Infected trees can decline slowly over several years or die within weeks of the first symptoms, depending on the size and health of the tree. The plant can be girdled as the fungus moves up the stem. Trees weakened by root rots are easily pushed over by heavy winds. The most common root rot pathogens of apples in Ontario are species of Phytophthora. Typical symptoms of a root disease are apparent on infected plants. Infected trees can decline slowly over several years or die within weeks of the first symptoms, depending on the size and health of the tree. The plants also decline in vigor and suffer additional damage from other pathogens or insect pests. But symptoms are more likely during stress periods of low rainfall. Phytophthora spp. Most actively growing trees tolerate a certain amount of root and crown rot, and may limit the advancement of the disease for a short while. Improve water drainage. Scouting Notes
Period of Activity
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