickness of 0.8125 

(I%) inch. This greatly facilitated the process of measuring 

and locating defects on the faces of the boards compared 

to working with rough lumber. Boards were then carefully 

regraded using the NHLA Special Kiln-Dried Rule for 

rough, kiln-dried yellow-poplar. According to this rule, 

boards are graded as if they were air-dried. Any defects 

that result from drying affect the grading process and 

were included in the database, with the exception of 

warp, even though it is a defect according to the NHLA 

Special Kiln-Dried Rule. This contrasts with the NHLA 

Standard Kiln-Dried Rule which specifies that checks and 

warp shall not be considered defects. Other defects are 

clearly visible on rough lumber. Therefore, surfacing the 

boards before regrading and using rules for "rough lumber 

should have had no affect on the resulting grades. 

According to the NHLA rules for standard grades, 10 

percent of the minimum-width boards in each grade are 

permitted to be %-inch scant. The NHLA Special Kiln-Dried 

Rule permits those boards to be an additional %-inch 

scant in width due to shrinkage during drying. Therefore, 

the minimum width permitted for FAS and FASIF boards 

was 5-I/z inches. The minimum width permitted for No. 1 

and No. 2 Common boards was 2-% inches. 

In grading each board, every effort was made to determine 

the highest legitimate grade. Once that grade was 

determined, the grader selected the strategy that maximized 

the number of NHLA cutting units that could be obtained 

- 

from the board while still maintaining the grade. For 

example, whenever an "additional" cutting could be taken 

that increased the yield of cutting units without lowering 

the grade of the board, the cutting was taken. 

Subgrades 

Once the NHLA grade and yield of the boards were 

accurately determined, each board was then assigned a 

"subgrade" (variable 0 in Appendix B) based on the 

percentage of the board surface measure contained within 

the cuttings (variable MMM.MM in Appendix B). A subrade 

of "-" was assigned to each board with a percentage 

yield MMM.MM in the lowest third of the range for the 

NHLA grade of that board. A subgrade of "0 was assigned 

to each board with a percentage yield in the middle third 

of the range for the NHLA grade of that board. A subgrade 

of "+" was assigned to each board with a percentage 

yield above the middle third for the NHLA grade of that 

board. The ranges for each subgrade are shown in Table 

3. The number of boards in each subgrade is shown in 

Figure 1. The number of boards in each subgrade, by 

grade, is shown in Figure 2. These distributions are not 

entirely random. The subgrade designation was used 

merely to assure that all types of boards were included 

in the database. 

Defect Codes 

During grading, every defect on each face was identified 

on the surface of the board by a defect-type code (Table 

4). Defects less than or equal to %-inch in average diameter 

may be permitted in NHLA cuttings depending on the 

type, size, and number of the defects, and the type and 

size of the cutting. However, the equipment used to map 
Number of Boards 

- LOW 0 MEDIUM + HIGH TOTAL 

Subgrade 

Figure 1 .-Distribution of boards within each subgrade for yellow-poplar 

database. 

Number of Boards 

FAS FASl F 1C 2A 2B 

NHLA Lumber Grade 

Subgrade 

gzg - LOW 

0 MEDIUM 

0 . . ::. . ...... . :.:. . . + HIGH . . .. : .: . 

TOTAL 

Figure 2.-Distribution of boards within each subgrade by NHLA grade for 

yellow-poplar database. 
Table 4.-Defect-type codes used in the yellow-poplar 

data base 

Code Descriptiona 

BP Bark pocket 

CB Cross break 

CH Check 

CR Crook 

DD Discoloration (mineral), dark 

DL Discoloration (mineral), light 

HO Hole 

KL Knot, loose 

KT Knot, tight (includes burls) 

KU Knot, unsound 

PI Pith 

RO Rot 

SH Stain, heavy 

SK Shake 

SL Stain, light 

SP Split, end 

WA Wane 

aDefect definitions can be found in Appendix A. 

defects was accurate only to the nearest 'h inch, and 

defect dimensions were automatically rounded up to the 

nearest 1/4 inch during defect mqpping (for example, any 

defect less than %-inch average diameter was recorded 

as l/4 X % inch). However, the defect size often determines 

the acceptability or unacceptability of defects that are % 

inch or less in average diameter when using NHLA or 

other grade rules. Therefore, these defects were assigned 

a defect-size code, a single number or letter which indicated 

the actual average diameter of the defect in thirty-seconds 

of an inch. The numbers 1 through 9 correspond to '132 

through Y32. The letters A through G correspond to '0/32 

through 1%~. For splits, cross breaks, and checks, this 

code refers to the maximum width of the gap, regardless 

of the length of the defect. Other defects greater than %- 

inch average diameter are never permitted in NHLA cuttings 

and were, therefore, not assigned a size code. 

