the demand for this type of material for other uses. 
More flexible methods of logging, however, such 
as those employing tractors and trucks, is now 
making it possible to reach with partial-cutting 
methods tracts too inaccessible for the conven- 
tional clear-cutting methods; thus a larger volume 
of potential veneer logs is now brought into the 
radius of availability. Future expansion, predi- 
cated upon a plentiful supply of raw material, will 
probably be restricted to western Oregon. 
ies 
g 
400 ie 154 
350 —-— 135 
8 
g 
fe) 
MILLIONS OF SQUARE FEET (3/8-INCH~ 3-PLY BAS/S) 
n 
o 
3° 
=) 
ue 
APPROXIMATE EQUIVALENT IN M/LLIONS OF BOARD FEET, LOG SCALE 
150 — — 58 
1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 
Ficure 31.—Plywood production of the Douglas-fir region 
Wood Preserving 
The 
speaking, a wood-using industry—is of considerable 
wood-preserving industry—not, _ strictly 
importance. ‘The prolongation of the life of wood 
products through treatment with preservatives is 
an important factor in holding the markets for 
wood products against the competition of substi- 
tutes and in reducing the depletion of the forests of 
this region. Fifteen plants were in operation in 
1935. The principal products treated that year 
were: 
96 
F 347405 
FicurRE 32.—Douglas-fir veneer log on lathe. The volume of 
Douglas-fir veneer produced in the region increased more than 250 
percent during the decade 1927-36 
Poles: (pieces) meee eee eee eee 71, 903 
Pilesi(linearsfeet) bese eee ee eee 452, 441 
Grossstiesi (pieces) Maecenas 2, 573, 875 
Crosstarms} (pieces) yen ae eee eee 40, 732 
Switch ties, timbers and lumber (board feet)... 50, 000, 000 
Secondary Wood-Using Industries _ 
The secondary wood-using industries have in- 
creased greatly in the last two decades, although, 
in comparison with the primary wood-using indus- 
tries, they are still far from completely developed. 
Their leading products are sash and doors, mill- 
work, boxes and crates, cross arms, furniture, wood 
pipes, tanks and silos, handles, caskets, wooden- 
ware, and vehicles. The principal woods used in 
these industries are Douglas-fir, western hemlock, 
Sitka spruce, western redcedar, red alder, and 
bigleaf maple. 
