U.S. FOREST SERVICE RESEARCH PAPER FPL 9 OCTOBER 1963 I I I I 

SERVICE 

VENEER GRADES 

U. S. DEPARTMENT OF AGRICULTURE 

for the development 

FOREST PRODUCTS LABORATORY 

of hardwood veneer log grades 

FOREST MADISON, WIS. 
SUMMARY 

The quality of a log or tree refers to 

those properties that make it suitable 

for conversion into end products for a 

given use, and leads to a system of 

sorting the products into groups with 

similar characteristics . The research reported herein was 

conducted for the purpose of establishing 

hardwood veneer grades to be used in 

developing hardwood veneer log and bolt 

grades. The recommended Forest Products Laboratory hardwood veneer grades 

attempt to reduce the need for individual 

judgment required by specifying type, 

number, distribution, and size of defects 

permitted in each grade. 

Studies were made at four veneer mills 

on yellow birch, hard maple, and redgum. 

The FPL hardwood veneer grades segregated veneer in the green condition into 

groups that reflect the utility of the veneer in the dry condition. 
RECOMMENDED VENEER GRADES 

for the development of hardwood veneer 

log grades 

by 

JOHN W. HENLEY, 1 Technologist 

RICHARD 0. WOODFIN, JR., Technologist 

HENRY H. HASKELL, Technologist 

Forest Products Laboratory , 

2 Forest Service 

U. S. Department of Agriculture 

INTRODUCTION 

One major research problem in the 

field of quality evaluation that was recognized by the U.S. Forest Service Log 

Grade Committee was the development 

of hardwood veneer log grades. Before 

veneer bolt and log grades can be developed, standard hardwood veneer grades 

are required. This need reflects one of 

the basic concepts outlined by the Log 

Grade Committee: that is, the end product must have well-defined standards or 

grades before a grading system can be 

developed for logs or trees that produce 

the end product. The existing hardwood 

veneer grading rules are not specific 

1 

Now with the Pacific Northwest Forest and Range 

Experiment Station, Portland, Oreg, 

and leave much to the judgment of the 

grader. Also, the existing grades do not 

specify the number and size of defects 

allowed in the various grades. Veneer 

grading systems were found to vary with 

the individual plant, the grader, and plant 

procedures. Such grade systems did not 

have consistent relationships nor express a specific market value. 

The Forest Products Laboratory has 

developed and completed the evaluation 

of a hardwood veneer grading system 

that can be used to develop grades for 

hardwood veneer logs and bolts. The 

grades in general follow the specifica2 

Maintained at Madison, Wis., in cooperationwith 

the University of Wisconsin. 

1 
3 

tions of the Hardwood Plywood Institute 4 

and the Commercial Standard, CS 35-61. 

However, an attempt has been made to 

reduce the need for judgment required of 

a grader by specifying the type, number, 

distribution, and size of defects permitted in each grade. 

Four studies have been completed that 

were designed to evaluate the performance of the recommended veneer grades 

in segregating veneer into categories 

that reflect utility of the veneer. These 

studies were conducted at the following 

locations: 5 A Vermont mill producing 

yellow birch (Betula alleghaniensis) veneer for door skins; two Wisconsin mills, 

one producing yellow birch veneer for 

wall panels and door skins, and the other 

producing hard maple (Acer saccharum] 

veneer for chair seats and backs; and a 

Georgia mill where redgum (Liquidambar styraciflua) veneer was produced for 

stock plywood panels. 

The approach taken in testing the veneer grades was to determine the utility 

of the veneer segregated by the grading 

rules for various uses, species, and 

areas of production. 

GENERAL INSTRUCTIONS 

1. These grades are to be applied to 

veneer strips of the spurred or clipped 

length produced from a bolt or log and 

with a minimum green width of 6 inches. 

There is no maximum width of strip. 

Length refers to the distance along the 

grain of the veneer, and width refers to 

the distance across the grain. 

