Pine Tree Black "Fungus": Likely Sooty Mold from Insect Honeydew

Reassessing the Black Coating

Black, mold-like growth on pine trunks/branches from ground up, with bark peeling, on 8–20 year old trees is likely sooty mold—not a primary pathogen. It grows on honeydew from insects feeding higher up (aphids, scale, adelgids) on pines or nearby trees. Wind carries droplets onto pines.

Diagnostic Test

Check pines and surrounding trees for:

• White woolly adelgids on pine bark/buds.
• Scale on branches.
• Aphids on new growth.

Management

• If insects found: treat with horticultural oil or imidacloprid drench.
• If no insects: mold is from external source; will diminish when source dries up.
• Bark peeling may be natural exfoliation or separate issue—send photo to byrd58@bellsouth.net ("allexperts") if unsure.

Sooty mold itself doesn't harm pines—it's a symptom, not a disease.