Red shoot, caused by the fungus Exobasidium perenne, is a relatively minor disease of the cultivated American cranberry (Vaccinium macrocarpon) and the wild small cranberry (Vaccinium oxycoccus) ...

Affected shoots do not produce flowers but rather are spindly with red or yellow leaves that are slightly more round than typical oblong cranberry leaves. By mid summer the lower surfaces of leaves become covered with white, powdery fungal spores. Shoots wither after the fungus has shed its spores. Diseased shoots break off easily ...

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