APPENDIX — CRITERIA FOR RATING PRODUCTIVITY 



681 



Table 90. — Percentage oj mean annual growth at culmination attained at various sizes or ages, by jorest 

 type group and size class oj products cut, New England and Middle Atlantic Regions 





Spruce-fir type group 



Maple-beech-birch type 



Stump diameter inside bark (inches) 



Sp^uce and hardwoods 



Balsam fir, 

 all products 



group, all hardwoods 





Sawtimber 



Ccrdwood 



Sawtimber 



Cordwood 



6 - - _-_ - 



Percent 



Percent 



Percent 



40 

 60 

 80 

 90 

 100 



Percent 



Percent 



7 - __ - - 











8 - __. . ._ ___ _ _ - 





40 

 60 

 75 



90 

 100 





40 



9 







63 



10 . _-. _ __ __ _ ... 



40 



50 

 60 

 70 

 80 

 88 



94 



98 



100 



40 



50 

 65 



80 



11 .--.-- 



90 



12 - 





100 



13 - ----- --- --- -- - 







14 - - - - - 







80 





15 ...-_- 









16 - - 







90 





17 ------ 









18 - - ----------- 







95 

 100 





20 - - - - -- - 





















White 



pine type,' 



red and 



white 



pines, all 



products 



Oak-hickory type group 



Loblolly- 

 pine typ 



shortleaf 

 e group, 



Age (years) 



Yellow-poplar and 

 sweetgum 



Oak and other 

 hardwoods 



southern pines and 

 southern pine-hard- 

 wood type 





Saw- 

 timber 



Cord- 

 wood 



Saw- 

 timber 



Cord- 

 wood 



Saw- 

 timber 



Cord- 

 wood 



15 



Percent 



Percent 



Percent 

 40 

 60 

 75 

 84 



90 

 95 



Percent 



Percent 



Percent 



Percent 



20 













60 



25 -- ----- 









40 

 60 



72 

 82 

 92 

 96 



100 



30 

 43 



63 



80 



92 



100 



80 



30 - -- -- 



40 



40 

 60 



95 



35 





98 



40 - - - 



65 



100 



45 - - 





50 - - -- 



80 



92 



98 



100 



80 



90 



95 



100 



ioo 



40 



62 



80 



90 



100 





60 





70 









80 











90 - 

























Of till' white-red-jack pine type group. 



Standards for determining prospective stocking 

 based on proximity to margin of groups, strips, 

 or stands of seed-bearing trees were as follows: 



Slocking 



expected 



Distance from seed source (chams) : (percent) 



0-2 100 



2-4 80 



4-6 60 



6-8 40 



8-10 20 



10-f 



Swamp black spruce-tamarack type. — Prospective 

 stocking was considered for any cutting since 

 January 1, 1B47, in the black spruce subtype, butfor 

 the tamarack subtj'pe prospective stocking was 

 considered only if cutting was done less than 5 

 years prior to examination. 



Individual trees left standing on recent cutovers 

 were not recognized as seed sources because of 

 their susceptibility to windthrow. The following 

 standard was used for determining prospective 



