366 FIELD CROP PRODUCTION 



389. Harvesting. Because the potato is likely to be 

 injured by frost the crop should be dug and stored before 

 heavy freezes. ' Ordinarily late potatoes are dry when the 

 vines die down, indicating maturity of the tubers. How- 

 ever, when the vines have died down as a result of late 

 blight, it is well to wait some ten days before digging, as 

 the chances of rot in storage are thereby greatly lessened. 

 Potatoes should be dug when dry and placed in storage at 

 once. In a small way potatoes are dug with a fork or 

 potato hook, but on a larger scale the potato digger drawn 

 by horse power is commonly used. The potato box or 

 crate is largely used at present to replace the rougher 

 handling in bulk by pouring from baskets into the wagon 

 bed and shoveling into the cellar or storage. 



390. Storage. Potatoes freeze easily and the tem- 

 perature in storage should never reach the freezing point. 

 While 34 F. is recommended as a safe storage temperature 

 the tubers will have a better cooking quality if stored at a 

 temperature somewhat higher, ranging from 35 to 40 F. 



Ordinary cellars are usually utilized for storage. Where 

 this is done, it is well to construct a flue for conducting air 

 into the cellar from the outside at the level of the cellar 

 floor and have an opening at the top of the cellar to allow 

 the warm air, laden with gases and impurities, to pass off. 

 The cellar should be kept dark and some means of arti- 

 ficial heat should be provided in case there is danger of 

 freezing. The loss in storage from fall till April or May 

 will vary from 5 to 12 per cent, 10 or 12 per cent being 

 common. This loss is due to loss of moisture and respira- 

 tion. If the potatoes are diseased, the loss will be in excess 

 of this figure. 



391. Insects. The Colorado beetle (Leptinotarsa decem- 

 lineata) which is the familiar striped "potato bug," is the 



