WSDA: Check Your Trees, Wreaths For Pest

The State Department of Agriculture is asking Washingtonians to check their Christmas trees, wreathes and other purchased holiday greenery for invasive species.  Last week WSDA confirmed elongate hemlock scale, Fiorinia externa, on out-of-state sourced holiday greenery.  The Department said the invasive species is a flattened, oval shaped insect with a light yellow-brown to brownish-orange waxy cover, with the waxy covers observed on the underside of the needle surface as well as on new cones.  In some situation, these strands may make infested needles look white.  

Anyone who thinks they have an infested tree or greenery is asked to cut up the material, double-bag the pieces and dispose of it in the trash.  Then you are asked to e-mail the WSDA.

“If you find these pests on your trees, wreathes or other holiday greenery, please report it to us and dispose of them immediately,” Benita Matheson, plant services supervisor said.

Elongate hemlock scale (EHS) is an exotic scale insect that prefers hemlock, spruce and fir, but will also feed on cedar, pine and yew.

“Proper disposal goes a long way in preventing the introduction and spread of invasive species that could hurt our environment and cause millions of dollars in damage to our economy,” said Justin Bush, executive coordinator of the Washington Invasive Species Council. “Do your part to protect the state you love.”

Residents can prevent introducing invasive species from out of state, such as elongate hemlock scale, by buying a locally grown tree and cut greens, which also supports the local economy.

According to the WSDA, this armored scale insect is thought to have been unintentionally introduced into the United States from Japan.  It was first observed in Queens, New York in 1908.  It was most recently detected in Washington on Christmas trees from North Carolina in 2019, but is not known to be established anywhere in Washington.

Currently the pest is found in Connecticut, Maryland, Massachusetts, New Jersey, New York, North Carolina, Ohio, Rhode Island, and Virginia.

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