Red Maple Limb Failure and Internal Decay

An 8-year-old red maple lost a large limb (12-inch diameter) that tore bark to the ground, revealing a softball-sized black decay pocket. The owner sealed the wound; the tree still blooms. He asks whether to keep it.

Decay Fungi & Tree Safety

Decay fungi enter through wounds and hollow out heartwood over years without killing living cambium. The tree can survive many more years if the decay hasn't progressed into upper trunk and major limbs. Test by checking if wood at the break is soft or hollow.

Hazard Assessment

• If decay is advanced in upper trunk/limbs, large branches may fail.
• If the tree could hit a structure, it's a hazard tree—consult a state forester.
• If no target, it may be kept with monitoring.

Health Improvement

Fertilize with 10-10-10 at 1 lb per inch of trunk diameter, scattered and watered in (or before rain) to boost vigor.