1911.] PUBLIC DOCUMENT — No. 31. 31 



bacteria ar^ not ordiiiai-ily j)resoiit in soils whore alfalfa lias 

 not ])reviouslj been grown. A 2)ossible exception is afforded 

 by soils where sweet clover {Melilotus alba) is indigenons and 

 abundant. This plant, however, is comparatively rare in Mas- 

 sachusetts, and in almost all cases, therefore, it is advisable to 

 bring in the appropriate alfalfa bacteria by inoculation. Two 

 methods may be followed : — 



(1) Soil from a well-established alfalfa field where root nod- 

 ules are abundant may be worked into the soil where the seed is 

 to be sown. The quantity needed will range between about 300 

 and 400 pounds per acre. Care should be taken that soil which 

 is to be so nsed be not long exposed to the light nor allowed to 

 dry excessively. It should be spread, if possible, towards night 

 or on a cloudy day, and immediately harrowed in. 



(2) A culture may be used. A number of different artificial 

 cultures are now produced and rec<mimended for the inoculation 

 of the different legumes. The United States Department of 

 Agriculture sends out a material known as " Nitroculture." 

 This is in fluid form. An American agency of a European com- 

 pany produces and offers a jelly-like culture known as "" N^itra- 

 gin." A Xew Jersey company sends out a culture known as 

 " Earmogerm," which is also a jelly-like material. The writer's 

 recent experience has been mainly with the latter, and the re- 

 sults have l^een satisfactory. Eidl directions for the use of cul- 

 tures accompany every package, and these should be exactly 

 f(jl lowed. 



Diseases of Alfalfa. 

 The only disease which has been serious in the experiments 

 in growling alfalfa in this State is a species of rust or leaf-spot. 

 This seems to be most likely to affect newly sown areas. The 

 spots referred to are yellow in color. They are likely to appear 

 first on the lower leaves of the plant ; but in cases of bad infec- 

 tion the trouble rapidly spreads from leaf to leaf, and the entire 

 foliage of the plant soon becomes yellowish in color and the 

 leaves begin to fall. If the disease is allowed to take its natural 

 conrse the plants, especially if young, are greatly enfeebled. 

 Grasses and clovers under these conditions in many fields will 

 be likely to displace the alfalfa. 



