TREATMENT FOR SPECIAL WEEDS 113 



in keeping this weed down. One writer states that by 

 keeping it in pasture four or five years the weed is killed. 

 Mr. Cox, in addition to cultural methods, recommends the use 

 of alfalfa as a weed exterminator. The plowing should be thor- 

 ough and done as soon as the grain is removed in July or Au- 

 gust, but it need not be deep, as the roots extend several feet 

 into the soil and cannot be reached by plowing. Where 



Fig. 34A. Wild morning glory, or bindweed (Convolvulus septum). 

 (Photograph, Charlotte M. King.) 



the weed is common the plowing should be followed by 

 disking and harrowing arid the roots should be exposed 

 to the sun. One correspondent recommends corn, oats, 

 and pasture. Another recommends millet, sorghum, and 

 buckwheat as effective in the destruction of the weed. 

 \Yhen a cornfield contains a considerable amount of the 

 irorning glory the cultivation must be frequent and the 

 hoe should follow the cultivation, especially to destroy 

 the plants which make their appearance around the hills. 



