yi DEPARTMENT BULLETIN 1425, U. S. DEPT. OF AGRICULTURE 
TABLE 1.—Average annual production of western sofiwood lumber by regions * 
[In millions of board feet] 


Douglas aioe Califor- tape S 
Kind of wood fir ping nia pine | “Vooq | Total 
region region region region 
Incense cedar ((Libocedrus decurrens) --=---- 222 ee oes eee ee S24. s eee 32 
Western red cedar (Thuja plicata)--------------------- 218 Ba" | ioe le en 251 
Douglas fir (Pseudotsuga taxifolia) - -..-.-------------- 6, 539 292 103 104 7, 038 
\Willlnie Wine. eee ee eee se se seceeissseos 17 73 183 16 289 
Western hemlock (Tsuga heterophylla)?__.__---------- 819 Qi Soa eee il 829 
Western larch (Larix occidentalis) ._..------------------ 1 212) 22S se es | See 273 
Lodgepole pine (Pinus contorta)___-..-----------------|--------.- GSE pie ate eee |) eT aes 5 
Sugar pine (Pinus lambertiama)*___~-_.---------------- S fwieyee went 14ik a eee 229 
Western white pine (Pinus monticola)§__-..-_.-------- 1 BL OR pe Mecca Men senha er 394 
Western yellow pine (Pinus ponderosa)®___-_-_.------- 16 1, 023 846 2 ee seen 1, 885 
Redwood (Sequoia sempervirens) ----------------------|-------- go|[exees222)a/sebse054 536 536 
Sitka spruce (Picea sitchensis) _-_---------------------- BE fl ie eset WR BE 5 2 339 
Engelman spruce (P. engelmannii) ---~----------------|---------- DON ao een | eee 25 
MPotaly Ae PHOT aU a PA YON Th Se ee 7, 956 2, 125 1, 378 659 | 12,118 

1 Figures (rounded) based on five-year production records; Douglas fir region includes western Oregon 
and Washington; Inland Empire pine region includes Montana, Idaho, eastern Oregon and eastern _Wash- 
ington; California pine region includes California, Nevada, and Clamath Falls district of Oregon; Califor- 
nia redwood region includes redwood belt in California. ; 
2 Includes the following species: White fir (Abies concolor), lowland white fir (A. grandis), silver fir (A. 
amabilis), red fir (A. magnifica), alpine fir (A. lasiocarpa), and noble fir (A. nobilis). 
3 West Coast hemlock. 
4 California sugar pine. 
5 Idaho white pine. : : ; 
6 Pondosa pine, California white pine. 
The air seasoning of lumber is, however a complex problem if 
anything like real efficiency is to be obtained. In working out the 
proper solution five distinct objectives must be kept constantly in 
mind: 
1. Minimum depreciation of stock. 
2. Rapid rate of drying. 
3. Low, uniform final moisture content.? 
4, Economy in operating cost. 
5. Reasonable yard space. 
Other complications of the problem must also be recognized. The 
various species, grades, and sizes of stock require individual con- 
sideration. Owing to climatic and other differences, the answer for 
one yard will not always hold for another. The effects of seasonal 
weather variation must also be provided against by each yard sepa- 
rately. 
Reon attainment of any one of the five principal objectives 
may often preclude the full realization of the others. Since actual 
efficiency in air seasoning must in the final analysis be measured by 
the profit-and-loss yardstick, it is necessary that these five objectives 
be adequately balanced to the best advantage of the producer. 
2The fact that wood shrinks and swells with changes in moisture content makes it 
highly desirable that seasoning result in a final moisture content suitable for the condi- 
tions of final use, but absolute attainment in this direction is hardly possible on account 
of the varied purposes for which wood is employed and the wide range of atmospheric 
conditions under which it is used. This can be illustrated in a concrete way. Wood 
thoroughly air-dried has a moisture content at Galveston, Tex., of about 17.5 per cent 
and at Phoenix, Ariz., of 7.5 per cent. In the general Middle West territory wood, to 
give the most satisfactory results, should have a moisture content of 6 to 8 per cent for 
interior work and 12 to 15 per cent for outside use. These differences indicate forcibly 
that the final moisture-content problem is a difficult one, but they also emphasize its 
importance to the operator. 
