United States 

Department of 

Agriculture Photographic Guide of 

Forest Service Selected External Defect 

Northeastern Forest 

Experiment Station Indicators and Associated 

Research Paper 

NE-560 Internal Defects in 

1985 Black Cherry 

Everette D. Rast 

John A. Beaton 
The Authors 

Everette D. Rast, research forest products technologist, received a B.S. 

degree in forestry from the University of Missouri in 1960 and an M.S. degree in agricultural economics from Ohio State University in 1970. He 

joined the Forest Service in 1960 as a forester on the Mendocino National 

Forest and transferred to the Northeastern Forest Experiment Station, 

Delaware, Ohio, in 1966. 

John A. Beaton, forestry technician, received his Certificate as a Forest 

Technician from Lake City Junior College and Forest Ranger School, Lake 

City, Florida in 1964. He joined the Forest Service in October 1964 as a 

Forestry Aid at the Forest Insect and Disease Lab, Delaware, Ohio. In 

November 1976, he transferred to Project 1351, Northeastern Forest Experiment Station, Delaware, Ohio, as a forestry technician. 

Manuscript received for publication 3 October 1984 

Abstract 

To properly classify or grade logs or trees, one must be able to correctly 

identify defect indicators and assess the effect of the underlying defect on 

possible end products. This guide aids the individual in identifying the surface defect indicator and also shows the progressive stages of the defect 

throughout its development for black cherry. It illustrates and describes 

seven types of external defect indicators and associated defects that are 

particularly difficult to evaluate. 
Introduction 

This photographic guide on black 

cherry is the second in a series to 

aid in the understanding of the relationship between exterior defect 

indicators and the underlying defect. This study, like the previous 

one on northern red oak (Rast 19821, 

was conducted at a veneer slicing 

plant which enabled us to photograph defect characteristics at 

intervals of 1/32 of an inch (one 

sheet of veneer). 

Procedure 

The only procedural change from 

the 1982 study was that these logs 

were selected and photographed in 

the woods. They came from an 

almost pure stand of black cherry in 

north central Pennsylvania. The 

defect indicators reported in this 

publication are gum lesion; suppressed bud; suppressed bud cluster; 

light, medium, and heavy bark distortions; sound and unsound wounds; 

seam; and burl. 

Figure 1.-Gum lesions and associated internal defects. 

Discussion of Defects 

We feel that the selected defect 

indicators are often difficult to 

evaluate in terms of their effect on 

end-product quality. Graders normally have little difficulty recognizing and evaluating the obvious 

grading defects such as limbs, holes, 

forks, bulges, or butt scars. 

The descriptions listed below the 

photo of the defect indicator (see 

Fig. 1) describe its size in terms of 

Defect size ...................... 3 x 2 inches 

Log diameter ..................... 18.6 inches 

Log diameter at defect ............ 19.9 inches 

Flitch thickness at defect ........... 8.9 inches 

Slab + round-up thickness at defect ... 1.3 inches 

Log position ........................ butt log 

Depth belowLog surface 

1.3 inches 

First sheet of veneer 

0.0 inches 
length (along the grain), width 

(across the grain), and height (above 

the normal bark surface); log diameter, inside-the-bark small end; 

log diameter, inside-the-bark at the 

defect; flitch thickness at the defect; slab plus round-up thickness at 

the defect; and log position. The 

information listed under the interior 

defect (see Fig. 1) indicates distance below the log surface (insidethe-bark) as well as the distance 

from the first slice of veneer to 

that particular photographed defect. 

The last photograph in each defect 

series also lists cumulative veneer 

thickness, which is the distance 

from the initial slice of useable 

veneer to the last slice of veneer. 

A point of interest is that the 

National Hardwood Lumber Association grading rules on black cherry 

allows small knots or their equivalent not exceeding 1/8 inch in diameter in the cuttings (NHLA 1982). 

Gum Lesion 

Gum lesions (Fig. 1) appear as 

slightly darker than normal bark to 

an almost black area on the already 

reddish bark of black cherry. Clear 

to amber-colored exudate is almost 

always present on the bark surface. 

