by Seth Truscott
Washington State University scientists seek help from residents of the Pacific Northwest in tracing the worrying die-off of an iconic forest tree, the western redcedar.
A distinctive, useful, and beautiful giant, the western redcedar has historically provided Native American tribes with much of the materials for practical objects and culture. Valued for its natural beauty and soft, red timber, which resists decay and repels insects, redcedars can reach nearly 200 feet in height and live for more than a thousand years.
Western redcedars are found throughout the Northwest due to their tolerance for shade, flooding, and poor soils, thriving where other trees cannot.
Over the last few years, however, scientists have observed an increasing number of dead and dying trees. Mortality begins with dieback, in which the tops and branches die from the tips. Some specimens survive, but the condition can also kill.
Joseph Hulbert, postdoctoral fellow in WSU’s Department of Plant Pathology, founded the Forest Health Watch program to enlist citizen scientists in understanding and preventing dieback.
Researchers believe the problem is spurred by longer, hotter droughts in the region. But it’s unclear if precipitation, temperature, consecutive dry days, or other environmental factors are the main factor.
Launched in 2020, Forest Health Watch seeks answers. Citizens help by logging and photographing sites where trees are healthy, dead or dying back. People can also identify sites and conditions where trees may be vulnerable, and watch for signs of disease or pests.
“Anyone can be a community scientist,” Hulbert said. “All you really need is a camera for this project.”
Hulbert launched the Western Redcedar Dieback Map on the iNaturalist citizen science website to allow citizens to easily log their sightings.
“Once we have a strong understanding of the areas where trees are vulnerable, we can begin to explore options for keeping trees healthy in those areas,” he said.
Things are looking up in a swath of forest in southern Germany, thanks to innovative funding from the European Union for a project that aims to help policymakers better understand how the forest’s ecosystems work.
The ECOPOTENTIAL project uses satellite images for ecosystem modelling in 25 Protected Areas in Europe (as well as Kenya, the Caribbean and Israel) to address climate change and other threats to ecosystems. In the Bavarian forest, the images and mathematical models of ecosystems, or “Earth Observation tools”, are helping to assess the impact of climate change and pollution, and shape national protection policies.
UN Environment is one of many partners supporting the 2015-2019 ECOPOTENTIAL project, funded by the European Union to the tune of 16 million euros.
Within the ECOPOTENTIAL project, Earth Observation tools and “remote sensing”, including by aircraft and drones, are being used to better understand how vegetation is evolving across the park and over time.
Satellite and drone pictures are detecting patterns of dominant plant species, linking habitat characteristics with terrain, and tracking animal movements. The park administration is also carrying out intensive research on tree regeneration, the role of dead wood, and the impact of global warming and extreme climatic events on the future development of these ecosystems.
By Scott Miller
New insights into the impact forests have on surface temperature will provide a valuable tool in efforts to mitigate climate change, according to a new research paper co-authored by Clemson University scientist Thomas O’Halloran.
For the first time, scientists have created a global map measuring the cooling effect forests have by regulating the exchange of water and energy between the Earth’s surface and the atmosphere. In many locations, this cooling effect works in concert with forests’ absorption of carbon dioxide. By coupling information from satellites with local data from sensors mounted to research towers extending high above tree canopies, O’Halloran and his collaborators throughout the world have given a much more complete, diagnostic view of the roles forests play in regulating climate.
Their findings have important implications for how and where different types of land cover can be used to mitigate climate change with forest protection programs and data-driven land-use policies. Results of their study were recently published in the journal Nature Climate Change.