See 
4 - BULLETIN 729, U.S. DEPARTMENT OF AGRICULTURE. 
A uniform temperature of 31° to 32° F. and a relative humidity of 
from 85 to 90 per cent are accepted as standard for the storage of — 
_apples. The usual humidity of refrigerated storage rooms is about 85 
per cent. 
Apples in cold storage should be inspected frequently in order that 
they may be removed and sold while they are still in good condition. 
POTATOES. 
Potatoes for storage should be “practically free from frost injury 
and decay and free from serious damage caused by dirt or other foreign 
matter, sunburn, second-growth, cuts, scab, blight, dry rot and other 
diseases, insects or mechanical means” as described in Markets Docu- 
ment No. 7: Potato Grades Recommended by the United States De- 
partment of Agriculture and the United States Food Administration. 
In order to reduce the danger of deterioration from disease and from 
exposure to atmospheric changes, potatoes should be placed in storage — 
aS soon as practicable after being harvested. When stowed in bulk | 
in either common or cold storage, potatoes shculd be piled not deeper 
than six feet, and the bins or compartments should be constructed 
with slat sides and bottoms to provide ample ventilation. They should 
not be stowed on earth floors. Each bin should contain not to exceed 
60,000 pounds of potatoes. When stowed in crates or bags, the con- 
tainers should be so piled as to permit unobstructed circulation of 
air on all sides. 
The temperature of storage rooms should not be lower than 35° nor 
higher than 40°. In cellars or common storage houses the ventilators 
should be of ample size to permit of quick cooling in the autumn to 
a temperature of 40° or lower. The relative humidity of the storage © 
rooms should be from 80 to 90 per cent to prevent shriveling or soften- 
ing of the potatoes, but it should not be high enough to cause a deposit 
of moisture on the potatoes. Daylight should be entirely excluded 
from the storage room unless the potatoes are to be used for seed. 
In properly constructed and well managed common storages, pota- 
toes which are sound and mature when stored in the autumn should 
keep in a good merchantable condition from four to six months. Under 
less favorable conditions earlier deterioration may be expected which 
may require the removal and marketing of the product within three 
or four months. In sections where a sufficiently low temperature cannot 
be maintained, potatoes can be held in common storages for only short 
periods without danger of serious deterioration. When common storage 
is used, frequent inspection is necessary to avoid holding them beyond 
their prime market condition.*' In cold storage, potatoes may be held 

iStuart, William. Potato storage and storage houses. U. S. Department of 
Agriculture, Farmers’ Bulletin 847. 1917. 