Gummosis, the production of this 

exudate, can result from many 

causes such as peach tree borer, 

wounding, bacteria, fungi or even 

poorly aerated soils (Boyce 1948, 

Esau 1965). If only gum exudate is 

present, the defect depth is seldom 

great, but if the bark appears discolored, the gum and some grain 

distortion usually extend into the 

highquality wood. 

Depth below- Depth belowLog surface 

1.8 inches 

First sheet of veneer 

0.5 inches 

Log surface 

2.3 inches 

First sheet of veneer 

1.0 inches 
Depth below- Depth belowLog surface 

2.8 inches 

First sheet of veneer Log surface 

1.5 inches 3.3 inches 

First sheet of veneer 

2.0 inches 

Depth belowLog surface 

3.6 inches 

First sheet of veneer 

2.2 inches 

Total veneer thickness-6.9 inches 
Suppressed buds (commonly re- these buds can sprout suddenly after these buds. Each of the bud traces 

ferred to as adventitious buds or a thinning, or when attacked by goes from the bark to the pith, with 

dormant buds) can persist for many insects or infected by disease. Fig- little or no exterior indication that 

years as just a bud trace (Kormanik ure 3 shows a cross-section of a log they existed. 

1969), yet never become an epi- (17.5 inches inside-the-bark) that 

cormic branch (Fig. 2). However, was sawn right through several of 

Figure 2.-Suppressed buds and associated internal de 

Defect size .............. 112 x 112 x 112 inch 

Log diameter ..................... 18.3 inches 

Log diameter at defect ............ 18.9 inches 

Flitch thickness at defect ........... 8.7 inches 

Slab + round-up thickness at defect ... 1.5 inches 

.Log position ........................ butt log 

Depth belowLog surface 

1.5 inches 

First sheet of veneer 

0.0 inches 
Depth below- Depth belowLog surface First sheet of veneer Log surface First sheet of veneer 

4.5 inches 3.0 inches 6.5 inches 5.0 inches 

Figure 3.-Cross-sectional view of log showing 

bud traces of suppressed buds. 

Depth belowLog surface 

8.0 inches 

First sheet of veneer 

6.5 inches 

Total veneer thickness-6.7 inches I 
Suppressed Bud Cluster 

The major differences between a that can be seen in the wood. Figsingle bud (or only 2 or 3 buds) and a ure 4 shows both the concentric 

bud cluster are the size of the de- rings around the defect indicator on 

fect indicator, evidence of concen- the bark surface and the many adtric rings around the indicator, and ventitious knots in the underlying 

the clustering of numerous knots wood. 

Figure 4.-Suppressed bud cluster 

and associated internal defects. 

Defect size ............... 1 112 x 1 x 1 inches Depth belowLog diameter ..................... 15.6 inches 

Log diameter at defect ............ 15.8 inches Log surface First sheet of veneer 

Flitch thickness at defect ........... 6.6 inches 2.4 inches 0.0 inches 

Slab + round-up thickness at defect ... 2.4 inches 

Log position ....................... upper log 
Depth below- Depth belowLog surface 

4.4 inches 

First sheet of veneer 

2.0 inches 

Log surface 

5.4 inches 

First sheet of veneer 

3.0 inches 

Depth belowLog surface 

5.9 inches 

First sheet of veneer 

3.5 inches 

Total veneer thickness-3.7 inches 
Bark Distortions 

Bark distortions-those that are 

flush with the bark--are su6divided 

into three categories: light, medium, and heavy bark distortions. A 

light bark distortion (Fig. 5) shows 

only a slight amount of curvature in 

the surrounding bark plates, and the 

bark pattern shows only slight variance from normal. Because of these 

features, light bark distortions are 

very inconspicuous and often overlooked. Medium bark distortions 

(Fig. 6) show more signs of the conFigure 5.-Light bark distortion and 

associated internal defects. 

centric circles, but they are broken 

by flat bark plates or regular bark 

patterns. Also, there is usually a 

well-defined break in the bark pattern in the center of the defect 

indicator. Heavy bark distortions 

(Fig. 7) are normally identified by 

the characteristic pattern of concentric circles encompassing the 

defect indicator. Often in black 

cherry these rings are concentrated 

on one side of the defect indicator. 

