Tag: beetles

An ecologist working for the U.S. Forest Service says pine needles killed by a mountain pine beetle infestation ignite faster than green needles. Here is an excerpt from the Missoulian:

HELENA – The red needles of a tree killed in a mountain pine beetle attack can ignite up to three times faster than the green needles of a healthy tree, new research into the pine beetle epidemic has found.

The findings by U.S. Forest Service ecologist Matt Jolly are being used by fellow ecologist Russ Parsons to develop a new model that will eventually aid firefighters who battle blazes in the tens of millions of acres from Canada to Colorado where forest canopies have turned from green to red from the beetle outbreak.

The new model incorporates a level of detail and physics that doesn’t exist in current models, and it is much more advanced in predicting how a wildfire in a beetle-ravaged region will behave, Parsons said.

“It gives you so much more information about what to expect,” he said. “Are these people safe here or should they run away? If we put a crew on the ground here, can they make it to the top of the ridge in ample time?”

Many communities in the Rocky Mountain West have beetle kill forests in some proximity.

And the new research dispels the notion that beetle-killed trees present no greater fire danger than live ones, a theory that had gained traction after a couple of wet, cool summers tamped down fire activity in the region, Jolly said.

On the contrary, beetle-killed trees can hold 10 times less moisture than live trees, Jolly found. That means they not only ignite more quickly than live trees, but they burn more intensely and carry embers farther than live trees, Jolly said.

He found that it takes less heat for wildfires to spread from the ground to the crowns of beetle-killed trees, making a wildfire in a forest with beetle-killed trees potentially much more difficult to contain.

Mountain pine beetles also start losing their moisture before the needles change to that tell-tale red, Jolly said, meaning even a healthy-looking pine tree could pose an increased fire threat to an unsuspecting firefighter.

Jolly took more than 1,000 tree moisture content measurements and conducted hundreds of ignition tests last year in four states, using foliage from trees with red, yellow, orange and green needles.

Jolly and Parsons will present their research Wednesday in Helena at a seminar on wildfires and the mountain pine beetle held by the Montana Department of Natural Resources and Conservation. The seminar will also host researchers from the University of Idaho and British Columbia, where the beetle infestation covers an estimated 43 million acres, which is more than 67,000 square miles.

So far this is information presented by a reporter. It will be interesting to read the actual findings of Mr. Jolly’s study. The article does not say what species of trees was involved in the study nor does it describe the ignition tests.

Research on lodgepole pines in the Greater Yellowstone area has yielded this information:

Modeling results suggested that undisturbed, red, and gray-stage stands were unlikely to exhibit transition of surface fires to tree crowns (torching), and that the likelihood of sustaining an active crown fire (crowning) decreased from undisturbed to gray-stage stands. Simulated fire behavior was little affected by beetle disturbance when wind speed was either below 40 km/h or above 60 km/h, but at intermediate wind speeds, probability of crowning in red- and gray-stage stands was lower than in undisturbed stands, and old post-outbreak stands were predicted to have passive crown fires. Results were consistent across a range of fuel moisture scenarios. Our results suggest that mountain pine beetle outbreaks in Greater Yellowstone may reduce the probability of active crown fire in the short term by thinning lodgepole pine canopies.

Wildfire Today has written frequently about the effects of pine beetles on wildfire.

More information about the May 4, 2011 forum “Mountain Pine Beetle and Fire which will be broadcast live on the internet.

Thanks Dick

The following press release was distributed by the Montana Department of Natural Resources and Conservation.

PRESS RELEASE

MOUNTAIN PINE BEETLE & FIRE: THE SCIENCE BEHIND THE RISKS

Helena seminar on May 4th brings in local and national experts

Missoula, MT, April 11, 2011: Much has been debated about the after-effects of Montana’s mountain pine beetle outbreak. Perhaps the largest area of debate centers on wildland fire risk during beetle attack, in the “red needle phase” the “gray phase,” and the “down phase.” Does the mountain pine beetle outbreak correlate to increase wildland fire risk? What type of fire behavior has been observed in the forest post outbreak? What are the long term implications related to fuel loading and future fire behavior?

