ARCATA, California, January 22, 2009 (ENS) – Death rates of old-growth trees in western U.S. forests have more than doubled over the past few decades, and the most likely cause of the trend is regional warming, finds new research to be published Friday in the journal “Science.”

Led by scientists with the U.S. Geological Survey, the research team found that the increase in dying trees has been pervasive. Tree death rates have increased across a wide variety of forest types, at all elevations, in trees of all sizes, and in pines, firs, hemlocks, and other kinds of trees.

Increasing tree mortality rates mean that western forests could become net sources of carbon dioxide to the atmosphere, further speeding up the pace of global warming, the scientists indicate.

Regardless of the cause, higher tree death rates could lead to substantial changes in western forests, said Phil van Mantgem, a USGS scientist and co-leader of the research team.

“The same way that in any group of people a small number will die each year, in any forest a small number of trees die each year,” said van Mantgem. “But our long-term monitoring shows that tree mortality has been climbing, while the establishment of replacement trees has not.”

The result is that forests have begun to lose trees faster than they are gaining them, said van Mantgem, a research ecologist with the USGS Redwood Field Station in Arcata, California.

Dead tree in Sequoia National Park, California (Photo by Nate Stephenson courtesy USGS)

These changes could change the suitability of forests for wildlife species, the scientists suggest.

They ruled out a number of possible sources of the increasing tree deaths, including air pollution, long-term effects of fire suppression, and normal forest dynamics.

Instead, increasing regional temperature was correlated with tree deaths.

“Average temperature in the West rose by more than 1° F over the last few decades,” said van Mantgem. “While this may not sound like much, it has been enough to reduce winter snowpack, cause earlier snowmelt, and lengthen the summer drought.”

The lengthening summer drought could be stressing trees, leading to higher death rates, he said. Warmer temperatures also might favor insects and diseases that attack trees. Some recent outbreaks of tree-killing bark beetles in the West have already been linked to warming temperatures.

“Tree death rates are like interest on a bank account – the effects compound over time,” said Nate Stephenson, also with the U.S. Geological Survey and research team co-leader.

“A doubling of death rates eventually could reduce average tree age in a forest by half, thus reducing average tree size,” said Stephenson, director of the USGS Sierra Nevada Global Change Research Program.

In some cases, increasing tree deaths could indicate forests vulnerable to sudden, extensive die-back, similar to forest die-back seen over the last few years in parts of the southwestern states, Colorado, and British Columbia.

“That may be our biggest concern,” said Stephenson. He worries that the trend observed by the research team is a prelude to bigger, more abrupt forest changes.

Complete findings appear in the article, “Widespread increase of tree mortality rates in the western United States.” Scientists with the U.S. Forest Service, University of Colorado, University of Washington, Oregon State University, Pennsylvania State University, Northern Arizona University, and the University of British Columbia contributed to this research.

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ARCATA, California, April 11, 2008 (ENS) – Dr. James Russell of the Humboldt State University Department of Applied Technology is holding a brick that looks like leftover supplies mashed together after art class, but it could be a great way to repurpose used styrofoam for building insulation.

The idea, originated by Roger Pryor of Bayside Builders, is exactly the sort of thing that Dr. Russell and others behind the GreenLab at Humboldt State hope to see students, faculty and community members working on in the near future.

Dr. James Russell holds a repurposed styrofoam
and concrete block. (Photo courtesy
Humboldt State U.)

So far, the repurposed styrofoam idea looks like it could be useful – the material is relatively light weight and keeps its form when compressed. As far as it”s R-value goes, a measure of the material”s insulation properties, that is yet to be determined in the design and prototyping courses offered by Applied Technology and undertaken in the GreenLab.

The GreenLab is Humboldt State’s newest chartered research institute and Dr. Russell, along with John Ash, architect and head of the John Ash Group and Dr. Susan Higgins, dean of the College of Professional Studies, are welcoming the public to the grand opening next Friday, April 18 from 1:30 to 4:30 pm in Jenkins Hall.

Officially known as the Green Product Design and Development Laboratory, GreenLab grew out of a partnership between the Department of Applied Technology, the John Ash Group and the university”s Office for Economic and Community Development.

That office’s director, Maggie Gainer, says, “The GreenLab adds a new dimension to HSU’s impact on the region’s economy – innovation of green technologies and environmentally sustainable products.”

A unique partnership between Humboldt State and the environmentally conscious business community is emerging.

Gainer says, “I’m excited about the GreenLab’s potential for partnerships with local business and industry.”

The goal for the lab is not only to serve as a think tank, meeting space and research facility but also to bridge the gap between visions for innovative products and market-ready goods.

Russell, whose background includes bachelor’s and master’s degrees in mechanical engineering, worked for Pilkington Glass designing equipment and eventually taking on the roll of environment and safety manager. “It was a glass manufacturer, so safety was paramount. There was never any time for anything proactive, environmentally,” he says.

With the opening of the lab at the end of this week, Russell wants to put the word out to local businesses that seedling ideas for product designs and innovations are the perfect “grist for the GreenLab.”

“Ideally I’d like to have a stack of these ideas for my students to work on,” says Russell.

Already, Applied Technology’s impact on the local community is being felt. Ben Davis, who graduated from the program last fall, designed a heat recuperator for Fire & Light”s three production furnaces. The design has the potential of shaving 30 percent off the company”s $15,000 per month energy bill.

Class and laboratory experiences and face-to-face contact with industry professionals are paying off big for the students. With offers coming in for internships and post-graduation jobs at top construction and manufacturing firms, it is only a matter of time before a graduate of the Applied Technology program comes in with his or her own firm, looking to the GreenLab for help developing the next million dollar idea.

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