All bark distortions will result in 

some product degrade, but the amount of degrade kill decrease as 

the depth to the initial defect below 

the log surface increases. For these 

bark distortions, if we adjusted for 

log diameter, then the depth below 

the log surface to the first sign of 

the defect would be 5-112 inches, 3- 

1/2 inches, and less than 112 inch, 

respectively. 

Defect size ...................... 2 x 2 inches 

Log diameter ..................... 17.5 inches 

Log diameter at defect ............ 18.1 inches 

Flitch thickness at defect ........... 7.2 inches 

Slab + round-up thickness at defect ... 2.1 inches 

Log position ....................... upper log 

Depth belowLog surface First sheet of veneer 

2.6 inches 0.5 inches 
Depth below- , Depth belowLog surface 

4.1 inches 

First sheet of veneer 

2.0 inches 

Log surface 

4.6 inches 

First sheet of veneer 

2.5 inches 

Depth below- Depth belowLog surface 

6.6 inches 

First sheet of veneer 

4.5 inches 

i Log surface ~ First sheet of veneer 

7.3 inches ~ 5.2 inches 

! 

Total veneer thdkness--5.2 inches 
Figure 6.-Medium bark distortions and associated 

internal defects. (Both are medium bark 

'. distortions-data on lower one). 

.- 

Defect size .................. 1 112 x 3 inches 

Log diameter ..................... 20.2 inches 

Log diameter at defect ............ 20.4 inches 

Flitch thickness at defect ........... 9.4 inches 

Slab + round-up thickness at defect ... 1.3 inches 

Log position ........................ butt log 

,Depth belowLog surface 

3.8 inches 

First sheet of veneer 

2.5 inches 

Depth below- Depth belowLog surface 

4.3 inches 

10 

First sheet of veneer 

3.0 inches 

Log surface 

4.8 inches 

First sheet of veneer 

3.5 inches 
Depth below- Depth belowLog surface 

5.8 inches 

First sheet of veneer 

4.5 inches 

Log surface 

6.3 inches 

Depth belowLog surface First sheet of veneer 

6.8 inches 5.5 inches 

Total veneer thickness-7.0 inches 

First sheet of veneer 

5.0 inches 
Figure '/.-Heavy bark distortions and associated 

:internal defects. (Both are heavy bark 

distortions--data on lower one.) 

Defect size .................. 1 1/2 x 2 inches Depth below-- 

Log diameter ..................... 20.6 inches 

Log diameter at defect ............ 21.1 inches Log surface First sheet of veneer 

Flitch thickness at defect .......... 10.5 inches 0.5 inches 0.0 inches 

Slab + round-up thickness at defect ... 0.5 inches 

Log position ........................ butt log 

Depth below- Depth belowLog surface 

1.5 inches 

First sheet of veneer Log surf ace 

1.0 inches 2.5 inches 

First sheet of veneer 

2.0 inches 
Depth below- Depth belowLog surface 

3.2 inches 

First sheet of veneer 

2.7 inches 

Log surface 

4.5 inches 

First sheet of veneer 

4.0 inches 

Total veneer thickness-8.2 inches 
Wounds fall into two categories: 

sound and unsound. Sound wounds 

may or may not be degraders depending on their age and depth. If a 

wound is recent and will be slabbed 

off during sawing, or deep and likely 

to be contained in the heart center 

of the log, then it results in very 

little degrade. Figure 8 shows a 

sound wound that did not slab off, 

but would not be a degrader based 

on USDA Forest Service grades for 

factory lumber logs (Rast et al. 

Figure 8.--Overgrown sound wound 

and associated internal defects. 

1973) since its maximum depth in 

the logs is only 2.5 inches (15 percent of the log diameter is 2.7). But 

for veneer logs, this defect is a 

degrader since it affects the first 40 

sheets of veneer. The surrounding 

bark plates show a distinct break 

from the callus tissue over the 

wound, but some breaks showing 

across the wound callus itself are 

characteristic of this type of wound. 

