156 Weeds. 



wise destroyed. This is particularly neces- 

 sary with wild mustard and similar weeds, 

 which have the power of maturing their 

 seeds even after the plants are removed 

 from the ground. 



8. Spraying. A method which has been 

 quite commonly practiced in some sections 

 in recent years, and is now considered by 

 many to be one of the best means of com- 

 bating mustard and other broad-leaved 

 weeds in grain fields, meadows and pas- 

 tures, is spraying with a solution of salt, 

 iron sulfate, or some other chemical. 

 Spraying experiments to kill weeds were 

 first begun in this country about 1896, but 

 it is only in recent years that the practice 

 has become at all general. This method, 

 even as it is at present developed, can not 

 take the place of the more generally rec- 

 ognized methods of fighting weeds, such as 

 the sowing of clean seed, thorough culti- 

 vation, and crop rotation. It is effective, 

 however, in checking the growth of weeds 

 in those sections where no definite crop 

 rotation which includes the growing of cul- 

 tivated crops is practiced, but where crop 

 after crop of small grain is grown on the 

 land. 