The Mountain Pine Beetle Forum is hosting the seminar, “Mountain Pine Beetle & Fire: The Science Behind the Risks”, with experts from the scientific and local community whose research and experiences will provide insight on these topics. It will be held at the Red Lion Colonial Inn in Helena on May 4, 2011, with two opportunities to attend: a day-long session with longer, more technical presentations, and a general evening presentation from 6:00pm-9:00pm with the same presenters, but in a more concise, less technical format.

“Everyone is welcome to attend either or both sessions,” said Paula Short, spokesperson for the Montana DNRC who is one of the hosts for the event. “Our desire in providing two sessions was to make it available to both resource professionals and those who could come and spend the day as well as for the volunteer firefighter or private landowner who could only attend after regular business hours.” The event will also be broadcast on the internet, enabling participation by anyone who is unable to travel to Helena.

Presenters include researchers from the University of Idaho, the Missoula Fire Lab, British Columbia Forest Service, and local experts from the U.S. Forest Service, DNRC and the private sector. Complete details can be found at the Mountain Pine Beetle Forum website: http://www.beetles.mt.gov. There is no cost to attend, but an RSVP is requested and can be made by calling the DNRC Forestry Division in Missoula at (406) 542-4300.

This event is sponsored by the interagency Mountain Pine Beetle Forum, the USDA Forest Service Western Wildland Environmental Threat Assessment Center and the Tri-County FireSafe Working Group.

The event will be broadcast live on the Internet.

Firefighter burned in Oklahoma

A firefighter working on a grass fire in Rogers County, Oklahoma was burned Saturday. A spokesman for the Tri District Fire Department in Claremore, OK (map) said the firefighter suffered second and third degree burns on his hands, but “is doing fine now”, according to Emergency Management Director Bob Anderson.

Firefighters in Rogers County were very busy on Saturday as strong winds pushed numerous grass fires through fuels that had been “freeze-dried” by snow over a week ago. One of the fires started when a bush hog hit a rock that sparked, and another fire burned over 2,000 acres.

The fire on which the firefighter got burned was started by a resident burning brush. That fire endangered 15 houses, and “probably the only thing that saved them was they were brick”, said Anderson.

Black Hills pine beetle epidemic compared to 10,000-acre fire

On Monday newly elected U.S. Representative Kristi Noem held a roundtable meeting at the Black Hills National Forest Mystic Ranger District office in Rapid City, South Dakota (map). One of the primary topics was the impact of the mountain pine beetle on the forests and the economy. Tom Troxel, director of the Black Hills Forest Resource Association, compared the beetles to a large wildfire:

If there was a 10,000-acre fire in the Black Hills, the Forest Service would have all the people and money they needed. And I think this pine beetle epidemic is every bit as catastrophic as a 10,000-acre fire.

Rapid City Mayor, Alan Hanks said big fires chase tourists away and damage the economy. And the Black Hills is just one big fire away from the kind of economic and social impacts those who care about the area hate to imagine, he said. He advocated increased timber harvesting in order to slow the spread of the beetles.

Noem said she would work on making the administrative process to thin the forests less cumbersome, and would seek to eliminate “job-killing regulations”. She reminded those attending the meeting that her membership on the House Natural Resources Committee and its Subcommittee on National Parks, Forests and Public Lands will provide opportunities to streamline regulations on forest management.

Much as been written about the impacts of mountain pine beetles on forests and how beetle-killed trees would affect wildfire management. Wildfire Today has covered this before.

The Times News of Twin Falls, Idaho, has an interesting article about the beetle outbreak. Here is an excerpt:

“…Overall in this area, (the mountain pine beetles have) been outbreaking since around 2000, going on 11 years,” said Laura Lazarus, a forest entomologist with the Forest Service’s Forest Health Protection office in Boise. The mountain pine outbreaks typically subside in an average of 12 years.

Lazarus acknowledged that the visual impact of the beetle kill — the hillsides full of dead, red-needled trees — looks bad to the untrained eye. However, because the beetles only target trees of a certain size, there are plenty remaining to repopulate the forest over time.

“It’s very shocking right now, but it’ll be fine in the long-term,” she said. “Really, we’re just left with younger stands of trees. Generally, those trees will grow more vigorously. I don’t always see it as a bad thing.”

However, Lazarus, [Kurt Nelson, district ranger at the Forest Service’s Ketchum ranger district] and their colleagues are paying close attention to where the beetles are active, in part to know where dead needles and fallen trees are adding to the fuel load for a potential wildfire.

