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Wreath pests (copy)

The Wisconsin Department of Agriculture, Trade and Consumer Protection says elongate hemlock scale attacks more than 40 species of conifers and feeds on the underside of their needles, sapping them of nutrients. They secrete a brown, hard, waxy covering that protects them and spreads as other generations hatch. 

State agencies are urging Wisconsin residents to burn or bag and throw away holiday decorations that show signs of an invasive insect that could threaten local forests or Christmas tree farms.

Elongate hemlock scale, an armored insect native to Asia, feeds on hemlock trees as well as other conifers like spruce, according to the Wisconsin Department of Agriculture, Trade and Consumer Protection. State inspectors found the insect on decorations such as wreaths, swags, boughs, evergreen bough arrangements, hanging baskets, porch pots, mugs and sleighs sold in chain stores across Wisconsin this holiday season.

Wisconsin Department of Natural Resources pest specialist Michael Hillstrom said many hemlock trees grow around Wisconsin Dells and could be at risk.

“It would definitely be a concern, you know, in particular in some of those areas that are pretty much only hemlock,” he said.

Sauk County Forester Paul Kloppenburg said only small pockets of the county have hemlocks, but white spruce is native and common here, as well as other conifers.

While the pest has not been found in Wisconsin’s forests or Christmas tree fields yet, disposing of infested materials improperly could allow EHS to establish itself. Brown spots, also described as a scale, on evergreen needles indicate its presence.

State officials say residents should dispose of infested greenery by bagging it and putting it in the garbage or by burning it. It should not be composted or put out for city brush collections.

Baraboo allows certain types of outdoor open burning, including untreated, unpainted wood from 8 a.m. to 10 p.m. on even-numbered days.

Hillstrom said Christmas trees still can be put out on curbs, as there’s “no real concern” with the invasive species on them. Baraboo Street Superintendent Tony Gilman said collections have been going as usual, because the department doesn’t collect any holiday decorations except trees.

Christmas Treeland owner Suzanne Dohner said she’s not concerned about the insect as it’s not in the area yet and might not be able to flourish in a Wisconsin winter.

However, Hillstrom said most insects like the EHS are only slowed down by sustained subzero temperatures, “which we really just don’t get those stretches much anymore.” He said they can be particularly damaging to trees in areas that haven’t dealt with them before.

“The trees don’t know what to do with them, basically. There’s no history,” he said. “On top of that, where you would normally have predators and stuff like that that would normally eat them, these insects that are coming from somewhere else in the world, they don’t come with their predators.”

If consumers see anything suspicious on products they buy, they should notify the Wisconsin Department of Natural Resources or state agriculture department. Hillstrom also recommended consumers be careful about what they purchase and consider its place of origin.

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Baraboo News Republic reporter