Have some plants evolved to promote fire?

Olivia Judson, an evolutionary biologist, recently traveled to Australia where she learned a little about fires in eucalyptus forests. In an article she wrote for the New York Times, she wonders if some plants have specific characteristics that make it more likely that fires will burn intensely. Here is an excerpt from her article.

….It’s common knowledge that plants regularly exposed to fire tend to have features that help them cope with it — such as thick bark, or seeds that only grow after being exposed to intense heat or smoke. But what is less often remarked on is that the plants themselves affect the nature and severity of fire.

For example, dead branches burn more readily than living branches, so a tree that keeps dead branches (rather than letting them fall) makes it easier for a fire to climb into a forest canopy: the dead branches provide a ladder for the fire. Deadwood also allows fires to get hotter. Leaves that are high in cellulose, or that contain oils, also stoke the flames. Resins and gums are highly flammable. And as any girl scout knows, twigs catch light more readily than branches, so a twiggy sort of plant can catch fire more readily than its non-twiggy sister.

But here’s the odd thing. Many plants that live in places prone to fire are highly flammable — more flammable than plants that live elsewhere. This has led some to speculate that these plants have actually evolved to cause fires: that they “want” fire, and have evolved features that make it more likely that a spark will become a flame, and a flame will become a fire. I call this the torch-me hypothesis.

The argument goes like this. Many plants depend on fire for their propagation. Indeed, without fire, these plants disappear. If, for example, longleaf pine forests do not burn regularly, the pines will be replaced by water oaks and other species. So — runs the argument — fires are desirable because they kill the competition. Plants that enhance fires may thus have an evolutionary advantage: they murder the competition while creating the right circumstances for their own seeds to sprout.

This idea has sparked a heated debate. The problem is, showing that a trait has evolved because it enhances fire is difficult. Yes, oily leaves are more flammable; but perhaps the real advantage of oily leaves is that insects don’t enjoy eating them. Then, their flammability may be a by-product of tasting terrible.

The best evidence that some plants may have evolved to promote fire comes from pines. Some species of pine keep their dead branches; others tend to self-prune. As you would expect under the torch-me hypothesis, the more flammable species — the ones with the dead wood — also tend to have seeds that are released by fire. In short, the two traits go together….

The author seems to think she is the first person to consider this concept.

Lodgepole pine, photo: N. C. Heywood

One example of this is the lodgepole pine. It has shaggy bark and does not self-prune its limbs readily, so a fire at the base of the tree can, under dry conditions, run up the trunk of the tree and become a crown fire. It has a fire return interval of about 300 years, and fires tend to be of the stand replacement type, leaving nothing but snags. The serotinous cones open and disperse the seeds after the fire, promoting the resurgence of another lodgepole forest.

Lodgepole pine infested with dwarf mistletoe. Photo: D. Johnson

UPDATE: Chuck Bushey wrote to us about this.

Bob Mutch actually wrote his MS thesis on this topic at the University of Montana in the late 70’s. It was later published in the Journal of Ecology and I think he was the first to formally express the concept in the scientific literature.

Chuck later said the actual citation is:

Mutch, Robert W., 1970. Wildland Fires and Ecosystems – A Hypothesis.

Ecology, Volume 51(6):1046-1051.

Changes in helicopter contracting and management

Tom Harbour, the Director of Fire and Aviation Management for the U.S. Forest Service, sent a memo dated yesterday to the Regional Foresters. It covers some changes that will be made in the contracting and management of helicopters used on fires.

Usually initiatives like this are the result of a specific incident or accident. The federal fire agencies are more likely to enhance safety after fatalities occur rather than being proactive to prevent them. Of course the memo does not identify what precipitated these changes, but one has to wonder if the accident on August 8 last year that involved the Type 1 helicopter and the deaths of 9 firefighters on a fire in northern California had anything to do with it. As far as we know those accident reports, USFS and NTSB, have not been made public.