2. All veneer strips shall be measured 

at the narrowest part of the piece and 

without allowance for trimming or 

shrinkage. Strips with the minimum width 

must have sound edges. 

3. Defects (except splits) 1/64 inch 

wide. or less, across the grain can be 

considered as removed with one cut of 

the clipper. 

4. Grades must be applied to recover 

the maximum amount of the highest grade 

veneer. 

5. All veneer that does not meet the 

grade specifications is termed “residue.” 

DESCRIPTION OF TERMS USED I N T H E G R A D E S 

Grading Defects 

A defect, as used here, is defined as 

any irregularity occurring in or on wood 

that adversely affects its appearance, 

strength, durability. or utility values. 

The defects specifically recognized in 

these grades are described below. When 

characteristics not described in these 

grading specifications are encountered 

3 

Hardwood Plywood Institute. Hardwood Plywood 

Manual, Second edition, pp. 9-10. 1962. 

4 

U.S. Dept. of Commerce. Commercial Standard 

CS 35-61, Hardwood Plywood. 1961. 

5 

Appreciation is extended to the following companies for their assistance and cooperation in 

permitting these research studies to be conducted at their veneer mills: the Bradley Plywood Corp., Savannah. Ga.; the Larson Plywood 

Co., Sheboygan, Wis.; the Owens-Illinois Plywood Co., North Troy, Vt.; and the Penokee 

Veneer Co., Mellen, Wis. 

2 FPL-9 
they will be considered in relation to are measured to the nearest one-quarter 

described defects according to their inch and further classified into two 

adverse effect on appearance, strength, 

durability. or utility values of the veneer. 

The following characteristics 

groups: 

(1) Sound knots are solid and firmly 

fixed in the piece of veneer of which they 

or pith larger than 1/64 inch. 

are grading defects and their presence is are a part. Sound knots have no openings limited by the grading specifications: 

characterized by low shock resistance 

Brashness.---A condition of wood (2) Open knots or knotholes are voids 

where a portion of or all of the knot has 

for the species and by abrupt failure 

across the grain without splintering 

when the piece is bent only a small 

amount. 

Cross break.--Separation of the wood 

cells across the grain of the veneer piece; 

usually accompanied by splintering. 

Decay.--A disintegration of the wood 

substance due to the action of wooddestroying fungi. Decay that has not proceeded far enough to soften or otherwise 

perceptibly impair the hardness of the 

wood but usually accompanied by a slight 

discoloration or bleaching that gives the 

wood a dull and lifeless appearance is 

termed incipient decay. However, it is 

not recognized as a separate grading 

defect. 

Gum spots. - -Well-defined accumulations of solid gum that occur between 

displaced wood elements. Sound gum 

spots have no openings larger than 

1/64 inch. An open gum spot has an 

opening larger than 1/64 inch. 

Holes.--Openings resulting from 

mechanical damage. 

Knots,--Cross or longitudinal sections 

of limbs with grain running at about right 

angles to the grain of the veneer of which 

they are a part. Knot size is determined 

by the character of the grain of the knot 

and is measured at the points where the 

grain of the knot is most differentiated 

from that of the surroundingwood. Knots 

dropped out. This includes knots with 

checks and pith wider than 1/64 inch. 

Open insect damage--Holes, grooves, 

or passages in the wood that are caused 

by the movements of insects. 

Rough veneer.--Veneer that is not 

smoothly cut and will not produce a 

smooth surface when one-quarter of the 

veneer thickness is removed by sanding. 

Roughness may occur as the result of 

natural features of the wood or by 

mismanufacture. 

Splits.--Separations of the wood fibers 

parallel to the grain of the wood. Separations occurring as a result of “checking” 

or “shake” are classified as splits. A 

tight split is one not wider than 1/64 inch. 

An open split is one that is more than 

1/64 inch wide. 

Permissible Characteristics 

The following are characteristics permitted by the grading specifications and 

not considered to be grading defects: 

Distorted grain (burls).--Swirls or 

twists in the grain of the wood, generally 

rounded in outline, and usually resulting 

from overgrowth of dead branch stubs. 

