White Pocket Rot (Piped Rot)
Inonotus dryophilus
50 host plants
Last updated
This profile contains verified disease data from extension databases. Regional field notes and expert review are in progress.
Oak trees develop white pocket rot in heartwood with annual conks on the upper bole near wounds. Inonotus dryophilus enters through pruning wounds and other injuries. Inspect trees for decay to assess stability. Remove affected trees to avoid property damage. Avoid wounding trees and prevent water from sprinkler irrigation contacting trunks.
Reduce moisture around affected tissue by improving drainage and air circulation. Remove rotted material cleanly and dispose of it away from the planting area. Avoid wounding healthy tissue during cleanup, as fresh wounds create new entry points. If the problem keeps returning, evaluate whether the site is too wet or poorly drained for the species you are growing.
Quick Reference
Management
Root infection Oct–May. Symptom expression delayed 3–10+ years post-infection. Progressive internal decay year-round; visible symptoms during heat/drought stress. Sudden decline when roots fail. BBCH 10–89.
Root contact with infected mycelium and decaying wood. Cool, moist soil conditions (40–60°F, Oct–May). Stress factors including drought, poor drainage, wounds, and pest damage increase susceptibility and disease expression.
Cultural Controls
- Irrigation water, especially from sprinklers, should not wet the trunks.
- Inspect trees for decay to assess tree stability.
- Remove affected trees to avoid damage to surrounding property.
- Reference Boyce, J.S. 1961.
- Forest Pathology, third edition.
- McGraw-Hill Book Company.