26 
BULLETIN 510, U. S. DEPARTMENT OE AGRICULTURE. 
Besides the proper sticking and lateral spacing of lumber, a cen- 
tral flue one board wide running vertically through the middle of 
the pile is often of decided advantage. Many millmen recognize 
this as good practice, but few of them consider they have sufficient 
yard space to carry 
out the method con- 
sistently. 
Another factor 
which enters into the 
storage of lumber is 
the piling of stock in 
even or approximately 
uniform lengths (see 
fig. 26). A few mills 
consider that such pre- 
liminary sorting is 
feasible from • an eco- 
nomic standpoint, on 
account of the greater 
facility with which 
such stock can be 
billed out. From a 
pathological stand- 
point the practice is 
highly commendable. 
Uneven lengths allow 
rains to beat in, and also offer convenient and favorable lodging 
places for fungous spores. Likewise, marked disparities in length 
permit considerable warping of the ends, which often project out 
several feet from the main body of the pile. Figure 29 shows this 
condition in an exag- 
gerated form. To 
protect the ends of 
the lumber from 
beating rains as far 
as possible, the cross 
strips should be 
placed at least flush 
with the ends, both in 
front and behind. 
There still remains 
the question of roof- 
ing the piles. The commonly accepted pitch for lumber piles is 1 
inch to the foot, and with a loose roof of lapped boards the greater 
part of the rainfall will drain away. The roofs must necessarily 
extend somewhat beyond the piles, in order to carry the drip clear of 
Fig. 26. — Lumber piled in even lengths in a southern 
mill yard. The crossing strips consist of the narrower 
widths of lumber. 
Fig. 27. — Edge-piled 2 by 4 pine at an Arkansas mill. This 
method of piling permits better vertical air circulation 
and consequently more rapid drying and less danger 
from decay during storage. 
