of clear bole and 25 percent of their merchantable 

 length clear of limbs and knots in sections not less 

 than 8 feet in length. As with hardwoods, the pro- 

 portion of better-grade material is greatest in the 

 larger diameter classes. Grade 1 and 2 trees make 

 up 45 percent of the volume in trees 20 inches d. b. h. 

 and larger, 38 percent in 14- to 18-inch trees, and 24 

 percent in 10- and 12-inch trees. 



Sawtimber areas were also classified on the basis of 

 stand quality. Stands classed as fair or better included 

 at least four grade 2 or better hardwood sawlogs or 

 softwood trees per acre. Although this specification 

 is rather lenient, it serves to segregate stands which 

 contain some volume in grades best suited to indus- 

 trial uses, and which are most likely to be logged 

 first. In hardwood types two-fifths of the sawtimber 

 acreage is in fair or better stands; in softwood types, 

 one-third. 



Stand-Size Classes 



Most of Tennessee's forest acreage is in stands below 

 sawtimber size (fig. 20). Only 24 percent of the 

 commercial forest is in sawtimber stands — that is, 

 having a net volume of at least 1,500 board -feet per 

 acre. In west Tennessee sawtimber stands occupy at 

 least one-third of the commercial forest. In the east 

 and Plateau regions they make up 25 percent and in 

 the 2 central regions some 17 percent. To insure a 

 maximum yield of merchantable timber from year to 

 year, a far greater proportion of sawtimber area is 

 needed in all regions. 



The bottom-land hardwood type, with 41 percent of 

 its area in sawtimber, is the most favorably balanced 

 in stand size. The cedar type is most heavily weighted 



to small stands, only 3 percent of its area being saw- 

 timber. Sawtimber distributions of the southern 

 yellow pine type and the upland hardwood type 

 approximate the State average, 25 and 23 percent 

 respectively. 



Stands in which the trees are mostly below sawlog 

 size occupy 9.4 million acres. The largest part of 

 this acreage, 61 percent of the commercial forest, is 

 in poletimber stands, which predominate in all 

 regions. The remaining acreage, about 15 percent, 

 is chiefly in seedling and sapling stands occupying 

 the newer abandoned fields or areas that have re- 

 cently been heavily cut or severely burned. The 

 type of management applied to this extensive under- 

 sawlog-size acreage will largely determine the future 

 productivity of the forest. Most poletimber stands 

 are well stocked with commercial species and will 

 soon become sawtimber stands if given adequate pro- 

 tection from fire and premature cutting. Many 

 seedling and sapling areas have sufficient reproduc- 

 tion of seedling or sprout origin to develop eventually 

 into merchantable stands, but protection from fire 

 and grazing is a primary requirement. 



Tree Stocking 



Fifty-eight percent of the commercial forest in 

 Tennessee is well stocked — that is, has enough sound, 

 well-formed trees of any size or combination of sizes 

 (including established seedlings) to take full advantage 

 of the timber-growing potentialities of the soil (fig. 

 21). Thirty-three percent is medium stocked, having 

 40-69 percent of the number of trees required for 

 full stocking. About 8 percent is poorly stocked and 

 only 1 percent is nonstocked (less than 10 percent of 

 full stocking). 



LARGE 

 SAWTIMBER 



SMALL 

 SAWTIMBER 



CORDWOOD 



SEEDLING 

 a SAPLING 



NONSTOCKED 



1,000 



2,000 



3,000 

 THOUSAND ACRES 



4,000 



5,000 



Figure 20. — Commercial forest area by stand-size class and forest type group, 7948—50. 

 Tennessee's Timber Economy 



19 