Defect size .................. 3 112 x 3 inches 

Log diameter ..................... 17.3 inches 

Log diameter at defect ............ 17.7 inches 

Flitch thickness at defect ........... 8.5 inches 

Slab + round-up thickness at defect ... 1.3 inches 

Log position ........................ butt log 

Depth belowLog surface First sheet of veneer 

1.3 inches 0.0 inches 
Depth below- Depth belowLog surface First sheet of veneer Log surface First sheet of veneer 

1.5 inches 0.2 inches 1.8 inches 0.5 inches 

Depth belowLog surface 

2.2 inches 

First sheet of veneer 

0.9 inches 

- Depth belowLog surface First sheet of veneer 

I 2.5 inches 1.2 inches 

i Total veneer thickness-5.4 inches: 
Wounds that develop callus tissue 

above the,normal curvature of the 

log surface (height) normally have 

rot associated with them. The size 

(8 x 4 inches) and the height (1 inch) 

of the unsound wound shown in Figure 9 are good indicators of the 

major degrade caused by this type 

of defect. In the last defect photos, 

you can see that this wound 

occurred over an overgrown knot. 

Seams 

Overgrown seams, one of the 

exterior indicators of radial shakes, 

are serious degraders in logs and 

trees. A common misconception is 

that seams are caused by frost, but 

most often they are initiated by 

wounds or limb stubs (Butin 1981; 

Shigo 1969). However, frost is one 

of the major factors in maintaining 

the stress that causes the seams to 

persist for many years. Seams with 

a line of callus and a depressed area 

(Fig. 10) normally have encased bark 

that is evidenced as a hole in sliced 

veneer. This type of defect is serious in logs used to produce lumber 

or veneer. 

Figure 9.-Overgrown unsound wound 

and associated internal defects. 

Defect size .................. 8 x 4 x 1 inches 

Log diameter ..................... 15.1 inches 

Log diameter at defect ............ 15.4 inches 

Flitch thickness at defect ........... 6.8 inches 

Slab + round-up thickness at defect ... 1.0 inches 

Log position ........................ butt log 

Depth belowLog surface 

1.0 inches 

First sheet of veneer 

0.0 inches 
Depth belowLog surface First sheet of veneer 

1.2 inches 0.2 inches 

Depth belowLog surface 

1.5 inches 

First sheet of veneer 

0.5 inches 

Depth below- Depth belowLog surface 

2.0 inches 

First sheet of veneer 

1.0 inches 

Log surface 

2.5 inches 

First sheet of veneer 

1.5 inches 
Depth below- Depth belowLog surface 

3.0 inches 

First sheet of veneer 

2.0 inches 

Log surface 

4.0 inches 

First sheet of veneer 

3.0 inches 

Depth belowLog surface First sheet of veneer 

4.5 inches 3.5 inches 

Depth belowLog surface 

5.0 inches 

First sheet of veneer 

4.0 inches 

Total veneer thickness-4.9 inches 
Figure 10.-Overgrown seam and associated 

internal defects. 

Defect size ..................... 14 x 2 inches 

Log diameter ..................... 17.2 inches 

Log diameter at defect ............ 17.3 inches 

Flitch thickness at defect ........... 7.3 inches 

Slab + round-up thickness at defect ... 2.8 inches 

Log position ........................ butt log 

Depth belowLog surface 

2.8 inches 

- - - - - - - 

First sheet of veneer 

0.0 inches 

Depth below- Depth belowLog surface 

3.8 inches 

First sheet of veneer 

1.0 inches 

Log surface 

4.0 inches 

First sheet of veneer 

1.2 inches 
Depth below- , Depth belowLog surface First sheet of veneer Log surface First sheet of veneer 

4.1 inches 1.3 inches 4.2 inches 1.4 inches 

Total veneer thickness-3.7 inches 

Figure 11.-Burl and associated internal defects. 

Burls are the surface indicators of 

distorted grain, and often they contain ingrown bark, rot, and epicormic knots. Figure 11 shows a 

typical burl on black cherry with a 

small amount of ingrown bark. 

Since this burl occurred less than 

one foot above the stump, more 

than 2 inches was slabbed off due to 

butt swell, yet the bark and distorted grain are still evident. 

