Category: Forest health

Climate change may be factor in spread of tree fungus

Signs of hope? A single Douglas-fir grows at the base of the clearcut area along Swan Mountain Road. It'll be interesting to watch the area during the next few years to see how it regenerates.
Global warming may be promoting growth of a tree-damaging fungus in the Pacific Northwest. @bberwyn photo.

Commercially valuable tree stands take hit in Pacific Northwest

Staff Report

Global warming may be a factor in the spread of a fungus affecting valuable Douglas fir forests in the Pacific Northwest. Needle cast disease has recently spread across 590,000 acres in Oregon,  quadrupling since the start of surveys in 1996. The annual economic loss has been estimated at $128 million.

“The correlation between disease severity and climate factors, such as spring moisture and warm winter temperatures, raises the question of a link between disease expansion and climate change,” said  researcher Gabriela Ritokova. “Those factors, in combination with lots of Douglas fir and with large springtime fungal spore production, have us where we are now.” Continue reading “Climate change may be factor in spread of tree fungus”

Forests may not benefit from rising CO2 levels

Intense aspen and scrub oak color in this aerial view of Eagle County, Colorado.
Aspen and scrub oak forests in western Colorado. @bberwyn photo.

Study says disastrous tipping points could be reached by 2050

Staff Report

Forests of the future may not be able to remove heat-trapping CO2 from the atmosphere as effectively as previously thought, scientists said in a new study that’s based on an extensive analysis of tree ring data from the past.

“We utilized a network of more than two million tree-ring observations spanning North America. Tree-rings provide a record into how trees that grow in different climates respond to changes in temperature and rainfall,” said Brian Enquist, a professor in the UA’s Department of Ecology and Evolutionary Biology and a fellow of the Aspen Center for Environmental Studies in Aspen, Colorado.

The research challenges assumptions about how forests will respond to warmer average temperatures, increased greenhouse gas emissions, and shifting rainfall patterns. It also suggests that the warming climate already is rapidly pushing many forests towards an ecological tipping point, which may be reached as early as 2050, Exposure to unprecedented temperatures hampers tree growth and makes them susceptible to other stress factors. Continue reading “Forests may not benefit from rising CO2 levels”

California tree deaths part of global wave of forest mortality

Climate change is wiping out forests on a staggering scale

forests dying because of global warming
Red and dead lodgepole pines in Colorado. @bberwyn photo.
A beetle-killed lodgepole pine branch in Summit County, Colorado.
A beetle-killed lodgepole pine branch in Summit County, Colorado. @bberwyn photo.

Staff Report

California’s multiyear drought killed even more trees than previously thought, the U.S. Forest Service announced this week. Aerial and ground surveys show that 26 million trees across six counties in Southern California died, in addition to the 40 million trees that died statewide from 2010 to October 2015. Four years of drought, high temperatures and an outbreak of tree-killing bark beetles all contributed the historic levels of tree die-off, the agency said.

The tree mortality in California is the latest crest in a wave of forest die-offs in the past few decades linked with global warming. In the Southwest, an outbreak of ips beetles after the 2002 drought killed 80 percent of the piñon pine forests in the Four Corners region.

Around the same time, pine beetles started spreading across northern Colorado, parts of Wyoming and North Dakota, ultimately killing millions of acres of forest. And just as the pine beetle infestation waned, a spruce beetle outbreak in southern Colorado started to spread. Since 1996, spruce beetles have killed trees across about 1.5 million acres of forest.

Huge swaths of Colorado aspen forests also died in the early 2000s in a mortality event linked with extreme heat, and forest researchers say hardwood forests in the northern U.S. are also at risk from global warming. Continue reading “California tree deaths part of global wave of forest mortality”

Environment: Can prescribed fires make forests more resilient?

New study focuses on drought-stricken California forests

Beetle-killed forests now dominate the landscape in Summit County. Prescribed fires are needed to help regenerate forests and clear dangerous fuels, according to White River NF supervisor Scott Fitzwilliams.
Prescribed fires could help make forests more tolerant to drought and more resilient in a warmer climate. @bberwyn photo.

Staff Report

A rising tide of insect infestations, tree mortality and wildfires — all caused by global warming — has resulted in political pressure for more logging in U.S. Forests, but there’s plenty of research showing that cutting down trees doesn’t do much good and can even increase the fire danger.

Exploring alternative options for strengthening forest resiliency, researchers with the U.S. Geological Survey and the National Park Service recently found that thinning forests with prescribed fires can reduce drought. Continue reading “Environment: Can prescribed fires make forests more resilient?”

Satellite images map forest-fungi relationships

forest fungi
A new study helps map the relationships between forests and fungi on a large scale. @bberwyn photo.

New analysis offers important forest health information

Staff Report

Colorful mushrooms that pop up in forests around the world are much more than decorative baubles. Much more than realized, fungi are key components of forest ecosystems, helping to regulate the carbon cycle and driving the nutrient exchange between soil and trees.

One recent study showed the the recent bark beetle epidemic across the western U.S. may have wiped out crucial fungi that are critical to forest regrowth, and other research shows they helped stabilize global climate during low-C02 eras. Continue reading “Satellite images map forest-fungi relationships”

Morning photo: Countryside …

Spring landscapes

The Lower Austrian landscape encompasses everything from wild beech forests and deep river canyons to manicured fields — not to mention acres and acres of vineyard, but that’s another story! Austrians are still getting used to the concept of national parks. Thayatal was founded in 2002, so some local visitors still don’t quite understand why the park managers simply leave downed trees on the ground. It’s considered a waste by some, and the park features signs explaining how it’s a deliberate effort to recreate landscapes where natural processes are left to function without much interference. In this small country, nearly every acre of land is spoken for, most of it outside towns and cities dedicated to agriculture, but slowly, resource managers are making some headway in restoring natural ecosystems in a few areas, to the benefit of native species.

Aerial forest surveys track continued spread of spruce beetles across Colorado forests

State, federal scientists track forest health

Aerial survey results show how spruce beetles are taking a toll across Colorado’s forests, with new areas of infestation in the Sange de Cristo, the West Elks and even the northern mountains.
Spruce beetle populations are surging in the southern Rocky Mountains. bberwyn photo.
Spruce beetles are still spreading in the southern Rocky Mountains. @bberwyn photo.

By Bob Berwyn

The latest results from aerial surveys of Colorado forests shows that spruce beetles are doing the most damage, with infestations detected on 409,000 acres across the state, expanding onto 182,000 acres of previously unaffected forests. Since 1996, spruce beetle outbreaks have caused varying degrees of tree mortality on more than 1.5 million acres in Colorado.

The mapping shows spruce beetles spreading outward from the San Juans to the West Elk Mountains, the Sangre de Cristo Mountains and into the northern part of the state around Rocky Mountain National Park. See the full report here:

State forest experts said it was the fourth year in a row that spruce beetle outbreaks caused widespread tree mortality. As populations of spruce beetles expand, they are starting to affect higher-elevation stands of Engelmann spruce. The report says blowdown events, combined with long-term drought stress, warmer temperatures and extensive amounts of older, dense spruce, have all contributed to the ongoing spruce beetle outbreak. Continue reading “Aerial forest surveys track continued spread of spruce beetles across Colorado forests”