Phytophthora Root Rot of Juniper

Disease Information

Phytophthora Root Rot

Symptoms and damage

 Leyland cypress is susceptible to the root-rotting fungus Phytophthora. Root rot is primarily a problem in soils with very poor drainage. Young plants are most often affected. Mature, established trees are seldom affected. Phytophthora species that cause root rot live in the soil and enter a healthy tree through wounds or the succulent parts of small roots. As the fungus destroys the roots, symptoms of distress become apparent above ground. Foliage becomes stunted, sparse, changes color (yellow, purple, tan) and dies. Cankers may be visible at or below the soil line.


 Remove and destroy infected plants including the entire root system. There is no practical chemical control for home gardeners. Improve soil drainage by adding organic material to heavy, clay soils and avoid overwatering. If replanting, do not plant a Leyland cypress or other susceptible species where Phytophthora is known to be present.


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