More than 100,000 wildfires occur each year in the United States, according to the National Oceanic and Atmospheric Administration. Some are due to natural causes, such as lightning strikes, while others are accidentally — or, sadly, intentionally — caused by human beings. Regardless of their origins, these fires destroy an average of 4.2 million acres annually.
Most of these fires burn west of the Missouri River, in and around the Rocky Mountains and in the desert Southwest. These places are known for their startling natural beauty and their attractiveness to those seeking homes near wilderness areas. They also are known for high summer temperatures, low humidity levels and, particularly in recent years, parching drought. With tinder-dry vegetation and increasingly thick woodland growth due to decades of fire suppression, these regions tend to be ground zero for wildfires.
With increasing numbers of people living in the wildland-urban interface, where homes lie near and within wild areas, the risk also has increased dramatically for destruction of property during wildfire season. What can homeowners do to mitigate that risk?
Last week, we offered some tips on how to build or retrofit your home to be fire-resistant. Here, we’d like to offer some additional tips addressing what you can do to prepare your property for a wildfire and add extra lines of defense.
First, you will want to determine the risk level around your home: low, moderate or high.
Low-risk properties feature relatively flat terrain (a grade of 9 percent or less) and limited wildland, they incorporate native vegetation, they have a fire hydrant within 300 feet, and they offer easy access for fire trucks. All manmade fuels are at least 50 feet from the home, and no trees crowd the structure.
Moderate-risk properties have hilly terrain (with grades between 10 and 20 percent), a lightly forested wildland and trees near the house. Native vegetation is not part of the landscape, and manmade fuels are within 50 feet of the house — but the property offers access to fire trucks, and a fire hydrant is within 500 feet.
High-risk properties have steep terrain (greater than a 20-percent grade), thickly forested wildland within 100 feet of the home and trees within 30 feet. Native vegetation is not part of the landscape, manmade fuels are within 30 feet of the house, there are no fire hydrants, and the property has limited access for fire trucks.
The first zone of defensible space should extend from 30 to 100 feet from your home, depending on risk level. This space should be well-irrigated, and its landscaping should feature carefully spaced indigenous plantings and noncombustible elements, such as rock or brick.
The second zone should extend anywhere from 20 to 50 feet from the first, depending on risk level, and your irrigation system also must extend to this space. It may include small plants, shrubs and a few trees, if they’re carefully spaced about 10 feet apart. Remove all dead or dying limbs, and trees taller than 18 feet should have all limbs pruned within 6 feet of the ground. Absolutely no tree limbs should come within 10 feet of the house.
The third zone should extend approximately 20 to 50 feet from the second, depending on risk level. For example, in high-risk areas, the three zones together should comprise 200 feet of defensible space, versus 70 feet in a low-risk area. This zone is often called a “modified natural area,” which means homeowners need to thin trees throughout this zone and make sure all dangerous fuels, such as dead or dying bushes and trees, are removed.
Once you’ve set and cleared your zones, don’t forget to maintain them regularly. They won’t do their job if they become overgrown. This includes keeping grass and weeds trimmed and regularly removing brush piles, clippings and other deadfall. Also, be sure to eliminate manmade fuel sources. This can include replacing wood fences with metal, brick, stone or concrete ones; replacing wooden yard or patio furniture with noncombustible versions; and keeping your woodpile more than 30 feet from your home.
Think about ways you can create water sources. Connect at least 100 feet of garden hose to each of your outside taps, and purchase lawn sprinklers that can be used on the roof and around your property in the event of fire. Make sure you have an emergency generator to operate your water pump during a power failure, and consider adding a pond, cistern or even a swimming pool to your landscaping.
When adding to your landscaping, consider fire-resistant vegetation. If you’re a tree lover and live at higher altitudes, consider replacing conifers with aspen groves. Stands of aspen serve as fire buffers, while conifers, on the other hand, are prone to “torching,” allowing a wildfire to spread even faster. Replace at least some of the existing vegetation on your property with indigenous, fire-resistant plants, and remember: the plants nearest your home should be smaller and spaced farther apart than the ones in the zones farther out.
As much preparation as you can do to mitigate your risk of wildfire damage, you may still need to rely on the firefighters to finish the job. There are a few things you can do to make it easier for them to help you out.
As with fire-resistant home construction and retrofits, there are no guarantees that these mitigation steps will fully protect your property in the event of a catastrophic wildfire. But, they certainly can improve your odds — and provide an extra measure of safety for your family and for the firefighters who would risk their lives to defend your home.