“It does change our fire regimes in terms of how often and how large a fire could occur if the right conditions occur,” Nelson said. “It’s all connected and we need to recognize there are some things we may not be able to control but we can manage in terms of what we might anticipate.”

Joe Lowe, the Wildland Fire Coordinator for the State of South Dakota has written an opinion article for the Rapid City Journal about the relationship between pine beetle outbreaks and fire. Here are some excerpts:

In recent days, there has been much discussion about bark beetles and fire. With over 400,000 acres of our Black Hills attacked by pine beetles, the issue must be aggressively addressed.

[…]

The pine beetle attacks present three different and unique set of fire problems depending on when the attacks occurred.

The first phase is in the early stages of the beetle attack. The trees are dying or dead with the needles still on them and the crowns are close together.

Under the tree canopy we have ladder fuels that allow the surface fire to step up into the dead trees. This is called a crown fire. In this example I would expect to see a rapidly spreading fire of great intensity to occur.

The fire does not have to drive off moisture in the trees to sustain combustion. Every firefighter understands these basic fire principles.

In the second phase the needles have fallen off and the tree trunk and branches are still standing. In this phase the fire would mainly be a surface fire with opportunities to suppress it.

During the third phase the trees start to fall and create timber litter on the forest floor.

The heavy fuels are now horizontally distributed, and will contribute to higher intensity surface fires.

Make no mistake about it. In my opinion, a fire problem does exist in the Black Hills Ponderosa forest that has been attacked by pine beetles.

In the article, Chief Lowe makes some very good points. He also mentions research being done on the relationships between fire and beetle outbreaks in lodgepole pine and Douglas fir forests which we covered on September 8, 2010. One research project, funded by the Joint Fire Science Program, is being conducted by William Romme and Philip Townsend in the greater Yellowstone ecosystem. Other related research is being done by Monica Turner and Martin Simard.

One of the key facts from the research that has come to light so far is that the very flammable volatile oils which fuel a fire in green pine needles begin to break down when the needles die, making them less likely to sustain a fire according to the researchers. Previously, this has not been widely recognized by firefighters and may seem counter-intuitive.

Research needs to specifically determine how the reduced volatile oil content in dead needles may or may not counter-balance the lower moisture content in the dead needles. Which fuels a fire more, the oils, or a lower fuel moisture? If it is the oils, as the research at this point leads us to believe, then beetle-killed trees with dead needles would be less of a fire problem than green trees. That is, the rate of spread, likelihood of a crown fire, and the resistance to control would be reduced.

And there is little argument among wildland fire professionals that dead standing pines without needles are less likely to sustain a crown fire than green trees. After the dead trees fall, a ground fire would produce a great deal of heat, but I believe the rate of spread and resistance to control would be much less than a fire in standing green trees.

As Chief Lowe correctly points out, other factors may also be considered when decisions are made about a beetle outbreak, including the monetary value of commercial timber, and the aesthetics of dead trees compared to a green forest in an area visited by tourists. The safety of firefighters and hikers can also be an issue as the trees fall. Fighting fire in a snag forest may not be feasible.

As you hear so often, more research is needed, especially in Ponderosa pine forests.

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UPDATE January 29, 2010

A paper has been recently published, titled “Do mountain pine beetle outbreaks change the probability of active crown fire in lodgepole pine forests?” Here is an excerpt from the abstract:

Modeling results suggested that undisturbed, red, and gray-stage stands were unlikely to exhibit transition of surface fires to tree crowns (torching), and that the likelihood of sustaining an active crown fire (crowning) decreased from undisturbed to gray-stage stands. Simulated fire behavior was little affected by beetle disturbance when wind speed was either below 40 km/h or above 60 km/h, but at intermediate wind speeds, probability of crowning in red- and gray-stage stands was lower than in undisturbed stands, and old post-outbreak stands were predicted to have passive crown fires. Results were consistent across a range of fuel moisture scenarios. Our results suggest that mountain pine beetle outbreaks in Greater Yellowstone may reduce the probability of active crown fire in the short term by thinning lodgepole pine canopies.

The paper is written by Martin Simard, William H. Romme, Jacob M. Griffin, and Monica G. Turner.