Cutting a Surface Root on Mature Purple Ash for Patio

Best Practice

Make a clean cut (not a shave) to allow the root to seal and resist decay fungi. Shaving leaves a large wound inviting rot.

Impact Assessment

• Cutting one large root may cause some canopy dieback on that side.
• If more than 1/3 of the root zone is severed, the tree may die.
• Roots will regrow under the patio and may eventually crack it.

Mitigation

Fertilize with 10-10-10 at 1 lb per inch trunk diameter to offset stress.