Such areas do not contain a knot or a pith 

center. 

Sound discolorations (stain). - -A sound, 

firm part of the veneer where color 

3 
varying from the natural cast of the or streak. 

veneer is evident and is caused by sap Sound insect damage.--Insect damage 

stain, mineral stain or streak, gum, that is completely and firmly filled with 

water stain, chemical stains such as iron frass and pith. Refer to A (clear) grade 

stain, or oil drips. See A (clear) grade specifications for the only limitation on 

for the only limitations on mineral stain sound insect damage. 

SPECIFICATIONS FOR RECOMMENDED HARDWOOD 

VENEER GRADES 

A (Clear) Grade 

Veneer in this grade must be smooth 

and free of defects. Distorted grain 

(burls) is permitted. Sound discolorations (stain) and sound insect damage are 

permitted with the following limitations: 

mineral stain or streak and soundinsect 

damage may not be over 1/16 inch wide 

by 1/2 inch long, and must be at least 

21 inches from any other mineral stain 

or streak or sound insect damage. 

B (Sound) Grade 

Veneer in this grade must be smooth 

and free of open defects. This grade 

admits distorted grain, sound discolorations, and sound insect damage, as in 

grade A but without limitation of size or 

number. In addition, sound knots up to 

3/4 inch in average diameter, sound gum 

spots, and tight splits are permitted. 

Larger knots and splits, open knots 

and large knot holes, decay, brashness, 

cross breaks, holes, and roughness are 

not permitted. 

C (Utility and Back) Grade 

Veneer in C grade may contain the 

defects of the B grade. In addition, there 

may be open knots, knot holes, holes, or 

open insect damage up to 2 inches in 

maximum diameter for a single hole or a 

group of holes up to 4 inches in aggregate 

diameter in any 12-inch-square area. 

Knots that contain decay are permitted 

if the surrounding wood is sound and the 

knot holes plus the decayed area meet the 

size limitations for open knots or knot 

holes. 

Cross breaks and roughness are permitted if their largest dimension does 

not exceed 2 inches. 

Splits up to 1 inch wide at the widest 

point shall be admitted if they are onefourth or less the length of the veneer 

sheet. Splits 1/2 inch wide at the widest 

point may not be over one-half the veneer 

length. Splits 1/4 inch wide at the widest 

point may be over one-half the veneer 

length. 

Larger knots, splits, holes, cross 

breaks, roughness, open insect damage, 

and decayed areas are not permitted. 

PROCEDURE 

Specific study procedures varied cepts remained constant. Each mill was 

slightly with each mill but overall con- selected on the basis of study objectives, 

4 FPL-9 
end products, and availability of veneer 

logs and species. cent level. 

at each mill for accuracy to the 95 perAll studies started with logs selected 

at the mills and included the range of 

log sizes and quality being peeled. Based 

on the Hardwood Log Grades for Standard 

Lumber, log quality ranged from No. 1 

through No. 3 and poorer. 

Mill practices of log bucking, bolt 

heating, debarking, and veneer peeling 

varied somewhat for each of the four 

studies. The bucking operation at three 

of the mills was performed prior to 

heating the logs, and after heating at the 

fourth mill. At three of the mills the bolts 

or logs were heated in hot water vats, and 

in a steam chamber at the fourth. One mill 

banded bolt ends with steel straps in an 

attempt to reduce end-checking during 

heating. At three mills bolts were debarked after heating. The thickness and 

length of veneer produced varied between 

mills. Thicknesses of 1/28, 1/22, 1/18, 

and 1/16 inch, and spurred lengths of 24, 

36, 75, 86, and 100 inches were produced. 

6 

Veneer Grading 

The veneer from a bolt was graded, 

green and dry, by Forest Products Laboratory personnel using the recommended veneer grades. The grading of 

the green veneer was done ahead of the 

clipper to obtain a theoretical maximum 

grade yield according to the recommended grades for hardwood veneer, 

without the influence of plant clipping. 

