STEAM STERILIZATION OF SEED BEDS FOR 

 TOBACCO AND OTHER CROPS. 



CONTENTS. 



Page. 



Importance of vigorous tobaccoseedlings 3 



Root-rot in the seed bed _ 4 



Old metho d of sterilizing tobacco seed beds . . 4 



The steam-pan method of sterilization 5 



Preparation of the seed bed for steaming . 6 



Effect of frost in the soil . 



Fall steaming of the seed bed 6 



Equipment needed for steaming seed beds. . . 7 

 Construction of the steaming pan 8 



Page. 



Carrying out the steaming process 10 



Temperatures secured 11 



Cost of steaming 12 



Important considerations 13 



The formaldehyde method of sterilizing seed 



beds 14 



Application of the steaming process to crops 



other than tobacco. . . 15 



IMPORTANCE OF VIGOROUS TOBACCO SEEDLINGS. 



IN TOBACCO PRODUCTION, to grow the right sort of seedling 

 plants is of special importance. Successful transplanting from 

 the seed bed to the field requires vigorous seedlings, and the growth 

 of the crop in. the field, especially in the early stages, is largely de- 

 pendent upon the character of seedling used. Great importance is 

 to be attached to securing strong, healthy seedlings. The young 

 plants in the bed are liable to be injured, and therefore it is necessary 

 to protect them from parasitic and other enemies, which may injure 

 and retard their growth or even kill them. Chief among these ene- 

 mies are weeds and certain fungous diseases, especially root-rot. 

 Spots in the beds are also frequently found where the soil conditions 

 are such that normal development can not be attained. 



These difficulties can be eliminated or greatly reduced by the 

 sterilization of the seed beds, which now is recognized as an import- 

 ant feature in tobacco growing. Seed beds are sterilized for the con- 

 trol of diseases and to kill weed seeds and hibernating insects. When 

 properly done, the saving in weeding costs usually pays for the whole 

 operation of sterilization. The process has the additional advantage 

 of insuring freedom from diseases and the production of more vigor- 

 ous seedlings. 



Sterilization by surface burning has been widely practiced for 

 generations in the South, and in fact has been used at one time or 

 another in nearly all tobacco districts. In the southern districts it 

 has been customary to select each year a new location for the seed 



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