Special Considerations 

There are several characteristics of yellow-poplar lumber 

that required special consideration during the course of 

grading the boards. Bud traces, adventitious buds, and 

pin knots are names applied to the same characteristic, 

one that is very common in yellow-poplar. If the 

characteristic is sound (solid across the face) and light in 

color (not black), it is not considered a defect under 

NHLA rules. An informal survey of yellow-poplar users 

performed by the researchers revealed no application 

where these characteristics were considered to be. defects, 

so they were not included in the database. When these 

characteristics were found to be unsound or black, they 

are defects according to NHLA rules and were included 

in the database and treated as unsound knots. 

Stain and discoloration are characteristics that are 

limited only in FAS and FASlF yellow-poplar boards and 

are not defects in the other grades. However, there are 

many applications where these characteristics are 

considered defects in the finished product. Therefore, 

stain and discoloration were recorded in the database. 

This allows the database user to make the decision as 

to whether stain and discoloration are defects. 

Defect Mapping and Digitizing 

After grading, the pertinent information about each board 

and its defects was recorded in the computer database. 

This was accomplished through the use of a Numonics 

Corporation 1224 Graphics Calculator.' This device uses 

a transverse arm mounted on rails to allow a pointer to 

move along the entire face of a board. Optically scanned 

lines communicated the pointer's precise position to the 

graphics calculator. The information recorded included 

board number, a board supplier identification code, NHLA 

board width, board rectangle width, board length, grade 

of the board as mapped in this study, surface measure, 

number of NHLA cuttings taken during grading, number 

of NHLA cutting units, and crook information. Defect 

information recorded included defect-type code, defect-size 

code, location on board rectangle, and face of defect 

location (better or worse face of board). 

The input to the database from the graphics calculator 

consisted of pairs of X,Y coordinates on a 'h X %inch 

grid corresponding to the lower left (LX, LY) and upper 

right (UX, UY) corners of the smallest rectangles completely 

surrounding each defect. These defects were located 

within the board rectangle, defined as the smallest rectangle 

on the grid system that completely surrounded the board 

and any crook in the board. The %-inch grid system and 

a unique origin at (0,0), which was the same physical 

corner of the board regardless of which face was being 

mapped, were used to map all natural defects on each 

face of each board with the exception of crook. For the 

purposes of this study, crook is defined as a void along 

either edge of the board between the board outline and 

the rectangle on the grid system enclosing the board. 

Crook was assumed to be the same throughout the 

thickness of the board and was, therefore, only recorded 

with the defect information for the better face of each 

board. 

Each natural defect was mapped according to the rectangle 

on the %inch grid that completely surrounded it. This 

overestimated the size of nearly every defect. Diagonal 

defects and very large irregularly shaped defects such as 

crook, wane, checks, splits, pith, shake, stain, and 

discoloration were often mapped as a series of smaller 

rectangles to minimize the amount of clear area labeled 

as defective. However, ih no. instance was a large defect 

'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. 
Number of Boards 

Crook (inches) 

Figure 3.-Number of boards for each size class of crook when measured 

along the bottom edge of boards. (Crook was rounded up to the 

nearest inch.) 

mapped as a series of subdefects in a way that might 

lead to the acceptance of prohibitively large defects in 

any subsequent use of the database. For example, large 

knots, holes, bark pockets, and similar defects were never 

divided into subdefects measuring % inch or less in average 

diameter. Defects that were less than lh inch in average 

diameter were never subdivided. Checks, splits, and similar 

defects were never divided into subdefects 6 inches or 

less in length. In practice, any subdefects other than 

wane and crook were still very large. 

To speed data collection, and because they are permitted 

in any number on the sound face of clear face cuttings, 

clusters of defects '/a inch or less in average diameter 

and of the same type were usually mapped as a single 

defect. Defects larger than '/a inch in average diameter 

were mapped individually. 

Mechanical defects due to particular machining and handling 

techniques characterize the limitations of the personnel 

and equipment used to process the raw material into 

lumber, not the nature of the material itself. For this reason, 

mechanical defects were not treated as defects and were 

not included in the defect database. The format for the 

database is described in Appendix B. 

Preliminary Analysis of the Crook Defect Data 

Because the amount of crook in a board is important 

when making decisions concerning secondary processing 

of lumber, a preliminary analysis of crook data was 

performed. During the process of defect mapping, boards 

were positioned against a fence in such a way that the 

edge with the most concave crook was in contact with 

the fence at two points (usually the ends of the boards). 

