HOW DO YOU PROTECT YOUR HOUSE FROM FOREST FIRES?

by Whit Gibbons

March 24, 2003

The following question from Alabama could reasonably be asked anywhere in the country with a forested landscape.

Q. My home site consists of a few acres of pine and oak that I attempt to maintain in a natural and environmentally friendly manner. Trees and wildlife are left alone. I have glorious woods, enjoy watching the critters, and believe that I have a responsibility to keep this property, as tiny as it is, as close to nature as possible. When trees, bushes, and other plants die, I leave them where they fall, as would be the case in an untended forest. Natural clutter is the consequence, and the potential for a serious fire concerns me, should lightning trigger such an event. Can you suggest an environmentally friendly way of eliminating or reducing this problem?

A. I like your leave-nature-alone attitude, but have no easy answer for how to deal with the buildup of forest debris. I asked Dr. Ken McLeod, a botanist at the University of Georgia's Savannah River Ecology Laboratory who is familiar with southeastern forestry management for some recommendations.

He says, "You may defend your woods and house from fire in many ways, depending on numerous variables. First, lightning fires are a rare but potential problem for anyone. What generally happens is that lightning strikes a tree (the highest point in the landscape), runs down the tree and jumps to something else as it approaches the ground. That other object may be another tree, a shrub, or your house, which may catch fire directly from the lightning strike. To reduce this particular hazard, you could remove tall trees that are close to your house, although considering your wildlife interests, you may find leaving them an acceptable risk.

"The most effective action to reduce the flammable materials on the forest floor of your property is by controlled burning. Fire was very likely a natural feature of the landscape where you live, so you could simulate nature and periodically burn the forest floor, reducing the fuel for unintentional fires. This is not as horrible as you are probably imagining. Controlled burns are conducted in the winter, every five years or so, at a time when the forest floor is fairly damp. Following the fire you would still have a layer of organic matter (maybe half of what you started with). A controlled burn can be tricky and is best conducted by a professional forester who can assess environmental factors such as the humidity and wind characteristics, as well as how much fuel is present. A low intensity fire will be necessary to avoid damage to hardwoods, whereas pines are more tolerant of fire, due to greater bark thickness. Another way to reduce flammability is physical removal of some dead material on the forest floor.

"Less dramatic ways to protect a house from forest fires include not using highly flammable materials on the exterior. Brick with fiberglass/asphalt shingles is much less flammable than a wood-sided, wood-shingled house. Unfortunately, the latter style is more attractive on a forested lot. You can also minimize potentially flammable plantings immediately around the house's foundation, and keep those you have well watered. Or you can use plantings that require little water (Xeriscaping) and use a nonflammable mulch, such as gravel. In the fire at Los Alamos, New Mexico, several years ago, houses that were heavily landscaped caught fire and burned, while those with little or no landscaping did not. The difference was whether something flammable was immediately next to the house.

"Installing firebreaks at strategic points can also be effective. A safe firebreak is a bare zone about 10 feet wide, such as a road or disked area, with minimal flammable material. A firebreak helps keep a ground fire from spreading. If your property is part of a larger forest, a firebreak might not protect you from a crown fire in which the tree canopy is burning. Crown fires are rare but spectacular, as we have seen recently in the western United States.

"As you may have gathered, protecting your property from fire has no simple answer. Fortunately, the fire risk from natural sources is pretty low."



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