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Aspen Pruning Wounds Bleeding: Normal Spring Response

Aspens trimmed to the branch collar in late winter/early spring bleed water heavily. This is normal high sap flow. Spray wounds with Merit (imidacloprid) to deter insects attracted to sap. Do not apply wound dressings—they slow healing. Bleeding stops as weather warms. Proper pruning cuts just outside the collar promote fastest closure.

Care for Bleeding Cuts

Apply systemic insecticide to wounds.
Avoid pruning paint or sealants.
Monitor for insect activity.

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