SALEM, Ore. — The Oregon Department of Agriculture’s (ODA) Nursery and Christmas Tree program staff detected the insect pest, elongate hemlock scale (EHS), on Christmas tree products sold at big box stores in Oregon while performing routine inspections. The stores purchased the items from out of state suppliers. ODA ordered stores immediately pull products from shelves and to destroy or send the infested items back. ODA has confirmed that similar products were also found in Washington State and were likewise rejected by Washington State agricultural officials.
ODA encourages the public to take a moment to check Christmas tree products before taking them home and to avoid the risk of “packing a pest” by buying locally produced products. To date, ODA has only found EHS on Frasier fir Christmas trees, wreaths, and Christmas arrangements. In each incident, the products originated from out of state. Although EHS is not established in Oregon, it has the potential to establish and attack Oregon native conifer species, western hemlock, and mountain hemlock. This pest is also known to infest Douglas-fir, spruce, fir, and pine species – making this a concern for Oregon’s Christmas tree farms. Oregon is the nation’s largest producer of Christmas trees.
EHS feeds on the undersides of needles and drains fluid the tree needs for growth. It can result in a yellow-brown film on needles and cause them to drop from the tree. EHS spends most of its life in an immature state, only 1.5mm long, fixed under a brownish-white waxy layer on the underside of the needles where it feeds.
If you believe items, you purchased have EHS please report to the Oregon Invasive Species Hotline at https://
For more information on what to look for and how to properly dispose of your wreaths and trees, please check out this one-page prepared by our partner the Oregon Department of Forestry.