THE NORTHERN HARDWOOD FOREST. 



63 



Table 39. — Per cent of wood in -piles of red maple cordwood, based on 9 piles of from 

 2 to 4 cord feet each, Harvard Forest, Petersham, Mass., 1910-11. 



Diameter, 





Diameter, 





Diameter, 





Diameter, 





breast- 



Per cent 



breast- 



Per cent 



breast- 



Per cent 



breast- 



Per cent 



high of 



of wood 



high of 



of wood 



high of 



of wood 



high of 



of wood 



trees cut 



in piles. 



trees cut 



in piles. 



trees cut 



in piles. 



trees cut 



in piles. 



and piled. 





and piled. 





and piled. 





and piled. 





Inches. 





Inches. 





Inches. 





Inches. 





3 



52.5 



7 



58.0 



11 



68.0 



15 



74.0 



4 



53.6 



8 



60.2 



12 



70.0 



16 



74.6 



5 



54.9 



9 



62.8 



13 



71.5 



17 



75.0 



6 



56.2 



10 



65.5 



14 



73.0 







GRADED LOG SCALE TABLES. 



Tables 40, 41, 42, are taken, with slight modification in arrangement, from "Graded 

 volume tables for Vermont hardwoods," by Irving W. Bailey and Philip C. Heald, 

 Forestry Quarterly, Volume XII, No. 1, pages 5-23. These give the contents in 

 graded lumber of a large number of logs of yellow birch, hard maple, and beech, from 

 hardwood stands on lower slopes and foothills of the Green Mountains in southern 

 Vermont. The logs were run through a single-action band saw cutting a one-eighth 

 inch kerf, and the lumber from each was graded according to the grading rules of the 

 Northern Hardwood Lumber Association, the results being averaged by a curve. 

 The lumber was mostly 1 inch stock, sawed 1| inches thick to allow for shrinkage. 

 The mill crew were men of average skill, experienced in hardwood mills in other 

 regions. 



The merchantable length of the trees was seldom over 32 feet; practically no logs 

 were taken above the first branches. The percentage of 1, 2, and 3 log trees was as 

 follows: 



l-log trees 

 2-log trees 

 3-log trees 



Birch. Maple. Beech 



18 



Nearly one-half of the logs cut were defective or abnormal in some particular. 1 The 

 following defects were noted in regard to their influence in decreasing the volumes of 

 the logs: Butt defects, top defects, crook, sweep, knots, seams, shake, miscellaneous. 

 For yellow birch a comparison was made of the contents of nondefective butt logs, non- 

 defective top logs, and the average o-f all logs. This showed that the difference in 

 volume due both to defect and position in the tree was negligible for logs under 12 

 inches in diameter at the small end, while for logs 12 inches and over in diameter it 

 amounted to about 9 per cent of the volume of the sound butt logs. It was less than 

 6 per cent for logs from 12 to 16 inches in diameter, and a little less than 11 per cent 

 for 21 to 24 inch logs. The difference due to position in the tree between sound normal 

 top and butt logs varied from about 3 per cent of the volume of the 12 to 16 inch butt 

 logs to about 10 per cent of the 21 to 24 inch butt logs. 



In the table for yellow birch it will be noted that the 10-foot logs show a greater pro- 

 portion of the poorer grades than do the longer logs. This is particularly noticeable 

 in the No. 1 common red and the No. 2 common grades, and is due especially to the 

 fact that the majority of the 10-foot logs were top logs and hence knotty and of inferior 

 quality. 



While they can be applied with substantial accuracy only to conditions similar to 

 those Under which they were made, these tables may perhaps be used in other regions 



1 The percentages of defective logs were: Birch 43 per cent, maple 45 per cent, beech 51 per cent. 



