Black Knot

Brian Hudelson, UW-Madison Plant Pathology, UW-Extension Revised:  5/1/2010 Item number:  XHT1056 What is black knot?  Black knot is a disfiguring and potentially lethal disease of trees and shrubs in the genus Prunus.  This genus includes stone fruits such as wild, fruit-bearing and ornamental plums and cherries. What does black knot look like?  During the first […]

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