Black Film on Hackberry: Aphids and Sooty Mold Solution

Diagnosis

The black, sticky film covering plants, furniture, and concrete under your San Antonio hackberry is sooty mold growing on honeydew excreted by aphids feeding on the leaves.

Effective Control

Apply Bayer Advanced Tree & Shrub Insect Control (imidacloprid) as a soil drench in early spring. The systemic action moves up to the foliage, killing aphids as they feed. One application protects all season.

Why This Works

• Targets the source (aphids), not the symptom (mold).
• Soil application avoids spray drift and covers the whole canopy.
• Residual control lasts through the growing season.

Cleanup

Once aphids are gone, honeydew stops, sooty mold weathers off. Power-wash hardscapes if needed.