10 
BULLETIN 510, U. S. DEPARTMENT OF AGRICULTURE. 
durable grades at times becomes a considerable problem, not alone at 
the mills but also in the retail yards. In fact, the writer has been 
told by certain retailers that deterioration due to decay in these low 
grades had become so serious with them that they had discontinued 
carrying such hazardous stock. 
In the case of hemlock, spruces, firs, low grades of pine, and cer- 
tain of the less durable hardwoods, storage difficulties are bound to 
develop at times during exceptionally wet seasons, but much of the 
trouble can be fore- 
stalled by applying 
the proper methods 
of sanitation. 
It is necessary that 
if such material is to 
enter into the con- 
struction of buildings 
it should be entirely 
free from fungous 
infection. Responsi- 
bility for clean lum- 
ber must rest with 
the lumberman. 
CONDITION OF 
STORAGE SHEDS 
AT MILLS. 
Fig. 5. — Pine lumber piled in a swamp on high skids over 
standing water at New Orleans, La. Note the luxuriant 
vegetation, which checks proper air circulation beneath 
the piles. 
P67F As noted before, 
many mills, includ- 
ing some of the larger 
ones, are operating 
far as decav is con- 
under serious disadvantages of location as 
cerned. The better types of storage sheds are inclosed at the sides, 
with ample ventilation beneath (fig. 6), but those open on both 
sides are not uncommonly met with. The exclusion of water from 
stored lumber becomes a necessity when such material is put in close 
piles under cover, where the drying action of wind and sun does not 
have full play. This is particularly true where sheds are built over 
low swampy ground where the vapors on rising from the wet soil are 
more or less imprisoned, keeping the air at a high humidity. A little 
extra moisture in such cases may be sufficient to permit the outbreak 
and rapid spread of fungous infections. 
The greatest source of danger in storage sheds lies in placing the 
lumber too close to the ground, and several instances have been noted 
