Tree disease problems

Phytophthora root

10. Phytophthora root

This fungus disease causes root rot and stem cankers on many landscape trees and shrubs. Phytophthora is most prevalent on clay soils that are poorly drained and on sites receiving excessive irrigation. Fungicide treatments are available to suppress this disease. Careful selection of plant species for sites prone to root rot and judicious irrigation are also keys to managing this disease.