producing, usable crops of wood (usually sawtim- 

 ber), (b) economically available now or prospec- 

 tively, and (f) not withdrawn from timber utiliza- 

 tion. 



Area reserved from commercial timber use.— 

 Forest land withdrawn from timber utilization 

 throus;h statute, ordinance, or administrative order, 

 hut which otherwise qualifies as commercial forest 

 land. 



Forest Types 



Pine.— Stands in which pine species comprise at 

 least 60 percent of the dominant and codominant 

 trees. 



REDCEDAR-HARD^vooD.— Stands in ^vhich redcedar 

 comprises at least 20 percent of the dominant and 

 codominant trees. 



Oak-pine.— Stands in which 40 percent or more of 

 the species is hardwood, usually upland oaks, but 

 in which southern pines make up 20-60 percent. 



Oak-hickory.— Hardwood stands in which oaks 

 and hickories comprise at least 60 percent of the 

 dominant and codominant trees. 



White oak.— Hardwood stands in which white 

 oak {Quercus alba) comprises at least 60 percent of 

 the dominant and codominant trees. 



Beech-maple.— Hardwood stands in which beech 

 and sugar maple comprise at least 60 percent of the 

 dominant and codominant trees. 



Mixed hardwoods.— Stands of mixed hardwood 

 species not qualifying for other hardwood types. 

 Principal species include yellow-poplar, elm, ma- 

 ple, basswood, ash, beech, hemlock, and black locust 

 in mixture with oaks and hickories. 



Bottom-land hardwoods.— Stands on the alluvial 

 bottoms of rivers and streams. The principal species 

 include sycamore, willow, elm, blackgum, sweetgum, 

 soft maples, oaks, hickory, cottonwood, and cypress. 



Tree Classes 



Sawtimber tree.— a live softwood (coniferous) 

 tree at least 9 inches d.b.h. or live hardwood (broad- 

 leaf) tree at least 11 inches d.b.h. of commercial spe- 

 cies, with a sound butt log at least 8 feet long, or with 

 at least half of the gioss volume of the tree in sound 

 material. 



Poletimber trees.— Trees 5 inches d.b.h. and 

 larger of commercial species that do not meet the 



specifications for sawtimber trees but do meet re- 

 gional specifications of species, soundness, and free- 

 dom from defect. 



Seedling and sapling trees.— Trees of commer- 

 cial species less than 5 inches in diameter at breast 

 height, btit not less than 1 inch. 



Cull trees.— Live trees of sawtimber or poletim- 

 ber size that are unmerchantable for sa^vlogs now 

 or prospectively because of defect, rot, or species, 

 such as sumac, redbud, and w'inged elnr. 



Rotten cull trees.— Live trees of sa^vtimber 

 or poletimber size that fail to ineet regional 

 specifications of proportion of sound volume 

 to total volume. 



Sound cull trees.— Live trees of sawtimber 

 or poletimber size that meet regional specifica- 

 tions of freedom from rot but will not make at 

 least one merchantable sa'wlog now or prospec- 

 tively according to regional specifications be- 

 cause of roughness, poor form, or species. 



Volume Estimates 



Sawtimber volume.— Net volume in board feet, 

 International 14 -inch rule, of live sawtimber trees 

 to a minimum top diameter inside bark of 6 inches 

 for softwoods and 8 inches for hardwoods. 



Growing stock.— Net volume in cubic feet of live 

 sawtimber trees and live poletimber trees from 

 stump to a minimum 4.0-inch top (of central stem) 

 inside bark. (Note: In the statistics presented in this 

 report, the volume of upper stems of hardwoods is 

 included with limbs rather than with the sawtimber 

 \olume.) 



Total volume.— The vohmie of sound wood in- 

 side bark in both sound and cull living trees 5 

 inches d.b.h. and larger, from the stump to a mini- 

 miun top diameter of 4 inches inside bark, expressed 

 in cubic feet. It includes the upper stems of soft- 

 wood trees and the upper steins and limbs of hard- 

 woods. 



Stocki7is: Classes 



Stocking.— Stocking is the extent to which grow- 

 ing space is effectively utilized by present or poten- 

 tial growing-stock trees of commercial species. Three 

 degiees of stocking were recognized: 



Good.— At least 70 percent crown cover. 



Fair.— ¥rom 40 to 70 percent crown cover. 



Poor.— Less than 40 percent crown cover. 



38 



Forest Resource Report No. 7, U. S. Department of .Agriculture 



