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Pine with Black Sooty Mold on Needles: Scale Insect Infestation

Long-needle pine (possibly Scotch) in upstate NY has dying needles/branches and black substance on branches. The black is sooty mold growing on honeydew from scale insects.

Diagnosis & Treatment

Scales suck sap → excrete honeydew → mold grows on it.
Control scales → honeydew stops → mold weathers off.
Apply imidacloprid soil drench (Bayer Advanced Tree & Shrub Insect Control).
Systemic moves to needles; scales die feeding.

Available at garden centers. One treatment lasts season. Identify scale type (pine needle scale, etc.) for timing if using horticultural oil instead.

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