Spruce bark beetle activity has declined in many areas of the state since 2009, but is still showing a presence in Southeast Alaska and may be increasing in some areas.
The U.S. Forest Service mapped the 2010 spruce beetle mortality at around 78,000 acres for the state, with only 2,900 acres of that in Sitka spruce in Southeast Alaska. The beetles on 1,250 of those Southeast acres occurred along the outer coast from Cape Spencer at the southern tip of Glacier Bay National Park to Icy Bay. Eight hundred of the remaining acres were mapped south of Petersburg and 850 acres along Lynn Canal north of Juneau.
The spruce beetle has had outbreaks before, notably in the Kenai Peninsula just over a decade ago. There have also been past outbreaks near Haines, Dall Island and along the Taku River.
Mark Schultz, Forest Service entomologist for the Alaska Region, said major outbreaks are not currently on the rise within the state but conditions must be watched.
He said outbreaks typically only flare up if there’s a lot of downed material and warm summer temperatures among other conditions.
Schultz said beetle outbreaks can still be a concern, as they can produce dead trees. He said the beetles in Southeast Alaska mainly feed on Sitka spruce while those in other areas of the state go for black, white or Lutz spruce.
He said many such trees, however, can be in remote areas and so may not be marketed anyway.
• Contact reporter Jonathan Grass at 523-2276 or at firstname.lastname@example.org.
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