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The Dept. of Forests, Parks and Recreation is asking the public to be on the look out for Hemlock Woolly Adelgid and report suspected sightings.

Hemlock Woolly Adelgid is a very small, non-native insect that damages and kills forest and ornamental hemlock trees. It feeds by inserting a long stylet (tube) through the base of the needles, into the twig and sucking food from the tree's storage cells.

Eastern Hemlock needles are dark, shiny green, with two white lines on the·underside and.are about 1/3 to 2/3 of an inch long. The bark of older trees is gray to brown and often deeply furrowed. Hemlock occupies an important ecological niche in eastern forest ecosystems; providing shade to cool streams and winter shelter for animals. Hemlocks are greatly valued as ornamental and landscape trees.

Local trees are not resistant and there are few natural enemies of this destructive insect. Feeding causes needles to dry out and drop prematurely. Tree mortality may occur in four to six years, although some trees have survived with sparse foliage for more than ten years. Infested areas have experienced extensive
decline and mortality of both forest stands and urban/suburban landscape hemlocks.

The most obvious sign of Hemlock Woolly Adelgid is the white, woolly mass found on the underside of twigs at the base of needles. The masses often look like the cottony tips of Q-tips. More established infestations may feature thinning branches and grayish-green needles.

Suspected infestations should not be moved, but reported to the Department of Forests, Parks and Recreation at 802-241-3606.

Citizens can help slow the spread of Hemlock Woolly Adelgid by accepting only uninfested planting stock. Before purchasing trees, ask where they came from and whether or not they are permitted.

Many new infestations are located near bird feeders and bird baths. The adelgids are most likely to hitch hike on birds between March and July. Taking feeders and baths down for this period when spring food sources are becoming available will have minimal impact on birds but, may be effective in slowing the movement of Hemlock Woolly Adelgid.

Introduced from Asia, where it does little harm, Hemlock Woolly Adelgid was observed in Virginia in the early 1950's and has now spread to sixteen states from Georgia to Maine. In recent years, there have been isolated introductions of infected nursery stock in Vermont that were quickly discovered and eradicated.

In 2007, Hemlock Woolly Adelgid was found on mature, native trees in Vermont for the first time, prompting officials to ask the public to help watch for the intruder.

For more information or to report a suspected sighting, contact the Department of Forests, Parks and Recreation at 802-241-3606.