Stand-Size Classes 



Sawtimber stands. — Stands with sawtimber trees 

 having a minimum net volume per acre of 1,500 

 board-feet, International )^-inch rule. 



Large sawtimber stands. — Sawtimber stands hav- 

 ing more than 50 percent of the board-foot \-olume 

 in large sawtimber trees. 



Small sawtimber stands. — Sawtimber stands ha\"- 



ing 50 percent or more of the net board-foot 



volume in small sawtimber trees. 



PoLETiMBER sT.^NDS. — Stands failing to meet the 



sawtimber stand specifications, but at least 10 percent 



stocked with poletimber and larger trees (5.0 inches 



d. b. h. and larger) and with at least half the minimum 



stocking in poletimber trees. 



Seedling and sapling stands. — Stands not quali- 

 fying as either sawtimber or poletimber stands, but 

 at least 10 percent stocked with trees of commercial 

 species and with at least half the ininimum stocking 

 in seedling and sapling trees. 



Nonstocked and other areas not elsewhere 

 CLASSIFIED. — Forest land not qualifying as sawtim- 

 ber, poletimber, or seedling and sapling stands. 



Diameter Measurement and Classes 



Diameter .^t breast height (d. b. h.). — Tree 

 diameter, outside bark, measured at 4.5 feet above 

 average ground level. 



Diameter class. — Trees were recorded in 2-inch 

 diameter classes, each class including 1.0 inch below 

 and 0.9 inch above the midpoint of the class; e. g., 

 the 8-inch class included all trees ranging from 7.0 to 

 8.9 inches d. b. h. 



Diameter inside bark. (d. i. b.). — Tree diameter 

 inside bark at any point specified. 



Hardwood Log Grades ^ 



Grade 1. — Butt logs at least 14.0 inches (upper logs 

 at least 16.0 inches) in diameter inside bark at the 

 small end. Minimum length of butt logs is 10 feet, 

 8 feet for upper logs. Five-sixths of the surface on 

 the three best faces must be clear of defect. Two clear 

 cuttings are allowed on any face, but the minimum 

 length of cuttings is 7 feet for butt logs and 5 feet for 

 upper logs. Cull deductions including sweep cannot 



' The hardwood log grades used are essentially those pur- 

 lishcd as "Interim Sawlog Grades for Southern Hardwoods," 

 by C. R. Lockard and R. D. Carpenter, Southern Forest 

 Experiment Station, 1947 {4). Persons interested in detailed 

 specifications should consult this publication. 



exceed 25 percent for butt logs and 40 percent for 

 upper logs. Such logs will normally yield about 65 

 percent No. 1 Common and better lumber. 



Grade 2. — Logs at least 12 inches in diameter 

 inside bark at the small end. Minimum length is 

 8 feet. Two-thirds of the surface on the three best 

 faces must be clear of defect. Three clear cuttings 

 are allowed on any face, but the minimum length of 

 cuttings is 3 feet. Cull deductions including sweep 

 cannot exceed 50 percent. Such logs for most species 

 will normally yield about 40 percent No. 1 Cominon 

 and better luinber. 



Grade 3. — Logs at least 8 inches in diameter inside 

 bark at the small end. Minimum length is 8 feet. 

 Minimum standards require that these logs be at least 

 50 percent sound and qualify at least for manufacture 

 of local-use lumber or railroad ties and timbers. Such 

 logs for most species will normally yield about 20 

 percent No. 1 Cominon and better lumber. 



Growth 



Net annual growth of sawtimber. — The change 

 during a specified year in net board-foot volume of live 

 sawtimber on commercial forest land resulting from 

 natural causes. 



Net .annual growth of growing stock. — The 

 change during a specified year in net cubic-foot vol- 

 ume of growing stock on commercial forest land 

 resulting from natural causes. 



Ingrowth. — The total \olume of all trees that dur- 

 ing the year reach the minimum diameter (5.0 inches) 

 for growing stock or the minimum diameter for 

 sawtimber of 9.0 inches for softwoods and 11.0 

 for hardwoods. 



Mortality 



Annual timber mort.ality. — The net volume re- 

 moved from live sawtimber or growing stock on com- 

 mercial forest land during a specified year through 

 death from natural causes. 



Timber Cut 



Timber cut from ltve s.a\\'timber. — The board-foot 

 volume of live sawtimber trees removed from com- 

 mercial forest land during a specified year as timber 

 products and logging waste. 



Timber cut from growing stock. — -The cubic-foot 

 volume of live sawtimber and poletimber trees re- 

 moved from commercial forest land during a specified 

 year as timber products and logging waste. 



34 



Forest Resource Report No. 10, U. S. Department of Agriculture 