This, in effect, required the grader to 

mentally “clip” the veneer and grade 

the resulting pieces. The green veneer 

was not regraded after mill clipping. In 

application of the grades, the minimumusable veneer width is 6 inches with no 

maximum width. Where mill practice 

included actually cutting back dry veneer 

to raise the grade of individual pieces, 

the green veneer graded by the Forest 

Products Laboratory graders was mentally “cut back” in length, 8 to upgrade 

a piece. 

The green veneer was clipped, sorted, 

and dried to a moisture content of 6 to 

10 percent. Each piece of dry veneer was 

graded by a company grader. At three of 

the mills the recommended veneer 

7 

Veneer from each bolt was graded in grades were applied to the sheets of dry 

units about 50 feet wide. The 50-foot veneer after the veneer had been sorted 

size was arbitrarily selected as prelimi- into company grades. Dry-grading at the 

nary investigations indicated that such a fourth mill was not possible. 

sampling unit would be advantageous for 

the type of statistical analysis to be used. Analysis 

It was determined that a minimum number of 110 sampling units would be needed The yields of veneer from each study 

6 only by the physical limitation of a grader in 

Hardwood Log Grades for Standard Lumber. not being able to reach and measure beyond 

Forest Products Lab. Rept. No. 1737. 1953. about 48 inches, without having to use mental 

7 addition. 

Assuming veneer grade did not change, the 8 

maximum width for these studies was limited Veneer length is the spurred length. 

5 
were analyzed separately. The analysis 

approach was to compare the existing 

plant-grading system with the system 

recommended by the Forest Products 

Laboratory. This permitted an evaluation 

of the degree of correlation existing between the quality of veneer segregated 

by the plant system and that segregated 

by the FPL system. Linear regression 

and correlation analysis measured the 

degree of association between the two 

systems. For statistical analysis the 

area of veneer in the company grades 

was the dependent variable, and the independent variable in the FPL grades. 

Automatic computation and analysis 

of data was made from punched data 

processing cards. 

RESULTS AND DISCUSSION 

Grades and Volumes in square feet of veneer is shown by 

studies and FPL grades in table 1. 

A total of 1,094 sample units of green Vermont Study (Yellow Birch).--Results 

veneer (321,703 square feet) were in- of the Vermont yellow birch study were 

cluded in the four studies. Size distribu- based on 138 sampling units of veneer 

tion of the sampling units is shown in containing 46,553 square feet of green 

figure 1. A summary of the distribution veneer. According to the recommended 

Figure 1.--Size distribution of sampling units by 10-foot-width classes. 

M 125 122 

6 FPL-9 
Forest Products Laboratory grades, 33.5 

percent of this green veneer was of grade 

A, 22.2 percent of grade B, and 34.9 percent of grade C quality, while the remaining 9.4 percent was termed residue. 

From this amount of green veneer, 

26,869 square feet of dry usable veneer 

was obtained. The company termed 65.4 

percent of this dry veneer face grade 

and the remainder back grade. The 

study methods did not permit the development of a table of yields by company grades within Forest Products 

Laboratory grades. 

Wisconsin Study (Yellow Birch) .--Results of the Wisconsin yellow birch study 

were based on 360 sampling units of 

veneer containing 110,279 square feet of 

green reeled veneer and 20,029 square 

feet of green round-up veneer. According 

to the recommended grades 85,277 

square feet of the green reeled veneer 

and 17,862 square feet of the green roundup veneer was A, B, and C quality, and 

the remaining 27,169 square feet was 

residue. The Forest Products Laboratory grades segregated this total of 

130,308 square feet of green veneer into 

45.9 percent grade A, 8.2 percent grade 

B, 25.1 percent grade C, and 20.8 percent residue. A total of 78,952 square 

feet of dry usable veneer was obtained. 

Table 1--Yield of total green veneer as segregated 

by Forest Products Laboratory grades 

Study 

Vermont - - 

yellow 

birch 

Wisconsin-- 

yellow 

birch 

Wisconsin-- 

hard maple 

Georgia-- 

red gum 

Totals 

Sampling units 

No. 

