IRRIGATION FARMING. 



next June, when a. ring of alfalfa dies on the margin of 

 the circle. Its annual spreading indicates a fungous 

 trouble. The disease spreads slowly, about fifty feet 

 each year, and its advance is not stopped by plowing 

 around the diseased spots. Hence the fungus mu>t 

 attack the healthy plants for some time before there are 

 any visible signs of disease. The disease attacks the 

 crown and upper portion of the root, no fungus being 

 found below sixteen inches from the surface. The fun- 

 gus is identical with the cotton-root rot. Salt, kerosene, 

 and other remedies have been found to be partially ef- 

 fective, but no sure cure or preventive has yet been 

 found. 



In other humid climates some farmers have found 

 that the plant is affected with leaf spot. This disease is 

 found in nearly every place where alfalfa is grown, in the 

 moist Atlantic States. Usually it does not attack the 

 plant until the second year's growth, when the plant is 

 able to survive the disease. Sometimes, however, it 

 completely destroys seedling plants. The disease shows 

 itself as minute dark-brown spots of irregular shape 

 upon the green or discolored leaflet. The center of each 

 spot forms a pustule. In this are developed the spores, 

 which are set free by the breaking of the epidermis. 

 The disease readily survives the winter, and may develop 

 year after year in the same field. In serious ca>es cov- 

 ering with straw and burning will stop the disease. It 

 may be held in check by frequent cuttings. 



Dodder is an enemy that has given alfalfa more or 

 less trouble "out West." It is a small annual parasitic 

 plant with yellow or reddish-yellow twining stems, which 

 wind themselves around the stems of alfalfa, clover. "i % 

 similar plants near the ground, taking its nourishment 

 from its host. It has small, colorless, scale-like leaves, 

 and produces clusters of ten or more flown-s. each of 

 which contains four small grayish seeds which are about 



