Logging no panacea for pine beetle outbreaks

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Can we log our way to forest health?

Science sometimes missing from forest management policies

By Bob Berwyn

FRISCO — While politicians and policy makers continue to conflate a number of complex forest health and wildfire issues, a new study suggests there’s little evidence supporting the idea that logging helps to control or contain the spread of tree-killing pine beetles.

Nobody disputes the need to clear trees, brush and other fuels from around homes in fire-prone forest areas, but some lawmakers who should know better have been pushing for more logging under the guise of restoring forest health and as an antidote to insect infestations.

The idea that speedy approval of logging projects could help restore forest health was also used as a basis for short-cutting environmental reviews for logging projects, possibly resulting in negative long-term environmental impacts in forests.

But forest researchers in California and Montana said there isn’t much monitoring to assess the effectiveness of logging, and that failures often aren’t reported, probably because they don’t fit the popular narrative. Continue reading

Good news, bad news for Colorado forests

Pine beetle infestation slows, but spruce beetles continue to spread

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Healthy spruce-fir forest at Vail Pass. bberwyn photo.

By Summit Voice

FRISCO — There’s good news and bad news for Colorado forests, according to state and federal officials, who said last week that the mountain pine beetle epidemic slowed dramatically in 2013, while spruce beetles continued to spread.

Statewide, mountain pine beetles were active on 97,000 acres in 2013, the lowest acreage of active infestation in 15 years. Since 1996, mountain pine beetles have killed trees across 3.4 million acres.

Spruce beetle were active on 398,000 acres, expanding by 216,000 new acres in 2013, compared to 183,000 new acres in 2012. The total area affected by this beetle since 1996 has reached more than 1.1 million acres. Continue reading

Forests: Canadian scientists decode pine beetle genome

Mountain Pine Beetle. Photo by: Ward Strong, B.C. Ministry of Forests, Lands, and Natural Resource Operations

Mountain Pine Beetle. Photo courtesy Ward Strong, B.C. Ministry of Forests, Lands, and Natural Resource Operations.

Findings may help forest managers control outbreaks

By Summit Voice

SUMMIT COUNTY — Scientists who recently completed decoding the pine beetle genome say their findings could help forest managers develop ways to manage the epidemic in the future.

“We know a lot about what the beetles do,” said Christopher Keeling, a research associate at Canada’s Michael Smith Laboratories. “But without the genome, we don’t know exactly how they do it.” Continue reading

Colorado foresters say no need to spray for pine beetles

Local company continue to offer spraying services, saying some property owners would rather be safe than sorry

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Pine beetle populations have dropped to the lowest level in 30 years in parts of the Colorado high country. Bob Berwyn photo.

By Bob Berwyn

SUMMIT COUNTY — While some local property owners report that they’re getting advertisements from local tree spraying companies about protecting lodgepole pines from mountain pine beetles, state officials say there’s no need to apply pesticides this year.

“Mountain pine beetle numbers are the lowest they’ve been in 30 years,” said Ron Cousineau, district state forester for the area covering Summit and Grand counties. “The mountain pine beetle population has crashed … spraying has to be based on an actual threat,” he said. “The current population of pine beetles does not warrant spraying.”

Essentially, the bugs have killed most of the available trees. With very few brood trees remaining, beetle populations aren’t likely to reach epidemic levels again anytime soon. The latest forest surveys showed pine beetle activity on only about 200 acres in Summit County last year, with only a few pockets of trees within those areas affected by the beetles. Continue reading

Study: Colorado forests not doomed

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New dawn for Colorado’s beetle-killed forests.

Intensive research shows vigorous regrowth in beetle-killed tracts

By Bob Berwyn

SUMMIT COUNTY — After years of uncertainty over the future of Colorado’s forest landscapes, a new study by U.S. Forest Service scientists puts the recent pine epidemic into perspective.

The insect outbreak ultimately will result in more diverse and resilient forests in the long run, adding structural complexity and species diversity, researchers with the USFS Rocky Mountain Research Station concluded after carefully monitoring regrowth in beetle-killed stands.

New growth is surging under the dying lodgepole canopy with the vertical growth rate of lodgepole and fir doubling in beetle-killed areas that were left untreated after the epidemic. Harvested stands also showed strong lodgepole regrowth, with aspen gaining ground in some places.

“Forests come and go … It’s not a crisis, but this was an amazing synchronism,” Forest Service biogeochemist Chuck Rhoades said of the massive pine beetle outbreak that will alter the forest landscape of the Southern Rockies for generations to come.

The bugs swarmed across vast swaths of the Canadian Rockies; they’ve invaded the Front Range and moved east to the Dakotas, especially the forests of the Black Hills.

“This event is not over, but the fear part should be over,” said Rhoades, who, with a team of researchers from the Fort Collins-based Forest Service Rocky Mountain Research Station, has been carefully studying regeneration in beetle-killed areas. “But the idea of forest health and maintaining forest ecosystem processes is something we’ll always be thinking about,” he said. Continue reading

Colorado: Pine beetle epidemic wanes

Spruce beetle infestation grows in southwestern mountains

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Aerial surveys show that spruce beetles are spreading in SW Colorado, while pine beetles slow their attack in the northern and central part of the state.

