Texas,Oklahoma and Kansas winter temperatures and rainfall,and summer occurrence ofPuccinia graminis tritici in Kansas,Dakotas, Nebraska,and Minnesota

Temperature and rainfall data for the winter months December through March in Texas, Oklahoma, and Kansas were related to subsequent summer wheat stem rust severity in Kansas, Nebraska, the Dakotas and Minnesota for the period 1904–1960.Kansas winter temperatures and rainfall data were not related to rust severity in the states northward.Although precise weather rules for rust epiphytotics were not found,these preliminary analyses indicated that there might be a causal relation between March precipitation in Texas and Oklahoma and subsequent wheat stem rust outbreaks in May in Kansas and June and July in Nebraska, the Dakotas and Minnesota.