COLOKADO PLAN'r DISEASES 
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Stem Blight (Pseudomonas pisi) (63) — This is a bacterial disease 
affecting both field and garden peas. It first made its appearance in 
1915 in the San Luis Valley and Northern Colorado where it caused 
much loss. Since 1919, however, the disease has not occurred in 
sufficient abundance to produce a great amount of injury. 
Stem blight is characterized by a watery olive green to olive ’ 
brown color of the stems and by yellowish and watery appearing 
leaflets. 
The bacteria causing stem blight gain entrance to the plant 
thi'ough breathing pores or mechanical injuries. Avoid injuring the 
plant by harrowing or other means of cultivation. 
Some varieties of peas are more resistant than others and if the 
disease again becomes abundant it would be well to select the most 
resistant kinds. Late planting is also said to reduce the amount cf 
the disease. 
Millet smut on proso millet. (Original in Colorado Experiment Station Bulletin 242, by Vasey. ) 
