October 18, 2001
Story ideas for reporters: Investigations using crane range from water works to witches’ brooms
Going up — A key factor in forest growth, and subsequent carbon sequestration, is the way trees take up and give off water. Work at the crane covers this process from below the forest floor to the very tops of the trees. A new project at the crane site is trying to determine the significance of what scientists call hydraulic lift in the root zone. In times of drought, deep roots bring water up to a tree’s fine roots in the top 6 feet of soil where, if conditions are dry, the water can “leak” back into the soil. New findings from work at the crane and other sites have shown that water leaking into the soil could help seedlings, even those some distance from the tree, survive dry conditions, says Rick Meinzer. There also is a hypothesis that the water keeps nutrients soluble so the tree’s fine roots can absorb them. At the crane, Meinzer and co-workers are trying to measure how much water is actually making its way back into the drier surface soil, in!
formation needed by scientists debating the importance of this process.
Rick Meinzer, USFS Pacific Northwest Research Station, 541-758-7798
Other possible contacts: Renee Brooks, Environmental Protection Agency, Corvallis
Barbara Bond, Oregon State University
Tom Hinckley, University of Washington
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Focus on photosynthesis — Because young trees grow faster, it was long assumed that they absorbed more carbon dioxide than old-growth. Projects at the crane site, however, are showing that older forests are vigorously active and store huge amounts of carbon. Researchers interested in photosynthesis, for example, have used the crane to learn that the physiological activity level of conifer needles is higher at the brightly lit tops of trees than at the bottom or in younger saplings that are often in the shade. In other work, scientists learned that photosynthesis occurs year round, the trees don’t go dormant as once assumed. Photosynthesis slows in the winter, down to 40 percent of the rate during the summer, but not because of the cold. Rather it’s a lack of sunlight during dark winter days, according to Bill Winner. If the region should have many more dreary days each year — warmer, wetter winters are an expected consequence of climate change for this region experts s!
ay — then our forests may actually take up less carbon dioxide every year in spite of an atmosphere enriched with growing amounts of carbon dioxide.
Bill Winner, Oregon State University, 541-737-1749
Sean Thomas, University of Toronto, 416-978-1044
Other possible contacts: Jerry Franklin, University of Washington
Thomas Suchanek, Western region of Dept. of Energy’s National Institute for
Global Environmental Change, based at UC Davis
Rick Meinzer, USFS Pacific Northwest Research Station
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Biological firecracker — Each fall the parasitic western hemlock dwarf mistletoe forcibly ejects its seeds — sometimes with enough velocity to travel 50 feet. Once infected, a tree becomes stunted, its branches may deform into bristling growths called witches’ brooms and sometimes it dies. It’s such a problem that timber managers use computers to predict the course of infestations and how much timber might be lost. Thirty percent of the forest around the crane is infested and researchers already have produced information on the basic biology of the mistletoe. A related project now being launched involves the Johnson’s hairstreak butterfly. It’s an elusive upper canopy inhabitant so hard to track that no one can even tell for sure if it is rare or quite common. Dwarf mistletoe happens to be the only thing the butterfly’s caterpillar eats and researchers plan to use the crane to observe caterpillar outbreaks.
Dave Shaw, University of Washington, 509-427-7028
Kristina Ernest, Central Washington University, on sabbatical
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What lies beneath — The key processes resulting in the storage of carbon in an old-growth ecosystem occur below ground, says Jeff Klopatek. Research at the crane shows dramatic root growth: up to 1,000 grams per year per square meter. The root growth means carbon is being gained in the area below the forest floor even though the carbon content of the soil may hold steady. To analyze how root growth changes the nutrient content of soil, nearly 200 soil bags have been buried at the crane. Once riddled with tree roots, the bags are retrieved for processing that involves, among other things, separating and collecting all the roots down to the size of a human hair. Also embedded in the forest floor at the crane site are cylinders to which researchers attach a gas analyzer that measures the carbon lost from the soil system and tree roots. For one of the newest projects at the crane, a Stanford University group monitors fine tree roots using 64 mini-rhizotrons. These yard-long tube!
s with video cameras and fiber optic cables can take pictures of roots so scientists can learn the longevity of individual roots, determine how their biomass changes and, eventually, relate such information to carbon uptake.
Jeff Klopatek, Arizona State University, 480-965-4685
Harold Mooney, Stanford University, 650-723-1179
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Surrounding forest — Forests of different ages near the crane site provide research areas for comparison and contrast. Measurements made at the canopy crane site, in adjacent managed forest stands and across the region are being correlated to data about forest types that can be gathered by satellites. Scientists are hoping to be able to scale up from trees in individual forests to entire landscapes and regions in order to estimate the results of widespread changes in forests.
Susan Ustin, Western region of Dept. of Energy’s National Institute for
Global Environmental Change, based at UC Davis, 530-752-7300
Other possible contact: Dar Roberts, UC Santa Barbara
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Surrounding forest — The first-ever, large-scale replicated experiment on the effects of timber harvesting in west-side Douglas fir forests is underway in the Wind River area. Called DEMO (Demonstration of Management Options) study, this long-term experiment compares how plants and animals, productivity and hydrology are affected when lands are harvested in different ways. The DEMO study is being done with three levels of permanent forest retention at harvest (15, 40 and 75 percent retention) and two patterns of retention (dispersed and aggregated).
Jerry Franklin, University of Washington, 206-543-2138
Other possible contact: Charlie Halpern, University of Washington
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NOTE:
The crane and forest around it are closed to the general public because of safety concerns (the forest around the crane, for example, is a hard-hat area), there are scientific instruments on the forest floor and the area needs to be kept as pristine as possible for research to be meaningful. Please don’t include the crane in travel or outdoors stories leading readers or viewers to think they can visit. This will only frustrate people and cause them to be upset with the research staff.
For inquiries about media visits to crane, contact: Sandra Hines, 206-543-2580, shines@u.washington.edu
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