AbstractThe recent outbreak ofLophodermiumneedlecast in North America first appeared in 1966 in forest nurseries on red pine (Pinus resinosa) and Scotch pine (P. sylvestris). Dispersal of infected nursery stock throughout North America has created a serious needlecast problem in Scotch pine Christmas tree plantations. Two biotypes ofL. pinastriare present. The pathogenic strain may be a recent introduction. The fungicides maneb and chlorothalonil are being used for control.
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