84 Experiments in Keeping Potatoes. 



The situation should t>3 naturally dry, and ample facilities 

 should be provided for running off the water. 



Shelter supplied by a hedge, wood, or building had 

 considerable influence on the frost. 



The potatoes should be as dry and clean as possible at the 

 time of storage. All diseased and damaged tubers should at 

 that time be removed. 



The clamps should not be too small. The temperature of 

 large clamps was always higher than that of small ones, so 

 that they suffered less from frost. The best results were got 

 in clamps having a breadth of 4 to 5 feet, and a height of about 

 3 feet. The length must be regulated by circumstances. 



Straw supplemented by soil was found to be the best 

 covering material. The straw should be strong, so as not 

 to collapse too much under the load of earth, and the straw 

 covering should not be less than 4 inches, and need not be 

 more than 6 inches in thickness. It should be thoroughly 

 dry, so that it may attract superfluous moisture from the 

 mass of the tubers. The covering of soil, 20 inches, recom- 

 mended for German conditions appears to be much beyond 

 English requirements. 



Potato haulm, as it often holds spores, is not suitable for 

 immediate contact with the potatoes. It may, however, be 

 used as supplementary covering, in which case the clamp 

 would consist of a layer of straw, then 3 or 4 inches of earthy 

 then 3 or 4 inches of haulm, and finally an equal thickness 

 of earth. 



Loose haulm, or rough fold manure, on the outside of the 

 clamp, is not recommended on account of its catching and 

 retaining rain. 



Good ventilation is essential. This may be secured by 

 leaving the ridge without soil, by placing pipes, wisps of 

 straw, etc., at intervals along the ridge, and in other ways. 

 The method of ventilation, however, that was found to give 

 the best results was arranged thus : — The potatoes in the 

 clamp were covered with about half their full allowance of 

 straw, and a spadeful of earth was thrown on here and 

 there to keep the straw in position. A scaffolding pole, 3 to 4 

 inches in diameter, was then laid along the ridge, and 



