Pests & Diseases Asian Longhorned Beetle Bagworms, Webworm Beech Bark Disease Cherry Scallop Shell Moth Cicades Common Oak Moth Emerald Ash Borer Fungal Leaf Diseases Gypsy Moth Hemlock Woolly Adelgid Oak Sawfly Pine Shoot Beetle White Oak Defoliation
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Contact: Stephanie Downs 740-589-9914
Hemlock Woolly Adelgid, Adelges tsugae is an introduced pest from Asia that is a threat to Eastern Hemlock, Tsuga canadensis and Carolina Hemlock, Tsuga caroliniana in eastern North America. White cottony sacs found at the base of the needles are good evidence of the Hemlock Woolly Adelgid. The Adelgid uses these sacs to protect itself and its eggs. These sacs, resembling the tips of a cotton swab can be seen from early winter till early summer but are most prominent in early spring. This small, less than 1/16” insect, sucks sap from young twigs which retards or prevents tree growth causing needles to discolor and drop prematurely which severely affects plant health. Defoliation and tree death can occur within 4 to 10 years of infestation. Hemlock Woolly Adelgid has infested eastern states and threatens the ecological balance that exists in the Eastern Hemlock forest. The first discovery was in a landscape setting in Lake County in 2002. Since then, it's been discovered in several additional counties throughout the state in landscapes or on nursery stock. All of these discoveries eradicated by the Ohio Department of Agriculture. Surveys in natural stands of hemlock have been conducted by the Ohio Division of Forestry since 2007. Until 2012, no infestations were discovered in natural stands. In January of 2012, HWA was found for the first time in a natural stand. Since then, additional populations have been found in other counties in Ohio.
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