138 

3 60 

316 

280 

1,094 

Total 

green 

veneer 

sq. ft. 

46,553 

130 , 308 

137,073 

107,769 

321,703 

Yield (FPL grades) 

A 

Pct. 

33.5 

45.9 

60.1 

27.5 

Pct. 

22.2 

8.2 

17.7 

30.8 

Pct. 

34.9 

25.1 

16.8 

20.1 

Residue 

Pct. 

9.4 

20.8 

5.4 

21.6 

Yield 

(total 

usable 

dry 

veneer) 

sq. ft. 

26,869 

78,952 

26,871 

78 , 295 

210,987 

'Includes an estimated 2,000 square feet of residue green veneer. Actual 

measurements were not possible. 

7 

B C 
The yields by company grades and FPL 

grades are shown in table 2. 

Wisconsin Study (Hard Maple).--Results of the Wisconsin hard maple study 

were based on 316 sampling units of 

veneer that contained 35,073 square feet 

of grades A, B, and C quality veneer. At 

least an additional 2,000 square feet of 

green veneer in the units was residue. 

Actual measurement of this residue could 

not always be made due to the veneer 

being torn and piled from the lathe. The 

37,073 square feet was segregated by the 

FPL grades into 60.1 percent grade A, 

17.7 percent grade B, 16.8 percent grade 

C, and 5.4 percent residue. The plant 

recovered 26,871 square feet of dry 

usable veneer. The yields by company 

grades and FPL grades are shown in 

table 3. 

Georgia Study (Redgum) .--Results of 

the Georgia redgum study were based on 

Total 

Pct. 

61.97 

15.50 

FPL 

grade 

A 

B 

C 

Residue 

Total 

Value 

(Do llars 

per 

1,000 

sq. ft.) 

50.01 

26.34 

280 sampling units of veneer containing 

107,769 square feet of green veneer. 

This veneer was segregated by the FPL 

grades into 27.5 percent grade A, 30.8 

percent grade B, 20.1 percent grade C, 

and 21.6 percent residue. A total of 

78,295 square feet of dry usable veneer 

was obtained. Representative dry yields 

by company grades and FPL grades are 

shown in table 4. 

Table 4 is based on the dry veneer that 

was selected by the company graders for 

cutting back and trimming to raise grade. 

This is approximately one-third (22,934 

square feet) of the total dry veneer from 

this study. The veneer was therefore 

given only one Forest Products Laboratory grade per piece of veneer, i.e., no 

additional cutting back or trimming was 

done by the FPL graders to upgrade a 

piece. 

Table 2.--Yields of dry veneer by Forest Products Laboratory 

grades and company grades. (Wisconsin--yellow 

birch study ) 

(5) 

Select 

reds 

Pct. 

12.06 

1.07 

.27 

13.40 

(6) 

Select 

whites 

Pct. 

10.07 

.35 

.07 

10.49 

Company grade 

(1) 

No. 1 

faces 

Pct. 

33.02 

1.84 

2.33 

37.19 

(2) 

No. 2 

sound 

Pct. 

6.66 

10.83 

9.73 

.04 

27.26 

(3) 

No, 3 

utility 

Pct. 

0.08 

.56 

1.68 

2.32 

(4) 

No. 4 

rejected 

Pct. 

0.08 

.85 

8.06 

.35 

9434 100.00 40.03 

8 FPL-9 

22.14 22.15 

.39 13.31 
Table 3.--Yields of dry veneer by Forest Products 

Laboratory grades and company grades 

(Wisconsin--hard maple study) 

Total 

FPL 

grade 

A 

B 

C 

Total 

per 

1,000 

sq. ft.) 

FPL 

grade 

64.15 

2.52 

100.00 

A 

B 

C 

Residue 

Total 

14.95 

14.28 

18.42 

White 

Pct. 

34.67 

11.53 

.97 

47.17 

Company grade 

Naturals 

Pct. 

