Managing an Aging Norway Maple with Basal Canker and Decay

Condition Assessment

An 80-year-old Norway maple in eastern PA has lost bark on one side (3x12 ft), rotting surface roots, mushrooms under bark, and 1/3 of branches budless. This indicates advanced Cytospora canker and heartwood decay (hollow). The tree is nearing end of life.

Supportive Care

Water deeply weekly in drought. Fertilize with 13-13-13 (2–4 lbs/inch diameter) spring/fall. Prune dead branches in early spring. Reduce salt runoff. These may prolong life but won't reverse decay.

Wound Management

Do not paint wounds—it slows callusing. Cut loose bark to deter insects. Spray exposed area with borer preventive insecticide (lasts ~3 months). Consult an arborist for structural risk assessment.