Fire Ecology

Babbitt calls for change in fire suppression policy

A prescribed wildland fire policy would yield rangelands and forests that are healthier, safer and more productive over the long term, said Interior Secretary Bruce Babbitt in a speech to the 20th Tall Timbers Fire Ecology Conference in Boise, Idaho. Babbitt, fresh from his experience out on the fire lines of Arizona, addressed the conference, which was attended by ranchers, loggers, conservationists and outdoor enthusiasts.

"Nine decades of strenuous fire suppression have reduced the natural diversity and vitality of our plants and wildlife," said Babbitt. In order to forge a consensus behind prescribed wildland fire, Babbitt called for the use of the Bureau of Land Management's newly created Resource Advisory Councils to build federal-state-private coalitions at the local level and to reinvest a larger share of the proceeds from public lands to maintain the health and productivity of those resources

Why should we as Babbit has stated... supress our fire suppression policy? First let's learn what natural fire-adapted ecosystems are all about, then discuss when and how this perspective should be applied.

II Types of fire:

I. Three general patterns of natural fire spread are recognized:

(1) ground fires, which burn organic matter in the soil beneath surface litter sometimes down to the bare rock are sustained by glowing combustion. They occur in areas with peat accumulation or buildup of conifer needles. Without flame, they burn intensely often causing the most destruction.

(2) surface fires, the most common type, spread with a flaming front and burn leaf litter, fallen branches and other fuels located at ground level. Although they can kill thin barked trees and most herbs, older trees with thicker bark are protected.

(3) crown fires, which burn through the top layer of foliage on a tree, known as the canopy or crown fires. Crown fires, the most intense type of fire and often the most difficult to control. Strong winds, steep slopes and a heavy fuel load are required for continued burning.They hop and skip causing a mosaic of burned and unburned areas.

Even though fire is a fairly common occurrence, very few fires become extremely large. In the United States, 2 to 3 percent of all fires account for more than 95 percent of the total area burned annually. The blackened plots left behind by these types of large fires contribute to the image of fire as a destroyer of the natural environment. In reality, the opposite is true

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	Photo of the Yellowstone Park fire, an example of a devasting fire due to buildup of high organic content which accumulated when earlier natural burns were prevented.

The role of prescribed or planned burnings according to the Forest Service and its supporters:

" Regular prescribed fires can reduce the amount of ground fuels, thereby lowering the likelihood of potentially large and uncontrollable wildfires. If future wildland fires should occur, the fires would be less intense and easier to control. Fuel reduction can help prevent the possibility of crown fires, which burn at high intensity and are capable of causing unacceptable change. However, in five to eight years enough litter can accumulate in a forest to return ground fuel quantity to the pre-fire level. Therefore, it is important that "a regular, planned burning program is followed rather than a single fire event".

Among the other benefits of prescribed burning are:

• * insect pest control;
• * removal of undesirable plants that compete with wanted species for nutrients;
• * addition of nutrients for trees and other vegetation provided by ashes that remain after a fire;
• * removal of undergrowth, thereby allowing sunlight to reach the forest floor to encourage growth of desirable species; and
• * clearing of congested forest areas to facilitate planting (?).

Data from the Forestry Service on natural and prescribed fires in the US this year:

1997 Wildfire / Prescribed Fire Statistics

Region

# of wildfires

acres burned

# of prescribed burns

acres of burn

Region 1	62	1345	49	12330
Region 2	90	12702	89	58400
Region 3	18	550	130	15435
Region 4	99	5437	268	87180
Region 5	33	202	97	4688
Region 6	51	855	104	13699
total 1-7	400	521,371	737	191,734

Thought Question ( possible exam question)

According to the above data, prescribed burnings are already a given policy. Is the public awareness of the importance of prescribed burning just a strategy by Forest Service to win over support of a policy they have already endorsed as they did previously with Smoky the Bear? Are they swinging too far in the opposite direction? Is natural burning another or better alternative or is prescribed burning necessary?

Forestry industry is countering that if you are burning, why don't you let us come in before and cut the trees down to reduce overcrowding and possible fires.Environmentalists object stating animals need the old growth intact, the will not cut down only the little stuff ( with little economic value) they damage the forest floor with their heavy equipment, they require the building of roads which thwarts animal migration and so on.

What is the solution? Before you decide, let's learn more about ecosystems which normally experience fire, as these are the ones which are most likely to be subjected to presctribed burning or to experience fire as a natural course.....

Energy source---litter sufficiently high and dry
Dry conditions--- generally due to drought- either part of the natural system's climate ( dry summer/wet winter)
Ignition source:lightning or arson or prescribed burning

In each of the following ecosystems, determine which factors contribute to the high energy source needed, what promotes the dry conditons and who is the likely candidate to set the fire.......

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IV. Ecosystems which are fire dependent or experience them enough to have evolved adaptations:

I have created a separate page for each; note some of the adaptations evolved by the major species to either maintain their community through initiation of fires or survive fires.

• Ponderosa pine regions 2, 6, 1
• Chaparral south region 1
• Long leaf pine region 4
• Tall grass prairies region 3
• Jack pine-hardwood forests -region 2
• Douglas fir forests - region1 north

2. Animal adaptations are few unlike plants. Wildlife species have developed different methods or strategies to escape fires. Animals such as deer, elk, bear and fox are accomplished runners and use this skill to escape the flames. Other animals less well adapted for running hide in underground burrows, in rock cliffs or other refuges.Rats, mice, moles, shrews, snakes, lizards and turtles burrow to escape fire.

Birds that have the ability to fly retreat to a safer area until the flames have passed. However, nestlings and chicks of wild turkeys and other birds may not be able to fly. Often these and other animals cannot escape the fire's path. Their remains attract scavengers and predators,such as coyote, to recently burnedor still burning areas to capture animals on the run. After a fire, populations of organisms that inhabit the litter or O layer often decrease. Some of the insects in the O-A layers are considered pests because they damage timber stands. Sawflies, the red pinecone beetle and the maple leaf cutter are examples of nuisances whose numbers are reduced by fires. While some invert populations decline as a result of fire, some insect including ants seem to prosper. Ant populations are more numerous in burned areas than in unburned areas. An important species in prairies, ant populations ( which are responsible for seed distribution, air exchange etc) increase after a prairie fire.

Generalized adaptations: 1. Basic motility- fast though not all make it 2. Burrowing habit: many rodents if fire not too hot may escape damage 3. Some insects seek fires- lay eggs in fire scarred trees with low defenses 4. Predators congregate at fires edge to catch fleeing animals

• 1. Release of light encourages productivity
• 2. Nutrient release taken up by newly emerged seedlings
• 3. Water dynamics change- evapotranspiration drops
• 4. Soil temperature increases with soot & full exposure to light
• 5. Soil cation exchange but in reverse mode- pH increases \

Fire Ecology Introduction	Ponderosa pine
Plant adaptations	Chaparral
Jack pine-hardwood forests	Long leaf pine
Douglas fir forests	Tall grass prairies
Back to Ecology Syllabus

emi/ 9-12/00