New bark beetle threatens Washington forests
Five years ago, when entomologist Todd Murray received a call from a landowner in Underwood whose ponderosa pine trees were dying, he wasn’t surprised. The trees had been stressed by a nearby fire, a situation that commonly results in a flare-up of bark beetles that can kill the trees. But the calls kept coming.
“People were saying things like, ‘I’ve lived here all my life and have never seen pine trees die like this,’” said Murray, WSU Extension director for Skamania County. “The situation has worsened since then.”
At the time, Murray didn’t know that the culprit was a new pest on the scene, the California fivespined ips (CFI), or Ips paraconfusus.
This summer, WSU Extension, along with the Washington Department of Natural Resources, Oregon Department of Forestry, Oregon State University and several other agencies and nonprofits, begins a coordinated effort to help landowners respond to emerging forest health concerns like CFI outbreaks with training, outreach materials and on-the-ground treatments.
Attacks between the urban and wild
The new beetle is showing up in the wildland-urban interface, where areas between unoccupied land and human development are at risk for wildfires. In Washington, beetle damage thus far is limited to the Columbia River Gorge area. However, the beetle has been confirmed as far north as Fort Lewis.
The beetle favors the green, freshly broken branches of many species of pine, including ponderosa, sugar, western white and lodgepole.
The male bores into the tree to create a nuptial chamber underneath the bark and then emits pheromones to attract females. Females, usually three at a time, come to mate and then carve out an egg gallery where larvae hatch and feed on the cambium, a secondary protective layer under the bark.
“A healthy tree can easily spit out this (kind of attack) with pitch,” Murray said, but this natural defense doesn’t work when the trees are stressed or the beetles are too numerous. During an outbreak, beetles actually coordinate their attack to overwhelm tree defenses.
Climate change or forest health?
It’s unclear whether CFI has newly expanded its range north from Oregon and California or if it’s been in Washington historically and gone unnoticed. Until 2010, when the pest was officially documented in Washington, it hadn’t been found beyond the northern reaches of the Willamette Valley in Oregon.
The beetle may have moved northward as a result of climate change, but Murray suspects it is more likely that the insect has reclaimed an existing range that until now hasn’t had the right set of conditions to support the outbreaks.
“Bark beetles are there all the time,” Murray said. “It’s a forest health issue when there are population flare-ups.”
Forests stressed by drought, fire and storm damage are susceptible to insect and disease damage. Ironically, the recent outbreaks may be due partially to forest health improvements that have resulted in a greater number of older trees, which beetles prefer.
Mature trees overwhelmed by CFI are easily identified by their red tops. The beetle tends to infest the tops of trees where branches are more likely to be broken by wind and where bark is thinner.
An infestation turns the needles pale green, then orange and finally reddish brown. Mature trees may recover, but young trees that are completely red are unlikely to survive.
Other signs of infestation include numerous exit holes in the bark and accumulations of reddish brown bark dust.
Adding insult to injury, adult beetles can introduce a fungus that kills tree tissue in the attacked area and further weakens the tree. The fungus stains the wood blue.
During an outbreak, the advice is to do nothing. From February through September, avoid pruning or creating any slash piles that could harbor the pests. Early season pruning especially can exacerbate the problem.
The recommended window for pruning, thinning, tree removal and slash management is between October and January, when the insects are dormant.
While commercial repellant lures have been developed for other bark beetles, none are effective for this species. The best medicine is prevention — improving and maintaining overall forest health.
Global teamwork will make world food supply safer
A new global food safety partnership will provide technical support for the food industry through research, scholar exchange, collaborative teaching and outreach activities.
The Washington State University/University of Idaho School of Food Science and Seoul National University Department of Food and Animal Biotechnology (Food Science) recently signed a memorandum of understanding to create the Center for Applied Food Safety and Processing. It formalizes collaborations that started in 1999 between the Korean university and WSU.
The co-located center will address global food safety and processing issues to help ensure a safe, wholesome and sustainable worldwide food supply through research and training.
“As much as possible, the teaching will be delivered in a ‘train-the-trainer’ format,” said Barbara Rasco, professor and interim director of the U.S. school. “This will develop the capacity to continue training on a long-term basis. The center also intends to bring more academic institutions on board.”
Dong-Hyun Kang, professor and director of the Korean department, will travel to the United States in December to help develop programs for the new center.
Warning: Washington forests at risk
Where forests are overcrowded, insect outbreaks, disease and wildfires are more severe and extensive. In Washington, insect and disease damage doubled between the 1980s and the 2000s from 600,000 acres to over 1.2 million acres of the total 22.4 million acres of forestland.
Today, four counties bear the bulk of this forest health burden. In 2012, Public Lands Commissioner Peter Goldmark issued a Forest Health Hazard Warning for parts of Okanogan, Ferry, Klickitat and Yakima counties to raise awareness and encourage landowners to learn more about forest health and reducing tree densities to appropriate levels.
Source: Forest Health Highlights in Washington—2013, Washington State Department of Natural Resources Forest Health Program, March 2014.
For related information in the WSU Extension online store, check out the following options:
Forestry Education and Assistance for Washington Forest Landowners
Diversifying Forest Structure to Promote Wildlife Biodiversity in Western Washington Forests
Assessing Tree Health
Pacific Northwest Insect Management Handbook
Women’s Leadership Symposium 2014:
Redefining Body Image
The 2014 Women’s Leadership Symposium, “Redefining Body Image,” will be held from 9 a.m. to 4 p.m., Friday, Oct. 3, in Ensminger Pavilion on the WSU Pullman campus. This full-day workshop will empower participants to live life by intentional design. Register now to create a blueprint for conscious living by exploring how to develop courageous relationships, discover beauty within yourself and in the world, and share wisdom through skillful actions.
Symposium facilitator Krista Petty, M.A., is an international life skills enhancement coach and trainer who has created workshops in leadership, personal mastery, individual effectiveness and integral learning. Krista also co-developed with Dr. Kim Kidwell the popular University Common Requirements course Human Development 205, Developing Effective Communication and Life Skills.
Registration for the symposium is $85 per person, or $40 for students.