Defect size ............... 3 x 3 x 1 112 inches 

Log diameter ..................... 18.2 inches 

Log diameter at defect ............ 19.2 inches 

Flitch thickness at defect ........... 7.8 inches 

Slab + round-up thickness at defect ... 3.1 inches 

Log position ........................ butt log 
Depth below- - 

Log surface First sheet of veneer 

3.1 inches 0.0 inches 

Depth belowLog surface First sheet of veneer 

4.1 inches 1.0 inches 

Depth below-- 

Log surface 

3.6 inches 

First sheet of veneer 

0.5 inches 

Depth belowLog surface 

4.6 inches 

First sheet of veneer 

1.5 inches 

Total veneer thickness-4.8 inches 
Literature Cited 

Boyce, John S. Forest pathology. 

New York: McGraw-Hill Book 

Co., Inc; 1948. 550 p. 

Butin, Heinz; Shigo, Alex L. Radial 

shakes and nfrost cracks" in living 

trees. Res. Pap. NE-478. 

Broomall, PA: U.S. Department 

of Agriculture, Forest Service, 

Northeastern Forest Experiment 

Station; 1981. 21 p. 

Esau, Katherine. Plant anatomy. 

New York: John Wiley & Sons; 

1965: 767 p. 

Kormanik, Paul P.; Brown, Claud L, 

Origin and development of epicormic branches in sweetgum. 

Res. Pap. SE-54. Asheville, NC: 

U.S. Department of Agriculture, 

Forest Service, Southeastern 

Forest Experiment Station; 1969. 

17 p. 

National Hardwood Lumber Association. Rules for the measurement 

and inspection of hardwood and 

cypress. Memphis, TN: National 

Hardwood Lumber Association; 

1982. 115 p. 

Rast, Everette D. Photographie 

guide of selected external defect 

indicators and associated internal 

defects in Northern Red Oak. 

Res. Pap. NE-511. Broomall, PA: 

U.S. Department of Agriculture, 

Forest Service, Northeastern 

Forest Experiment Station; 1982. 

20 p. 

Rast, Everette D.; Sonderman, 

David L.; Gammon, Glenn L. A 

guide to hardwood log grading. 

Gen. Tech. Rep. NE-1. Upper 

Darby, PA: U.S. Department of 

Agriculture, Forest Service, 

Northeastern Forest Experiment 

Station; 1973. 32 p. 

Shigo, Alex L.; Larson, Edwin vH. 

A photo guide to the patterns of 

discoloration and decay in living 

northern hardwood trees. Res. 

Pap. NE-127. Upper Darby, PA: 

U.S. Department of Agriculture, 

Forest Service, Northeastern 

Forest Experiment Station; 1969. 

100 p. 

Acknowledgments 

The authors wish to thank the 

Weyerhaeuser Cod, Jefferson, Pa., 

and the Hammermill Paper Co., 

Coudersport, Pa., for their help and 

cooperation during this study. 
Rast, Everette D.; Beaton, John A. Photographic guide to selected 

external defect indicators and associated internal defects in black 

cherry. Res. Pap. NE-560. Broomall, PA: U.S. Department of 

Agriculture, Forest Service, Northeastern Forest Experiment Station; 

1985. 22 p. 

To properly classify or grade logs or trees, one must be able to correctly 

identify defect indicators and assess the effect of the underlying defect on 

possible end products. This guide aids the individual in identifying the surface defect indicator and also shows the progressive stages of the defect 

throughout its development for black cherry. It illustrates and describes 

seven types of external defect indicators and associated defects that are 

particularly difficult to evaluate. 

ODC 852.1/.12/.13/.17/.19--(084.121) 

Keywords: Defect identification; photo guide; black cherry; quality 

assessment. 

*U. S. GOVERNMENT PRINTING OFFICE:~~B~-~~B-~~~:~OO~~ 
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. 

0 Durham, New Hampshire, in cooperation with the University of 

New Hampshire. 

0 Hamden, Connecticut, in cooperation with Yale University, 

0 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. 

0 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. 

0 Warren, Pennsylvania.