Root Rot (Armillaria)
Armillaria spp.
1 host plant · Fungal
Last updated
This profile synthesizes data from multiple published sources. Expert field review is in progress.
Armillaria root rot affects many plants in cool, moist forests, causing decline and death through root decay. Remove infected plants and stumps. Improve drainage where possible. Select resistant species for affected sites. Monitor for symptoms and remove infected trees promptly. Proper drainage and good site selection are critical to prevent root disease problems. Monitor plants for early signs of decline or wilting.
Root rots thrive in waterlogged soil, so drainage is your most important intervention. Avoid overwatering and ensure the planting site drains well. Remove severely affected plants to prevent spread to neighbors through root contact or contaminated soil. When replanting, choose resistant species or improve soil structure before putting anything back in the ground.
Quick Reference
Management
Root infection year-round but active Oct–May. Symptom expression 2–10+ years post-infection. Trees may show no symptoms for years. Sudden collapse during drought stress. BBCH 10–89.
Root contact with infected mycelium and rhizomorphs. Cool, moist soil conditions (40–60°F, Oct–May) most favorable. Stress and poor vigor increase susceptibility. Waterlogged soils accelerate disease.