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The spread of mountain pine beetles slowed to levels last seen in 2003.

By Summit Voice

SUMMIT COUNTY — Mountain pine beetle activity in Colorado dropped dramatically in 2012, to the lowest level in 10 years, according to state and federal officials who this week released the the results of their latest aerial surveys.

Mountain pine beetles are still spreading across parts of the mountains between Estes Park and Leadville, but new activity was reported on just 31,000 acres, down from 141,000 acres in 2011. Since the outbreak started in 1996, beetles killed trees across more than 3.4 million acres, but it’s important to remember that not every single tree died.

In the aftermath of the infestation, foresters are finding that pockets of younger trees survived the wave of beetles, even in the hardest-hit areas. Continue reading

Pointing the way to pine beetle control, but at what cost?

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Pine beetle-killed trees in Summit County, Colorado.

Dartmouth scientists study pine beetle population dynamics

By Summit Voice

SUMMIT COUNTY — Dartmouth scientists say they may have found a pathway to keeping pine beetles in check, showing that their populations fluctuate between extremes, with no middle ground.

“That is different from most species, such as deer, warblers and swallowtail butterflies, whose populations tend to be regular around some average abundance based on food, weather, and other external factors,” said Matt Ayres, a professor in the Department of Biological Sciences at Dartmouth and senior author on the paper. “They don’t appear and disappear in cycles. Rather, they exist in two stable equilibrium states—one of high abundance and the other of scarcity.”

Once the population pendulum swings toward the high end, it won’t quickly or easily swing back, Ayres explained.

According to the new study, forest managers might be able to keep pine beetle populations at the low end of the scale by boosting competitor and predator beetle populations — but they don’t address how that could affect the overall equilibrium of forest ecosystems, especially those where older trees need a change agent like bark beetles to spur regeneration. Continue reading

Colorado: Study shows pine beetle invasion hasn’t led to serious nitrogen pollution in forest watersheds

Nature mitigates its own impacts

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Young trees and brush are increasing their nitrogen uptake in the wake of the pine beetle infestation, helping to minimize impacts to water quality. Bob Berwyn photo.

By Summit Voice

SUMMIT COUNTY — Early fears that the bark beetle epidemic could degrade water quality are proving unfounded, according to CU-Boulder scientists, who said smaller trees and undergrowth that survive the epidemic have increased their uptake of nitrogen as the older trees die.

While logging or damaging storms can drive stream nitrate concentrations up by 400 percent for multiple years, the team found no significant increase in the nitrate concentrations following extensive pine beetle tree mortality in a number of Colorado study areas, according to CU-Boulder Professor William Lewis. Continue reading

Forests: CU study traces evolution of pine beetle outbreak

Beetle-killed lodgepole pines dominate the landscape in many parts of Summit County.

2002 drought played key role in accelerating insect invasion

By Summit Voice

SUMMIT COUNTY — Drought conditions in the early 2000s helped pine beetle populations surge to unprecedented levels, according to a new University of Colorado study that charts the evolution of the current pine beetle epidemic in the southern Rocky Mountains.

But even when the drought eased, the outbreak continued to gain ground, spreading into wetter and higher elevations and into less susceptible tree stands — those with smaller diameter lodgepoles sharing space with other tree species, according to CU-Boulder doctoral student Teresa Chapman.

“In recent years some researchers have thought the pine beetle outbreak in the southern Rocky Mountains might have started in one place and spread from there,” said Chapman. “What we found was that the mountain pine beetle outbreak originated in many locations. The idea that the outbreak spread from multiple places, then coalesced and continued spreading, really highlights the importance of the broad-scale drivers of the pine beetle epidemic like climate and drought.” Continue reading

Climate trends to trigger massive change in SW forests

A thermal emission sensor on NASA’s Terra satellite acquired this view of the Waldo Canyon, Colorado burn scar. 2012,  Vegetation-covered land is red in the false-color image, which includes both visible and infrared light. Patches of unburned forest are bright red, in contrast with areas where flecks of light brown indicate some burning. The darkest brown areas are the most severely burned.

Current conditions already reaching historic megadrought levels with widespread tree deaths expected in coming decades

By Summit Voice

FRISCO — Forests of the southwestern U.S. may be on the verge of dramatic changes in the coming decades, as a warming climate may squeeze many species of their narrow ecological niche.

New research shows that Southwest drought conditions in recent years are as intense as they were during the historic megadroughts of the 1200s and 1500s.

Southwestern forests grow best when total winter precipitation is high combined with a summer and fall that aren’t too hot and dry, but many climate models suggest the region will be warmer and drier. New Mexico just experienced its driest 24-month stretch on record.

If those conditions persist, it would likely result in widespread tree deaths and significant changes in the distribution of species on a regional landscape level, according to a new report published in the journal Nature Climate Change last week.

To measure the impacts of climate change, the scientists developed a stress index, factoring winter precipitation, late summer and fall temperatures, and late summer and fall precipitation into one number. Continue reading

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