4 BULLETIN 729, U. S. DEPARTMENT OP AGRICULTURE. 



A uniform temperature of 31° to 32° F. and a relative humidity of 

 from S5 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 should 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. 1 In cold storage, potatoes may be held 



iStuart, William. Potato storage and storage houses. U. S. Department of 

 Agriculture, Farmers' Bulletin 847. 1917. 



