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Scale Infestation on Raywood Ash: Blackened Branches Explained

Black, Brittle Branches on Raywood Ash? It’s Scale Insects

The dead, blackened branches and heavy ant activity on your mature Raywood ashes point to scale insects. Scales suck sap and excrete honeydew, which grows sooty mold (the black coating). Ants farm the honeydew.

Treatment

Apply Bayer Advanced Tree and Shrub Insect Control as a soil drench. Roots translocate it to twigs; scales die when they feed.
Takes 2+ weeks to reach canopy top, depending on tree height and weather.
Reapply next spring for continued protection.

The black sooty mold will weather away once scales are gone.

Trees: Peach Tree Borers: Gummy Sap and Grubs at Base; Raywood Ash Slow Growth: Addressing Root Girdling and Fertility; Identifying and Treating Scale on Aspen Trees; Ash Tree Roots Lifting Driveway: Keep or Remove?; Raywood Ash Leaf Drop in Phoenix: Normal Winter Dormancy; Planting and Pruning Raywood Ash: Avoid Topping!; Raywood Ash Failure: Black Heartwood Doesn’t Mean Disease; Rescuing Heat-Stressed Raywood Ash Trees Planted in Summer; Two Trees with Distinct Problems; Raywood Ash Basal Sprouts: Normal, Not a Root Problem

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