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Fir Tree Infestation: Aphids/Scale, Sooty Mold, and Systemic Treatment

Diagnosis: Sucking Insects + Sooty Mold

Black sticky patches = honeydew from aphids or scale insects. Black sooty mold grows on honeydew. Wasps/ants attracted to sugar. Ladybirds = predators (good sign).

Systemic Treatment

Bayer Advanced Tree & Shrub Insect Control (imidacloprid soil drench):

Applied to soil → roots absorb → moves to foliage.
Insects die when feeding on sap.
Controls aphids, scale, adelgids, borers.
Available at garden centers.

Product info: Bayer Advanced

Alternative: Contact Spray

Horticultural oil or insecticidal soap for immediate knockdown—requires thorough coverage, repeats needed.

Cultural Note

Healthy trees tolerate minor infestations. Fertilize appropriately, water deeply, avoid stress.

Conifers: Pecan Tree Black Nuts and Spider Webbing: Phytophthora Root Rot and Harmless Barklice; Tree Black Growth and Sap: Gummosis from Borers or Black Knot Disease; Deodar Cedar Decline: Water, pH, and Pest Investigation; Black Knot Disease on Plum: Pruning and Fungicide Protocol; Hemlock Woolly Adelgid on Fir: Systemic Treatment; Saving a Fir with a Dead Top; Black Mold on Young Tree: Aphids and Sooty Mold Fix; Black Sticky Residue on Patio: Sooty Mold from Aphids or Scale; Douglas Fir Co-dominant Leader Decision; California Black Oak: Majestic Native Tree for Wildlife and Timber

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