Date: July 7, 2009

To: Regional Foresters

This memo is to inform you of the operational safety enhancements in the Aviation program for 2009. The key actions are in progress and listed below:

  • Multiple contract changes are being made to the national helicopter contracts.
    • Aircraft will be weighed with FS maintenance inspectors present to verify weight submitted with contract bid.
    • More stringent standards for seating and restraint systems.
    • Contract scope now contains active safety management requirements.
    • A copy of the performance charts submitted for bid will be onboard each helicopter to allow the helicopter manager to verify the correct performance charts are being used.
    • Increased number of vendor training pilots will be allowed to accompany less experienced pilots during incident operations to provide tactical training and increased oversight.
  • Contract compliance inspection teams will be dispatched during field operations.The Department of the Interior Aviation Management Directorate is a partner in this initiative and will enhance capability and the number of teams that can be deployed.
  • As helicopters are activated for early use, compliance teams will be dispatched to conduct spot inspections and weight verification.
  • Performance planning charts for all contract helicopters will be available via the web to allow helicopter managers to ensure the accuracy of load calculation allowable payloads.
  • Continue to utilize more Exclusive Use (EU) helicopters and minimize use of Call-When-Needed aircraft.EU helicopter managers are generally better trained and more experienced and provide safer and more efficient operations.
  • Independent contractors will be hired to develop an Operational Risk Management (ORM) risk/benefit analysis process.
  • A formal risk assessment of Type I helicopter passenger transport has been completed by a professional aviation safety consultant. Assessments of Type 2 and 3 operations are planned.
  • Formal program reviews for the seven national Type 2 helicopters will be completed this season.

Regional Foresters

These items are critical for the continued safety and success of our aviation program and are underway. If you have any questions please contact Karyn Wood, Assistant Director for Operations.

(signed by Tom Harbour)

A Smokejumper’s tragic jump

KGW.com [link no longer works] has an article about a smokejumper that you should read. Sara Brown, on her 88th jump, collided with another jumper while decending to a fire. Her chute collapsed, she fell from 100 feet, and shattered her right leg.

She has endured a lengthy recovery, but last week, she was honored with the Smokejumper Courage Award from the National Smokejumpers Association

Fires caused by fireworks, part 2

Yesterday we started a list of the fires that were caused by fireworks. Today we are adding to the list as more reports are available.

13. Padre Island, Texas: People with fireworks caused several fires on unoccupied islands in the Laguna Madre. No homes were threatened and the fire department had no boats, so the fires are being allowed to burn until they run out of fuel, which should happen sometime on Sunday.

14. Burbank, Wash.: A fire that may have been started by fireworks burned onto the grounds of a biodiesel plan early Saturday. About 30,000 gallons of vegetable oil spilled during the 3-alarm fire.

15. Canal Winchester, Ohio:Fireworks were the cause of a fire in the 5900 block of Waterloo Road that totally destroyed a barn, according to a report from the Fairfield County Sheriff’s Office.Victims said they lit the fireworks and put the remnants in a truck, which they parked in the barn. Between 11:30 p.m. Friday and midnight Saturday, the trash caught fire, consuming the vehicle and then the structure.

The report indicated the barn and items inside appeared to be a total loss.The fire caused an estimated $150,000 in damages.

16. Richland, Wash.: Fireworks are suspected as the cause of a 20-acre fire.

17. Greenwood, Miss.: Investigators believe fireworks were the cause of a fire that destroyed Perry’s Pawn Shot and a vacant building.

18. Tehachapi, Calif.: The City of Tehachapi’s annual 4th of July fireworks display ignited a small grass fire that lit up local airport runways and briefly delayed traffic at the intersection of Tehachapi Boulevard and Dennison Road.

Carin Enovijas photo

Within an hour, the grass fire was contained by local firefighters, with back up units responding from as far away as Mojave, Tehachapi’s Chief of Police Jeff Kermode said. The Tehachapi Police Explorers assisted with traffic control at the scene.

According to Kern County Fire Department’s Public Information Officer Sean Collins, county firefighters responded to 245 incidents within two hours of sundown.

19 & 20. Yakima, Wash.: Two homes were badly damaged by separate fires caused by fireworks.

21. Covington, Wash.: From Seattlepi.com:Four homes in Covington were damaged by fire Saturday evening when fireworks ignited juniper bushes near one of the homes, the city of Kent reported.

The incident occurred in the 25400 block of 163rd Avenue Southeast when flames leaped from the bushes to ignite the siding of a two-story house. The fire quickly spread to the attic and then into the home.

Firefighters arrived to fight the fire, but sparks spread to three nearby residences, igniting their shake roofs. The fires at two of those houses were put out quickly with only minimal damage to the roofs, but the third house was on an adjacent street and had time to spread before firefighters were notified of the problem.

