98 Diseases of Truck Crops 



Seed beds are very often attacked by mole crickets. 

 They may be kept out by a wire gauze floor. When 

 the seed bed is made and the earth is dug out to a 

 depth of one foot or more, a sheet of galvanized or 

 copper mosquito netting is placed at the bottom, com- 

 ing up at the sides, and projecting a couple of inches 

 above ground. Ants, too, are often destructive to 

 seed beds. They feed on the seed and carry it away 

 to their nests. This is especially true with lettuce 

 seed. Ants are best controlled by pouring half a 

 pint of carbon bisulphide in each nest and immedi- 

 ately plugging its entrance. 



Other Seed Treatment. Since seed may be a 

 carrier of diseases, it is essential that we have a 

 method of treatment capable of destroying the dis- 

 ease-producing organism in its initial stage. Ex- 

 posing the seed in hot water at various degrees of 

 temperature is effective in controlling certain smuts of 

 grains. Treating the seed with sulphuric acid accel- 

 erates the germination of certain hard seed, destroy- 

 ing at the same time spores of fungi which may adhere 

 to the exterior of the epidermis. Unfortunately 

 there have been no extensive trials made of the effect 

 of hot water and sulphuric acid, in accelerating the 

 germination, and preventing the diseases which are 

 carried on or within the seed of truck crops. How- 

 ever, the treatment of seed (especially tubers) with 

 corrosive sublimate or formaldehyde is now exten- 

 sively practiced. Where the soil in the bed is ster- 

 ilized, seed treatment becomes necessary. With the 

 exception of tubers or roots, seeds should preferably 



