30 THE OUTLOOK FOR TIMBER IN THE UNITED STATES 



Table 20. — Growing stock and sawtimber inventories on commercial timberlands, by species, 1970 



Species 



Growing stock 



Volume 



Proportion 



Sawtimber 



Volume 



Proportion 



Eastern softwoods : 



Southern pines 



Spruce and fir 



White and red pines 



Cypress 



Other » 



Total 



Eastern hardwoods : 



Select white and red oaks 



Other oaks 



Hickory 



Hard maple 



Ash, walnut, and black cherry 



Sweetgum 



Yellow-poplar 



Yellow birch 



Other 



Total 



Total eastern 



Western softwoods : 



Douglas-fir 



Western hemlock 



True firs 



Ponderosa and Jeffrey pines.. . 



Spruce 



Lodgepole pine 



White and sugar pines 



Redwood 



Other 



Total 



Western hardwoods 



Total western 



All species 



Million cu. ft. 



74, 622 



17, 322 



8,348 



5,034 



12, 193 



Percent 



11.5 



2.6 



1.3 



.8 



1.9 



Million bd. ft. 

 259, 059 

 23, 486 



26, 874 

 19, 111 



27, 407 



Percent 



10.7 



1.0 



1. 1 



.8 



1. 1 



117, 519 



18. 1 



355, 937 



14.7 



32, 613 

 38, 796 

 12, 582 



11, 732 



12, 185 

 10, 527 



8,566 



3,249 



67, 426 



5.0 

 6.0 

 2.0 

 1.8 

 1.9 

 1.6 

 1.3 



10. 



85, 835 

 99, 069 

 30, 915 

 25, 758 



25, 405 



26, 318 

 25, 094 



7,323 

 134, 065 



3.5 

 4. 1 

 1.3 

 1. 1 

 1. 1 

 1. 1 

 1.0 

 .3 

 5.5 



197, 676 



30.5 



459, 781 



19.0 



315, 194 



48. 6 



815, 718 



33. 7 



96, 861 

 47, 540 

 45, 326 

 38, 292 

 26, 296 

 25, 530 

 8, 337 

 4, 428 

 21, 745 



14. 9 

 7.3 

 7.0 

 5.9 

 4. 

 3.9 

 1.3 

 .7 

 3.4 



520, 640 



251,012 



218, 772 



189, 897 



132, 225 



65, 273 



44, 392 



23, 627 



103, 515 



21. 5 

 10. 4 

 9.0 

 7.8 

 5.5 

 2.7 

 1.8 

 1.0 

 4.3 



314, 355 

 19, 330 



48. 4 

 3. 



1, 549, 352 

 55, 696 



64.0 

 2. 3 



333, 685 



51. 4 



1, 605, 048 



66.3 



648, 879 



100.0 



2, 420, 767 



100.0 



1 Includes 128 million cubic feet and 540 million board feet of ponderosa pine in eastern South Dakota and Nebraska. 



classes of softwoods (fig. 14). Increases in stand 

 volumes were especially large in the 5- to 11-inch 

 diameters. 



PLANT RESIDUES 



Wood residues from primary processing at 

 sawmills and other wood processing plants provide 

 an important part of the fiber supply for the pulp 

 industry and a significant potential for further 

 expansion of wood-based industries. 



Trends in Utilization of Plant Byproducts 



In recent years the wood-using industries have 

 made much progress in utilization of the round- 

 wood delivered to sawmills, veneer mills, and other 

 primary wood processing plants. In 1970, an esti- 

 mated 2.8 billion cubic feet of slabs, sawdust, 



veneer cores, and other similar material resulting 

 from the manufacture of lumber and other wood 

 products was used for pulp, particleboard, fuel, 

 or other products (table 24). This represented 

 about 74 percent of all such material produced. 



Use of these plant byproducts by the pulp in- 

 dustry was of chief importance, almost 1.8 billion 

 cubic feet (about 22 million cords) being used for 

 pulp in 1970, including nearly 2 million cords of 

 chip exports to Japan. Use of such material for 

 pulping increased nearly 18-fold between 1952 and 

 1970 (fig. 15). 



Volumes of plant byproducts used for other 

 products such as particleboard, although small, 

 also have increased substantially. Use of sawdust, 

 slabs, etc. for industrial and domestic fuel, on the 

 other hand, has declined sharply. 



