Pruning Mature Locust Trees: Timing, Fertilizing, and Realistic Expectations

Question

Will pruning a 25+ year old locust tree promote new growth on lower limbs?

Answer

No. Pruning stimulates growth at the cut sites (upper canopy), not on bare lower trunks. Locusts naturally shed lower limbs as they mature.

Recommended Care

• Cleaning prune: Remove dead, crossing, or hazardous limbs anytime before leaf-out; September–October is ideal for honeylocust.
• Fertilize: 13-13-13 at 1 lb per inch of trunk diameter, scattered under canopy, watered in.
• Resources: ISA pruning guide | NDSU fertilizing trees

Bottom Line

Accept the tree's natural form. Focus on safety and health, not forcing lower foliage.