Oregon's forests could be at risk from an invasive insect species if Christmas trees from North Carolina and sold at big box retailers aren't properly disposed of this holiday season, state officials said Friday.
The California Department of Food and Agriculture identified the presence of the insect elongate hemlock scale on trees this fall and sent word out to other states.
Oregon officials then contacted the North Carolina business that shipped the trees and requested the potentially infected trees be recalled or destroyed locally.
This included about 8,000 trees delivered to the West Coast, but it's unknown how many were in Oregon, said Danny Norlander of the Oregon Department of Forestry.
Norlander said no infected trees have been positively identified in Oregon, but this is the first instance of even the possibility of elongate hemlock scale appearing in the state.
The insects have been identified in other states on other Christmas products shipped from North Carolina. State officials in Wisconsin, for example, are advising residents to burn wreaths and other evergreen decorations, or bag them and take them to a landfill.
Norlander said burning the trees would work, but if that's not possible, cutting it into smaller pieces and bagging it is also a safe disposal method.
The Oregon Department of Forestry is advising people who bought a tree from a big box store this year to inspect it before throwing it away. The fear is that if a tree is left in a yard for weeks, or dumped in the woods, the eggs may have an opportunity to hatch and infect nearby trees.
The elongate hemlock scale 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.
This impact could be a particular concern from Oregon's Christmas tree farms, the nation's largest producer.
"You want the trees to look healthy, you want the trees to look nice, and if they’re sick from scale insects, that’s an issue," Norlander said.
The bug targets hemlocks and several conifer species native to Oregon, including firs, spruce and Douglas fir.
Jim Gersbach, spokesman for the Oregon Department of Forestry, said the bugs are hard to spot because they are relatively small, don't make noise and aren't immediately identifiable as insects.
"They just sit there quietly doing damage to the tree," he said.
The bug is not native to the Pacific Northwest and, in the United States, is seen in East Coast states. It's believed that the insect was incidentally imported to the U.S. from Japan in the early 20th century.
One way to avoid introducing invasive species to an area is to always buy locally produced plants, trees and firewood.
"It’s best to buy local," Norlander said.
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