The fence served as the Y-axis (Y=O), and crook was 

measured between the edge of the board and the fence. 

Crook defects were recorded only for the better face of 

each board and are assumed to be the same throughout 

the thickness of the board. Actual crook measurements 

were rounded up to the nearest inch. When the upper 

edge of the board deviated from a straight line, crook 

defects were mapped to the upper edge of the board 

rectangle. 

Figure 3 shows the number of boards in each size class 

of crook when measured along the bottom edge of the 

boards. The majority of the boards, 70 percent, had 

inch or less crook, 21 percent had l/2 inch of crook, and 

the remaining 9 percent of the boards had crook between 

3/4 and 2 inches. Those boards for which zero crook was 

recorded had to meet a particular set of conditions. 

Actual crook, if any, had to be less than '/8 inch and the 

NHLA width of the board had to be equal to the rectangle 

width. 
Summary 

The yellow-poplar lumber defect database contains complete 

board and defect descriptions for 627 boards in grades 

FAS, FASlF, No. 1 Common, and No. 2 Common. The 

database can be used as a whole or subsamples, which 

represent a user's own particular distribution of board 

types, can be drawn from it. The data were collected for 

use with computer programs that simulate rough-mill 

operations. The goal was to be able to estimate yields 

for specific products and to examine the feasibility of 

utilizing lower grade material for those products. 

All data for the 627 boards are stored in two separate 

DOS text files (DOS 3.3) on a single 3.5-inch floppy 

disk. One file with the name YPDB.BTR contains the 

defect information for just the better faces of the boards. 

The second file is the combined faces database, named 

YPDB.CMB, and contains the defect information for both 

the better face and worse face of each board. 

Database floppy disks are available on request from either 

of the following locations: 

USDA Forest Service 

Rt. 2 BOX 562-8 

Princeton, WV 24740-9628 

(304) 425-81 06 

Appalachian Hardwood Center 

Division of Forestry 

West Virginia University 

P.O. Box 6125 

Morgantown, WV 26506-61 25 

(304) 293-7550 

Literature Cited 

DiGiovanni, Dawn M. 1990. Forest statistics for West 

Virginia-1975 and 1989. Resour. Bull. NE-114. Radnor, 

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

Northeastern Forest Experiment Station. 172 p. 

National Hardwood Lumber Association. 1990. Rules for 

the measurement and inspection of hardwood and 

cypress. ~emphis, TN: National Hardwood Lumber 

Association. 108 p. 
Appendix A: Defect Definitions 

Bark pocket A bark-filled blemish on the face of a 

board. 

Cross break A separation of the wood across the 

grain that extends to the long edge of 

the board. (Splits extend to the end of a 

board.) 

Check 

Crook 

A lengthwise separation of the wood 

that usually extends across the annual 

growth rings and commonly results from 

stresses set up in wood during seasoning. 

For the purposes of this study, the defect 

could not extend to the end of the 

board. 

Deviation edgewise from a straight line 

from end to end of a piece of lumber, 

measured at the point of the greatest 

distance from the straight line. For the 

purposes of this study, crook is a void 

along either edge of a board between 

the board outline and the rectangle on 

the 0.25 X 0.25-inch grid system which 

completely surrounds the board. 

Discoloration, A black discoloration of undetermined 

dark cause. Also often referred to as mineral 

stain. 

Discoloration, An olive to greenish-black, brown, or 

light purple discoloration of undetermined 

cause. Also often referred to as mineral 

stain. 

Hole National Hardwood Lumber Association 

grading rules assign different names to 

distinguish between holes of different 

sizes (that is, pin worm holes, spot worm 

holes, shot worm hole, grub holes). For 

this study, all holes were assigned the 

same defect-type code, HO, and the 

defect size code was used to distinguish 

between different sizes. 

Knot, loose 

Knot, tight 

Knot, unsound 

Pith 

Rot 

Shake 

Stain, heavy 

Stain, light 

Split, end 

Wane 

A knot that is not held tightly in place 

by growth or position, one that cannot 

be relied on to remain in place. This is 

an unsound defect, even if the knot 

itself is solid across 

A knot that is fixed by growth or position 

so as to retain its place. For the purposes 

of this study, this also refers to a sound 

knot, one that is solid across the face 

and of the same hardness as the 

surrounding wood. 

A knot that is tight but is not solid across 

the face either due to the presence of 

seasoning checks, decay, or a soft pith. 

The small, soft core that occurs in the 

center of a log or branch. 

Refers to any area of advance or incipient 

decay in the wood aS evidenced by 

color and softness when compared to 

the surrounding wood. 

