spp.), elm (Ulmus spp.), hickory (Carya spp., syn., Hicoria 

 spp.), holly {Ilex opaca), persimmon (Diospyros virginiana) 2 and 

 associated minor species. 



Tree Classes 



Sound tree. — A sawlog-size tree that is, or an under-saw- 

 log-size tree that gives promise of becoming, a saw-timber 

 tree. 



Sawlog-size tree. — A tree with the following minimum 

 diameter outside of bark: Hardwood, 13.0 inches at 4)4 

 feet above the ground; cypress, 9.0 inches at 2% feet above 

 the butt swell; all pine (except turpentined longleaf and 

 slash pines) 9.0 inches at 4J4 feet above the ground: tur- 

 pentined longleaf and slash pine, 9.0 inches at 10 feet 

 above the ground. 



Saw-timber tree. — A sawlog-size tree that contains one 

 sound butt log at least 12 feet long, or that has at least 

 50 percent of its gross volume in sound material. 



Cull tree. — A sawlog-size tree less than 50-percent sound 



2 Since holly and persimmon are used primarily for 

 special purposes, such as bobbins, shuttles, and parts of 

 sporting goods, they were not included in the saw-timber 

 estimate. 



or so limby, crooked, or otherwise defective as to prohibit 

 its use for saw timber. An under-sawlog-size tree that 

 will not become a saw-timber tree because of limbs, crook, 

 etc., or that is sufficiently unsound to indicate the likelihood 

 of its future loss from the stand. 



Diameter Classes 



Two-inch diameter class. — The 10-inch diameter class in- 

 cludes trees from 9.0 to 10.9 inches d. b. h., the 12-inch 

 class, trees from 11.0 to 12.9 inches, etc. 



Log Rules 



Doyle log rule. — The formula for a 16-foot log was used: 

 V={D— 4)2. 



Scribner log rule. — The formula for a 16-foot log, with 

 allowance for a %-inch saw kerf, was used: V=0.79D 2 - 



— 2D — 4. This formula was derived by Donald Bruce and 

 Francis X. Schumacher from the values of the original 

 Scribner log rule. 



International log rule. — The formula for a 16-foot log, with 

 allowances for }£-inch taper in 4 feet and for a J4-inch 

 saw kerf and ^6-mch shrinkage, was used: V=0.796D 2 - 



— 1.375Z)— 1.23. 



224951°— 41- 



