36 DEPARTMENT BULLETIN 1425, U. S. DEPT, OF AGRICULTURE 
To determine the relative efficiency of different spacings with 
even-width stock, tests were conducted on both select and common 
grades of pine during different seasons of the year and at several 
plants in the inland empire. The results obtained (Table 5) were 
very consistent and point conclusively to a definite relationship 
between drying conditions and width of spacing. They show that 
the rate of drying is materially affected. Stain losses can be greatly 
reduced by increasing the spacing, and increases of the interval up 
to 4 inches at least do not appreciably increase the occurrence of 
DESCRIUIGN, Of5 FYLE SS 
STOOGKAS AE AVE NE COPUUN HESTERN HEUTE PIME 
BOK TIPE PILES 
V6 FEET SQOUARL VIO COURELS 
VX CROSGSLRE : 
CAT. SLANG BETHEL BOACDE-2,3 AND 2° 
8 
40 
Moisture content, per cent 
20 
10 

° 
LF LOM 27 (ES 10 IF 24)\t 8 eG Ae FES LAS TON FS NE 100 (U7 Zea Ne 
DEC. JAN. 
AUG. SEPT. OCT. NOV. 
Fic. 5.—Comparative ‘ pile average”’’ drying rates for stock piled with different 
spacing between boards 
shrinkage defects. Figures 5 and 6 allow a visualization of the 
influence which the spacing exerts upon drying rates. Figure 6 also 
indicates that by this means the lag in drying in the lower part of 
the pile can be to some extent reduced. 
TABLE 5.—Effect of different spacing between boards in the lumber pile 



f Degrade Loss per M feet Final | Time re- 
Gia cinigy i See COS: fist Lhe evn doves lL poh edi Ulaleenks eal is see eR OTS hl AGERE 
stained ture for air- 
Stain | Check | Knots} Total | Stain Check | Total |content} drying 




Inches |Percent| Per cent| Per cent| Per cent| Per cent Percent| Weeks 
4 FL Sard 0. 4 1.8 5.9 $0. 57 $0.07 | 1$1. 25 15. 5 15 
3 29. 4 6. 4 2 255 9. 2 1. 33 .16 12 BB" 15.0 18 

2 38. 4 10.5 5 UI 2. 4 13. 6 1. 75 14 1 2. 87 15.7 25 
1 Total figures are not the sum of those in the 2 preceding columns. 
‘The practice of spacing even-width western softwood lumber for 
air seasoning is naturally far from uniform. The numerous species, 
grades, and sizes involved, the great variation in general piling prac- 

