Elongate hemlock scale found in Oregon

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Elongate hemlock scale found in Oregon

Post by Lucas » Wed Jan 02, 2019 12:49 pm

http://www.hoodrivernews.com/news/2018/ ... ZIsqNQZwQ8

How you dispose of your old Christmas tree this year could make a difference in whether a newly arrived tree-killing insect pest is able to spread into Oregon forests.

According to Invasive Species Specialist William Wyatt at the Oregon Department of Forestry, throwing your old Christmas tree into the woods or leaving it in your yard may spread the elongate hemlock scale (Fiorinia externa).

Williams said this insect arrived in Oregon this fall on Christmas trees brought in from North Carolina. The Oregon Department of Agriculture found the pest and ordered the infested trees destroyed, but not before some had been shipped to big box stores along the West Coast.

The fear is that when the Christmas trees are left for weeks or months in a yard or dumped in a park or the woods, eggs laid on them will hatch and the pest may escape into nearby trees.

If the elongate hemlock scale does get established here, it could be bad news for the state’s timber economy, according to a department press release. The pest attacks not only hemlocks, but several conifer species native to Oregon such as true firs, spruce, and Douglas fir. The scale feeds on the underside of the needles, creating a yellowish-brown waxy layer that is present year-round.

Williams advised that people inspect trees obtained at “big box” stores before disposing of them. Email the Oregon Department of Forestry’s Forest Health Unit at wyatt.williams@oregon.gov if you suspect you have found the elongate hemock scale. It may be safest to cut up such trees and place them in garbag bags for disposal in a closed container.
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Re: Elongate hemlock scale found in Oregon

Post by JHarkness » Wed Jan 02, 2019 1:43 pm

Now this little freaking monster is in Oregon too? I am so disgusted with people's negligence on this pest, it was introduced multiple times along the east coast on nursery stock from Asia and it is still being introduced on nursery stock elsewhere evidently, this has to stop. Like the article says, it doesn't just affect hemlock, it can effect practically all hemlock, spruce and fir species native to North America and is capable of causing at least some mortality in all species.

I haven't posted about the pest here in a while, but I've lately been working on establishing a database of sites in northeastern New York State with the pest to hopefully get the DEC involved with management of it and as a consequence I believe I located one site in the Adirondack Park with it, however it was on private property and I wasn't able to check the trees up close. I can't tell you the arguments I had to get into with people from the DEC for them to even acknowledge that it is a problem, so it is apparent that they're not going to realize it on their own and I fear the case is the same in other states. Even though HWA causing higher mortality rates of eastern and carolina hemlocks, I consider EHS much more of a threat as there has been so little research done on it, it is becoming apparent that it is likely more widespread, it is much more difficult to treat chemically and hardly anyone even knows about it, and a lot of the people I've met who do know something about it are convinced it isn't a threat. I am afraid that even with proper treatment of HWA, EHS is going to be the death of at least the eastern and Carolina hemlocks unless people can get their acts together and see it for the destructive pest it is.

On the bright side, maybe the introduction of EHS to Oregon will prompt a nationwide response to it and something can be done. That said, if ANYONE with NTS has seen this pest on any hemlock, spruce or fir in North America, please report it to whatever organization is necessary, it needs to be stopped, State conservation agencies shouldn't let it run free and continue spreading anymore.

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Re: Elongate hemlock scale found in Oregon

Post by dbhguru » Thu Jan 03, 2019 10:38 am


It is well acknowledged and understood here in Massachusetts. While Mass DCR is guilty of its blind spots, I think we're far ahead of NY's DEC.

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Re: Elongate hemlock scale found in Oregon

Post by Don » Fri Jan 04, 2019 4:09 pm

It would seem to me to be economically infeasible to transport Christmas trees from North Carolina to Oregon...I know of no better selection of Christmas tree species than Oregon's forests have. Sort of like 'taking coal to Newcastle'...that said, controls over such interstate commerce should in any other administration, relatively easy to instate.
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