58 DEPARTMENT BULLETIN 1425, U. S. DEPT, OF AGRICULTURE 
markets by water, and the bulk of these water-borne shipments, as 
well as of the considerable rail shipments, is made up of green lum- 
ber. The region, moreover, is an unusually large producer of thick 
stock. or sizes thicker than 1 inch. Probably 380 per cent of the 
regional cut consists of dimension (2 inches thick), and an additional 
20 per cent of planks, small and large structural timbers, squares, 
railroad ties, and the like. Less than 20 per cent goes into common 
boards. 
Only an approximation of the quantity of lumber air seasoned in 
the Douglas fir region can be given. Practically all the manufactur- 
ing plants are equipped with dry kilns, with the exception of a few 
cargo mills, the tie-cutting plants, and the small portable and custom 
mills. Hence it is that practically all the clear lumber and a small 
proportion of the dimension and common boards, amounting to about 
35 per cent of the total lumber cut, is dried in kilns. Fully 50 per 
cent of the cut is shipped green, since for the large proportion 
shipped by water there is no incentive to reduce the weight of the 
lumber through seasoning. Only about 15 per cent of the regional 
output is alr seasoned or partially air seasoned, and this consists 
chiefly of dimension and common boards. 
In the air-seasoning practice of the region the width of the pile 
alleys is generally good, but spacing at the rear and at the sides of 
the pile is usually inadequate. Foundations, especially in the older 
yards, are entirely too low. Although the box and modified-box 
types of pile are commonly used, the random-length type is em- 
ployed to a large extent, particularly in piling No. 2 and No. 3 
common boards and dimension, shiplap, and box grade lumber. 
Square, low piles are most frequently found. Practically all stock 
is self-crossed. The spacing between boards in a course will average 
only about 21% inches and chimneys are little used. 
RESULTS FROM PRESENT PRACTICE 
Accurate records of air-seasoning depreciation in Douglas fir 
common as summarized in Tables 7, 8, and 9, show definitely that 
season check and loose knots are the principal causes of degrades. 
Season check, which is heaviest during the summer months, is due 
principally to the practice of self-crossing, which results not only in 
a heavy loss in the stock crossers, but also in an increased loss in the 
piled stock because of the crossers. “ Fall-down” from loose knots 
is greater in machining than in seasoning, and there is little oppor- 
tunity to reduce this defect in seasoning since it is in large measure 
due to structural causes. However, all direct seasoning losses for 
the region are subject to reduction by reasonable additions to the 
piling cost. 

