WEEDS OF GRAIN AND FORAGE CROPS 53 



a parasite, it has none of the green coloring matter of 

 most plants, for it is not able to manufactvure starch and 

 other organic material from the inorganic substances in 

 earth and air. Instead of this, it utilizes for its growth the 

 materials thus organized by the green leaves of its host. 

 The Dodders are commonly yellow or orange in color. 

 They have no leaves. 



The seeds of Dodder are a common impurity in many 

 grain, grass, and forage seeds. Such seeds should, of 

 course, be carefully inspected before planting, and if seri- 

 ously infected should not be used. When a field is al- 

 ready infested, the Dodder may be destroyed by mowing 

 and removing the crop before the Dodder blossoms, or 

 later the crop, may be mowed and the ground burned over 

 after the crop thus cut has dried sufficiently to burn. In 

 Western alfalfa fields Dodder is often troublesome the 

 first year after seeding, though less so in later years. 



Preventive Measures 



Any study of the weeds that infest grain and forage 

 crops makes it obvious that the most important methods 

 of preventing injury by such pests are: first, the sowing 

 of clean seed, that is, grain free from the seeds of weedy 

 plants ; second, the use of fertilizers free from weed seeds ; 

 and third, a proper rotation with other crops. To insure 

 pure seed, constant inspection by state and government 

 officials of all seeds offered for sale is necessary. To in- 

 sure fertilizers free from weed seeds, care in feeding do- 

 mestic animals is necessary. To insure proper rotation of 

 crops, the adoption of improved agricultural methods in 

 every community is necessary. With these conditions 

 right there need be little trouble from weedy plants in any 

 locality. There is always danger, however, that some new 



