Defensible space is the area between a house and an oncoming wildfire where the vegetation has been modified to reduce the wildfire threat and to provide an opportunity for firefighters to effectively defend the house. Sometimes, a defensible space is simply a homeowner's properly maintained backyard.

THE FIRE DEPARTMENT IS SUPPOSED TO PROTECT MY HOUSE, SO WHY BOTHER WITH DEFENSIBLE SPACE?

During a major wildfire, it is unlikely there will be enough firefighting resources available to defend every home. Firefighters may have to select homes they can most safely and effectively protect. Even with adequate resources, some wildfires may be so intense that there is little firefighters can do to prevent a house from burning. The key is to reduce fire intensity as wildfire nears the house. This can be accomplished by reducing the amount of flammable vegetation surrounding a home. The most important person in protecting a house from wildfire is the owner.

DOES DEFENSIBLE SPACE REQUIRE A LOT OF BARE GROUND IN MY LANDSCAPE?

No. Unfortunately, many people have this misconception. While bare ground is certainly effective in reducing the wildfire threat, it is unnecessary and unacceptable due to appearance, soil erosion, and other reasons. Many homes have attractive, well vegetated landscapes that also serve as effective defensible space.

HOW BIG IS AN EFFECTIVE DEFENSIBLE SPACE?

The necessary distance for an effective defensible space is not the same for everyone. Slope and type of wildland vegetation growing near the house will determine how much space will be needed. See the section entitled “Creating An Effective Defensible Space” for specific information.

DOES HAVING A DEFENSIBLE SPACE GUARANTEE MY HOUSE WILL SURVIVE A WILDFIRE?

No. Under extreme conditions, almost any house can burn. But, having defensible space will significantly improve the odds of your home surviving a wildfire.

WHY DOESN’T EVERYONE LIVING IN A HIGH WILDFIRE HAZARD AREA CREATE A DEFENSIBLE SPACE?

Some individuals believe “it won’t happen to me”, while others think it’s costly and others are simply unaware of the benefits.

WHAT IS THE RELATIONSHIP BETWEEN VEGETATION AND WILDFIRE THREAT?

Many people do not view the plants growing on their property as a threat. But in terms of wildfire, the vegetation adjacent to their homes can have considerable influence upon the survivability of their houses. All vegetation, including plants native to the area as well as ornamental plants, is potential wildfire fuel. If vegetation is properly modified and maintained, a wildfire can be slowed, the length of flames shortened, and the amount of heat reduced, all of which assist firefighters in defending the home against an oncoming wildfire.

DOES CREATING A DEFENSIBLE SPACE REQUIRE ANY SPECIAL SKILLS OR EQUIPMENT?

No. For the most part, creating a defensible space employs routine gardening and landscape maintenance practices such as pruning, mowing, weeding, plant removal, appropriate plant selection, and irrigation.

DOES DEFENSIBLE SPACE MAKE A DIFFERENCE?

Yes. Experience shows houses with an effective defensible space are much more likely to survive a wildfire. Defensible space gives firefighters a greater opportunity to effectively and safely defend the home.

HOW DO I CHANGE THE VEGETATION ON MY PROPERTY TO REDUCE THE WILDFIRE THREAT?

The objective of defensible space is to reduce the wildfire threat to a home by changing the characteristics of the adjacent vegetation.
Defensible space practices:

• Decrease the amount of flammable vegetation.
• Shorten plant height.
• Alter the arrangement of plants.
• Increase the moisture content of vegetation.

This is accomplished through the "Three R's of Defensible Space".

Removal

This technique involves the elimination of entire plants, particularly trees and shrubs, from the site.

Reduction

Examples of reduction are pruning dead wood from a shrub, removing low tree branches, and mowing dried grass.

Replacement

Replacement is the substitution of less flammable plants for more hazardous vegetation. For example, removal of a dense stand of flammable shrubs and planting an irrigated, well maintained flower bed.