44 Diseases of Greenhouse Crops 



ment. With lettuce seed, for instance, there is a 

 higher per cent, of germination usually obtained in 

 the sterilized soil. With tomatoes, however, ger- 

 mination is retarded under similar soil treatment. 

 On the average, germination is favored by soil ster- 

 ilization. This is well shown in Table 2.* 



Effect of Soil Sterilization on Plants. That soil 

 sterilization is practicable cannot be doubted. With 

 some crops, the beneficial effect is especially marked. 

 The Massachusetts Experiment Station t found a 

 considerable increase in the production of violet 

 blossoms as a result of soil sterilization. This is 

 well shown in Table 3. 



•From the Massachusetts Agr. Expt. Sta., 15th Rept.: 40-42, 1903. 

 t Massachusetts Agr. Expt. Sta., lath Ann. Rept.: 165-167, 1900. 