0.67 

6.67 

3.81 

11.15 

Centers 

Pct. 

1.58 

11.12 

28.98 

41.68 

Total 

Pct. 

36.92 

29.32 

33.76 

100.00 

Value 

(Dollars 

Per 

1,000 

sq. ft.) 

66.58 

46.13 

26.49 

47.05 

Table 4.--Yields of dry veneer by Forest Products 

Laboratory grades and company grades 

(Georgia--redgum study ) 1 

(1) 

Clear 

finish 

Pct. 

2.46 

1.84 

.68 

.07 

5.05 

(2) 

Paint 

grade 

Pct. 

2.02 

10.33 

4.79 

.23 

17.37 

Company grade 

(3) 

utillty 

grade 

Pct. 

1.94 

11.81 

20.14 

.42 

34.31 

(4) 

Back 

grade 

Pct. 

0.20 

2.73 

38.54 

1.80 

43.27 

6.62 30.21 

26.71 24.22 

1 Percentages are based on about one-third of the study veneer at this 

mill and are expected to be representative of the entire volume 

peeled. 

9 

Pct. 

Value 

(Dollars 
Analysis 

Dependent variable Independent variable Estimating equation Correlation 

(Y) yield in (X) yield in (Y = a + bX) values coefficient 

square feet square feet (r) 

(Company grades) (FPL grades) a b 

Faces A + B 16.92504 0.57297 0.80959** 

Backs C 33.88819 .27854 .51905** 

The regression and correlation values 

for comparison of green grade yields for 

each study are shown in tables 5 to 8. 

These results indicate that the recommended F o r e s t P r o d u c t s L a b o r a t o r y 

hardwood veneer grades, when compared 

(Y) (X) 

Mean Mean 

value value 

Sq. ft. Sq. ft. 

127.27 192.59 

67.43 120.41 

with the plant grades, segregate veneer 

in the green condition into groups that 

reflect the utility of the veneer in the dry 

condition. 

The recommended grades are to be 

applied to the green unclipped veneer 

produced from a bolt. These green yields 

give the most accurate measure of 

(Y) 

Mean 

value 

Table 5.--Regression and correlation values for grade yield comparisons 

(Vermont--yellow birch study) 

(X) 

Mean 

value 

Sq. ft. 

133.95 

59.78 

25.58 

133.95 

59.78 

25.58 

Table 6.--Regression and correlation values for grade yield comparisons 

(Wisconsin--yellow birch study) 

Sq. ft. 

136.06 

33.98 

48.43 

166.05 

29.67 

90.78 

(Y) yield in (X) yield in 

square feet square feet 

(Company grades)- (FPL grades) 

5 + 6 + 1 

2 

3 + 4 

5 + 6 + 1 

2 

3 + 4 

Dry 

A 

B 

C 

Green 

A 

B 

C 

Estimating equation 

(Y = a + bX) values 

5.69 

27.32 

.35 

46.98 

48.05 

11.65 

0.94271 

.95528 

.52091 

.52378 

.39517 

.15340 

Correlation 

coefficient 

(r) 

0.93517** 

.66908** 

.73561** 

.70345** 

.29609** 

.43926** 

1 Company grades are as follows: 5--select reds; 6--select whites; 1--No. 1 faces; 2--No. 2 

sound; 3--No. 3 utility; 4--No. 4 rejected. 

* * 

FPL-9 Denotes significance at 1 percent level. 

a b 

Dependent variable Independent variable 
Table 7.--Regression and correlation values for grade yield comparisons 

(Wisconsin--hard maple study) 

Dependent variable Independent Variable Estimating equation 

(X) yield in 

square feet 

(FPL grades) 

(Y) yield in 

square feet 

(Company grades) 

Correlation (Y) 

coefficient Mean 

(r) value 

White 

(X) 

