FOREST 



RESOURCES 



O F 



SOUTHEASTERN 



TEXAS 



Volume Estimates 



-S£>- 



<&r 



THE volumes of sound wood in the unit are 

 estimated in three forms: saw-timber volume, 

 cordwood volume, and these two combined in 

 a cubic-foot volume. The saw-timber estimate 

 includes all the material that has the size and 

 quality to make lumber, while the cordwood 

 estimate includes material not considered usable 

 for saw-timber but which is convertible into such 

 low-grade commodities as pulpwood, fuel wood, 

 and fence posts. These two volumes do not over- 

 lap and when added together represent the total 

 resource. The table giving the volume in cubic 

 feet inside bark shows the sum of the volumes of 

 the two previous classes of material, expressed in a 

 measure common to both. 



Saw-timber Volume 



To be included in the saw-timber volume 

 estimate, pine and cypress trees must have a diam- 

 eter at breast height of at least 9 inches outside 

 bark, and hardwoods must be at least 1 3 inches in 

 diameter. In addition, merchantable trees must 

 contain either one sound butt log 12 feet or more 

 in length, or 50 percent of their gross volume in 

 sound material. The estimates are based on 

 current utilization practice as to stump heights, 

 minimum top diameters, and woods cull. Volume 

 was included to the upper limit of usable material 

 in the tops rather than to a fixed top diameter, but 

 no pine logs less than 5.5 inches in diameter at the 

 small end or any hardwood logs less than 8.5 

 inches in diameter at the small end were included. 

 The top diameter of pines actually averaged 9.9 

 inches. 



The total net saw-timber volume as of January 

 1, 1935, expressed in the Doyle rule, is 12% billion 

 board feet. Table 6 presents this volume by 



species, and also the International-rule (%-inch 

 kerf) volume of nearly 19% billion board feet, 

 which closely approximates green lumber tally, 

 and the Scribner-rule volume of about 17 billion 

 feet. About 90 percent of the total net saw- 

 timber volume occurs in stands of more than 2,000 

 board feet per acre. Stands of this density 

 occur on 50 percent of the forest area. 



Table 6. — Net volume in Doyle, Scribner, and International 

 Y^-inch rules classified according to species group 



Species group ' 



Doyle 



Scribner 



International 



Pines: 



M board feet 



726. 600 



1, 883, 600 



4, 482, 300 



M board feet 

 1, 020, 000 

 3, 003, 300 

 6, 513, 400 



M board feet 

 1, 175, 600 



Shortleaf _ _ - - 



3, 601, 200 



Loblolly . - 



7, 633, 000 



Total 



7, 092, 500 



10, 536, 700 



12,409,800 



Hardwoods: 



Red gum 



1,011,200 



558, 600 



1. 424, 200 



1, 070, 100 



117, 800 



977, 000 



1. 231, 800 

 685, 600 



1. 728, 200 



1, 290, 000 

 153, 400 



1, 253, 900 



1, 353, 700 



Black gum 



787, 700 

 1, 891, 400 



White oaks 



1. 409, 100 



Ash 



Other hardwoods.. ._ . 



167, 500 

 1, 381, 700 



Total 



5, 158, 900 



6, 342, 900 



6, 991, 100 





12,251,400 



16, 879, 600 



19,400 900 







' Volumes of scrub oaks and special-use species are not included. 



Table 7 distributes the board-foot volume by 

 the Doyle rule into species groups and forest con- 

 ditions. The pine species account for about 58 

 percent of the total board-foot volume and amount 

 to over 7 billion board feet. About 4% billion 

 feet of this is loblolly pine, the largest share of any 

 single species in the unit. The pine volume, ex- 

 pressed in percent of the total volume, is divided 

 into longleaf, 6 percent; shortleaf, 15 percent; 

 and loblolly, 37 percent. 



t6 