Firefighters from Kent Fire Department and Maple Valley Fire and Life Safety responded. The warm weather forced firefighters to be rotated out of duty frequently to stay hydrated.

Covington police cited an individual for discharging the fireworks in a dangerous manner, although the fireworks which started the fire were “of the legal type,” according to a spokesman.

22, 23, & 24. Snohomish County, Wash: Three structures burned in separate incidents, all caused by fireworks.

25. Tampa, Florida: Fireworks launched from across the street set a house on fire Sunday afternoon causing about $50,000 in damage.

26. Honolulu, Hawaii: We’ll count this as one fire, but the Honolulu Fire Department responded to 45 fires over the last two days that appear to be fireworks related, a spokesman said in an e-mail this morning.From midnight Thursday to midnight last night, firefighters responded to 26 brush fires, said fire Capt. Terry Seelig. Of those, 19 appear to have been started by fireworks. There were also 28 fires in trash bins or involving rubbish. Fireworks may have started 23 of those fires.

27. Sacramento, Calif.: Investigators believe illegal fireworks may have caused a two-alarm fire that tore through the back of an Oak Park home Saturday night, a Sacramento Fire spokesman said.

Sacramento fire crews arrived to find heavy smoke and flames pouring out of the back of a home on the 3400 block of 12th Avenue around 10:18 p.m. Saturday, Sacramento Fire Capt. Jim Doucette said.

The blaze quickly went to two alarms as approximately 50 firefighters worked to keep the flames from spreading to the house next door. Crews were able to contain the blaze to the single home, which sustained extensive damage before firefighters could fully douse the flames.

15-year old boy arrested, may have set 18 fires

Police in north Idaho arrest boy after arson spree

From The Olympian:

COEUR D’ALENE, Idaho – A 15-year-old boy suspected of setting 18 fires in the last month has been arrested in northern Idaho.

Coeur d’Alene police say the boy is being investigated in connection with 15 recent wildland fires and then three more fires near Skyway Elementary School. The fires were quickly extinguished.

Coeur d’Alene Deputy Fire Chief Glenn Lauper said it was critical to make an arrest due to an increased chance of fires this weekend because of fireworks, low humidity, high temperatures and no expected rain.

“We’re going to be busy enough with other emergencies,” Lauper told the Coeur d’Alene Press. “Those extra fires were putting a drain on our resources.”

After eight fires were set in the last week, officials asked for the public’s help, which Lauper said was a difficult decision because it could have made it harder to catch whoever was setting the fires.

“We had to make a calculated risk analysis,” Lauper said. “Once we go public, we have to have the resources to put into that investigation because it could either shut him down or make him accelerate his activities.”

Coeur d’Alene police Sgt. Bill Tilson said tips from area resident’s led to the boy’s arrest late Thursday.

“The patrol division received some tips and we followed up on those tips,” he said. “Thanks go to the citizens of the city.”

Lauper said the boy, who is being held in a detention facility and whose name has not been released, has told officials details about the fires. He said the boy and his parents are cooperating with officials.

“He told us things that were absolutely consistent and confidential to the investigation,” Lauper said.


Watch Out Situation #18

On February 26 Wildfire Today posted some of the history of the “18 Watch Out Situations”. As we explained then, they began with the “13 Situations that Shout Watch Out” in the 1960s, and evolved in 1987 into the “18 Watch Out Situations”.

Each day between March 19 through March 30 (and on Feb. 26) we posted images depicting each of the original 13 Situations that were in the “Basic 32” wildland firefighter training program that was developed by the El Cariso Hot Shots 1972-1973.

The image above is the 13th and final one we have posted. It is similar to Situation #18 on the present day list of 18.

To see all of the “13 Watch Out Situation” images that have been posted to date, click on the “13/18 Situations” tag below.

To Use the Images

The 13 images we have posted here are rather low resolution, but feel free to use them. The black and white images were originally produced by the U.S. Government, and were colorized in 1972 by a member of the El Cariso Hot Shots.

They should work well in PowerPoint presentations or on web sites, but if you want to print them larger than 5″ x 7″, you will need higher resolution images, which I have. The higher resolution copies are 300 dots per inch (DPI) and each file is about 1.2 Mb. But if you need them go to our Documents page and download the zipped file with all 13 images; the file is about 14 Mb.