ALFALFA 357 



disease was first observed in Ecuador, but has recently 

 been found in Germany, England, California, Oregon 

 and Arizona. 



Bacterial stem-blight of alfalfa caused by Pseudomonas 

 medicaginis has recently been described from Colorado 

 and neighboring states. This disease attacks the stems 

 primarily, usually causing a linear yellowish to blackish 

 discoloration down one side of the stem through one or 

 more internodes. Sometimes the disease extends to the 

 crown, destroying the buds and eventually the plant. 

 The disease is confined almost wholly to the first cutting, 

 which may be seriously injured, but the subsequent cut- 

 tings are almost unaffected. Few plants are killed the 

 first year, but thereafter the loss is greater so that in 

 three or four years the stand may be ruined. Cutting 

 the stubble very short in early spring as soon as the first 

 damage is over has been recommended. This will remove 

 any diseased portions which may infect the new growth, 

 and besides removes the weakened frost-injured shoots 

 which seem particularly liable to the disease. Hardy 

 varieties which escape winter injury are likely to prove 

 less subject to the disease. A very similar disease also 

 occurs in Virginia and Maryland. 



The leaves of alfalfa are attacked by various fungi. 

 Most common is Pseudopeziza medicaginis which causes 

 small dark brown spots on the leaves. When very abun- 

 dant, there is considerable shedding of leaflets. 



At the New Jersey Experiment Station comparative 

 chemical analyses were made of healthy and diseased 

 plants of the third cutting. The healthy plants showed 

 10 per cent more fat, 12 per cent more protein and 18 per 

 cent more fiber than the diseased, and were richer in car- 

 bohydrates by 11 per cent. 