A separation along the grain, the greater 

part of which occurs between the annual 

growth rings. 

Black discoloration of the wood due to 

sapstain or surface fungi. 

Grey, blue, or pink discoloration of the 

wood due to sapstain or surface fungi. 

A lengthwise separation of the wood, 

due to the tearing apart of wood cells. 

For the purposes of this study, the defect 

had to extend to the end of the board 

in order to be classified as a split, 

otherwise it was called a cross break. 

Bark or any absence of wood on the 

edge or corner of the board. 
Appendix B: Database Format 

For each board, the first three lines of code are the 

board header data which describe the board itself: 

where: 

b = 1 blank space. 

AAA = 3-digit board number. 

BB = 2-character board grade as mapped 

(FA, 1 F, lC, 2A, or 28). 

CCC = Number of defects on the entire board. 

DDD = Number of defects on the better face. 

EEE = Lowest X coordinate of board (0). 

FF = Lowest Y coordinate of board (0). 

GGG = Greatest X coordinate of board (board 

length). 

HH = Greatest Y coordinate of board (rectangle 

width). 

11.111 = Precise board wtdth measured at % of the 

board length from narrower end in inches 

(NHLA width). 1 J = 1 -character board supplier identification 

code (C, R, or V). 

KK = NHLA surface measure of board in square 

feet. 

L = Number of cuttings plotted during NHLA 

grading. 

MMM.MM = Percentage of surface measure contained 

within NHLA cuttings that was computed 

using Equation 1. 

NNN.NN = Cutting units contained within NHLA 

cuttings. 

I 0 = 1 -character subgrade designation, where: 

"-" refers to boards with NHLA yields 

(NNN.NN) in the lowest third of the standard 

limits for the board's grade, "0 refers to 

boards with NHLA yields in the middle 

third, and "+" refers to boards with 

NHLA yields above the middle third of the 

normal range for that board's NHLA grade 

(Table 3). 

For each defect, one line of code describes the defect 

using the following format: 

where: 

b 

PPP 

QQ 

RRR 

SS 

TT 

U 

= 1 blank space. 

= Lowest X coordinate of defect rectangle. 

= Lowest Y coordinate of defect rectangle. 

= Greatest X coordinate of defect rectangle. 

= Greatest Y coordinate of defect rectangle. 

= 2-character defect-type code (Table 4). 

= 1 -character defect-size code (average 

diameter) for defects to '6/32 inch. The 

numbers 1 through 9 correspond to %2 

through 9/32. The letters A through G 

correspond to 10h~ through l%2. 

= Face of defect location (1 =better, 

2 =worse). 

A sample of the combined-faces database for board 151 

and the 7 defects on it (2 on the better face, 5 on the 

worse face), and board 152 and the 11 defects on it (7 

on the better face, 4 on the worse face) follows: 
Osborn, Lawrence E.; Gatchell, Charles J.; Hassler, Curt C. 1992. West 

Virginia yellow-poplar lumber defect database. Res. Pap. NE-660. 

Radnor, PA: U.S. Department of Agriculture, Forest Service, Northeastern 

Forest Experiment Station. 10 p. 

Describes the data collection methods and the format of the new West 

Virginia yellow-poplar lumber defect database that was developed for use 

with computer simulation programs. The database contains descriptions 

of 627 boards, totaling approximately 3,800 board. feet, collected in West 

Virginia in grades FAS, FASlF, No. 1 Common, No. 2A Common, and 

No. 2B Common. The database includes a complete description of each 

board and each defect on the boards in a format that is readily acceptable 

for use with different simulation programs. 

Keywords: Lumber, wood defects, Liriodendron tulipiera 

U.S. GOVERNMENT PRINTING OFFICE: 1991--648-139/40.011 

* 
Headquarters of the Northeastern Forest Experiment Station is in Radnor, Pennsylvania. Field laboratories are maintained at: 

Amherst, Massachusetts, in cooperation with the University of Massachusetts 

Burlington, Vermont, in cooperation with the University of Vermont 

Delaware, Ohio 

Durtiam, 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 

Orono, Maine, in cooperation with the University of Maine 

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 

University Park, Pennsylvania, in cooperation with The Pennsylvania State University 

Warren, Pennsylvania 

Persons of any race, color, national origin, sex, age, religion, or with any handicapping condition are welcome to use and enjoy all facilities, programs, and services of 

the USDA. Discrimination in any form is strictly against agency policy, and should be 

reported to the Secretary of Agriculture, Washington, DC 20250. 

'Caring for the Land and Serving People Through Researchm