Mean 

value 

Naturals 

Centers 

0.87222- 40.10 

.48553** 9.49 

.80067** 35.44 

.72245** 40.10 

.37045** 9.49 

.57688** 35.44 

White 

Naturals 

Centers 

31.40 

24.93 

28.71 

70.42 

20.79 

19.78 

Green 

3.89 

3.93 

26.02 

(Y = a + bX) values 

.51425 

.26740 

.47653 

Dependent variable 

(Y) yield in 

square feet 

(Company grades) 1 

1 + 2 

3 

4 

7.12 1.05044 

-0.27 .39133 

12.15 .81128 

Independent variable 

(X) yield in 

square feet 

(FPL grades) 

Green 

A 

B 

C 

26.9128 0.3152 0.4530** 

53.7885 .1438 .2325** 

93.2403 .7043 .5947** 

64.09 117.95 

71.78 125.30 

143.74 71.71 

** Denotes significance at 1 percent level. 

Table 8.--Regression and correlation values for grade yield comparisons 

(Georgia-- red gum study) 

Sq. ft. Sq. ft. 

1 Company grades are as follows: 1--clear finish; 2--paint grade; 3--utility grade; 4--back 

grade. 

** Denotes significance at 1 percent level. 

veneer bolt quality or potential yield. 

The grades can, of course, be used to 

grade dry veneer, but it must be recognized that the plant clipping pattern will 

affect the yield of veneer from a bolt or 

The regression and correlation values 

for comparisons of total green Forest 

log. 

Products Laboratory grade yields with 

the mill recovery of total dry veneer are 

shown for the four studies in table 9. The 

correlations are significant and indicate 

that green veneer yields can be used to 

estimate total dry recovery. 

The estimating equations in tables 5 to 

9 apply only to a mill and its conditions 

11 

Sq. ft. Sq. ft. 

a b 

A 

B 

C 

Dry 

A 

B 

C 

Estimating equation 

a b 

(Y = a + bX) values 

Correlation 

coefficient 

(r) 

(Y) 

Mean 

value 

(X) 

Mean 

value 
at the time of the study. Any change in practices would undoubtedly change the 

veneer grading or mill manufacturing equations. 

Table 9.--Regression and correlation values for comparison of total yields 

Dependent variable 

(Y) total dry veneer yields 

(Company grades) 

Vermont--yellow birch 

Faces and backs 

Wisconsin--yellow birch 1 

5 + 6 + 1 + 2 + 3 + 4 

Wiscons in--hard maple 

Whites and naturals and centers 

Georgia - - red gum 2 

1 + 2 + 3 + 4 

Independent variable 

(X) total green 

veneer yields 

(FPL grades) 

A + B + C 

A + B + C 

A + B + C 

A + B + C 

Estimating equation 

(Y = a + bX) values 

61.08 0.55283 

21.82 1.0236 

Correlation 

coefficient 

(r) 

0.56886** 

0.74421** 

0.88580** 

0.9441** 

(Y) 

Mean 

value 

Sq. ft. 

194.70 

219.38 

85.03 

279.62 

(X) 

Mean 

value 

sq. ft. 

313 

286.50 

110.99 

251.84 

Number 

of 

samples 

(n) 

138 

3 60 

316 

280 

Denotes significance at 1 percent level. ** 

1 Grade numbers signify the following: 5--select reds; 6--select whites; 1--No. 1 sound; 2-- No. 2 sound; 3 -- NO. 3 

u t i l i t y ; 4 - - N o . 4 rejected. (Wisconsin--yellow birch study.) 

(Georgia--redgum study.) 

2 Grade numbers signify the following: 1--clear finish; 2--paint grade; 3 -- utility grade; 4--back grade. 

CONCLUSIONS 

From the results of these four studies grades and plant grades with which they 

it is concluded that the Forest Products were compared. For developing veneer 

Laboratory hardwood veneer grades can log and bolt grades, the Forest Products 

be used to develop hardwood veneer log Laboratory grades should be applied to 

grades. This is shown by the significant the green unclipped veneer produced 

relationship between the recommended from a bolt. 

12 2.-12 

a b 

56.60 0.44123 

16.50 0.62062 

• • •