Causes of Diseases in Crops 73 



way soil diseases be spread. Wind storms cannot 

 well be prevented. Perhaps the best safeguard is 

 never to allow bare spaces in the field, and to have 

 the soil thoroughly covered with vegetation. In 

 windy localities, crops should be planted closer than 

 is generally the custom. 



RAINSTORMS 



Heavy rains when pounding on tender plants may 

 cause considerable damage in tearing tender foliage. 

 Another indirect injury is the pounding and packing 

 of the soil. This shuts out the free circulation of air 

 and is bound to interfere with the normal metab- 

 olism of the plant. Heavy rains by pounding on the 

 soil, splash mud and sand on all parts of the plant. 

 This encourages infection of numerous diseases, and 

 reduces the shipping and market value of the crop. 



Besides rainstorms, frequent showers are detri- 

 mental to truck crops cultivated for their fruit or 

 seed. They prevent pollination by insects. There 

 is, of coiorse, no feasible method of preventing vm- 

 favorable weather conditions. Deep plowing may 

 encourage the absorption of all the rain and prevent 

 baking. "Windbreaks too may protect crops from 

 severe storms. 



HAILSTORMS 



The injury to truck crops from this source is con- 

 siderable. It results in deep bruises or cuts in stem. 



