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Identifying and Controlling Obscure Scale on Pin Oak Trees

A Hidden Pest on Pin Oaks

Obscure scale females attach to twigs, suck sap, and secrete a waxy coating that matches bark color, making them hard to see. Infestation causes gradual weakening and dieback.

Treatment

Apply horticultural oil to suffocate scales.
Follow with insecticide when immature crawlers emerge in spring.

Virginia Tech factsheet: www.ext.vt.edu/departments/entomology/factsheets/obsscal.html. If comfortable climbing and spraying all branches, you can DIY; otherwise hire a professional.

About Gardening: Ming Tree (Polyscias) Sticky Leaves: Scale Insects; Black Scaly Substance on Willow: Soft Scale Infestation; Cottony Scale on Mimosa: Identification and Systemic Control; Scale Insects on Ficus Tree: Identification and Treatment; Possum in the Yard: Harmless Scavenger or Nuisance?; Sabal Palmetto Scale Control: Horticultural Oil and Predators; Wax Scale on Boxwood: White Bumps With Red Undersides—Spray Oil Now, Carbaryl in April; Obscure Scale on Oak: Oil Sprays and Monitoring; Euonymus Scale on Pachysandra: Identification and Control; Controlling Euonymus Scale: Pruning, Systemics, and When to Replace

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