Defensible Space

What is a defensible space?

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.

The Three R's of Defensible Space

Removal: This technique involves the elimination of entire plants, particularly trees and shrubs, from the site. Examples of removal are cutting down a dead tree or cutting out a flammable shrub.

Reduction: The removal of plant parts, such as branches or leaves, constitute reduction. Examples of reduction are pruning dead wood from a shrub, removing low tree branches, and mowing dried grass.

Replacement: Replacement is substituting less flammable plants for more hazardous vegetation. Removal of a dense stand of flammable shrubs and planting an irrigated, well maintained flower bed is an example of replacement.

FIRE ZONES FOR WOODLAND HOMES

ZONE 1: 5 FEET FROM THE HOUSE

This area, closest to the house, is the most critical for fire protection. Have nothing flammable next to the house, including tall grass, evergreen trees and shrubs, trees that overhang the house or deck, leaves, brush, firewood piles, bark, mulch and other burnables. Clean gutters, roof and deck of flammable debris. This zone does not have to be barren. Maintain a well-kept lawn, or use crushed brick or river stone gravel instead of mulch. Use raised beds, large decorative rocks, stone walkways, patios, or other features to create visual interest while maintaining a fuel break for forest fire safety.

ZONE 2: 10 FEET FROM THE HOUSE

Maintain a well-kept lawn and avoid evergreens that catch fire easily and burn quickly. Occasional trees and shrubs should be at least 10 feet from the house. Space trees with 10-15 feet between tree crowns and prune trees 10-15 feet up from the ground.

A pond or swimming pool can act as both a firebreak and an emergency water supply for firefighters. Freshly tended flower beds, herb or vegetable gardens, rock gardens, stone walls and driveways can also act as firebreaks. Avoid "fire ladders" that allow fire to climb from the ground into tree branches. Do this by pruning trees, spacing tall trees away from medium-sized trees and by using ground covers or small plants under tall trees.

ZONE 3: 30-100 FEET FROM THE HOUSE

Rake or use a leaf blower to remove leaves and twigs at least 30 feet from the house and up to 100 feet on the downhill side. If you live in a pine forest, maintain a safety zone at least 75 feet on all sides of the house. Firewood and other burnables should be stored at least 30 feet from the house to help keep fire from spreading to or from your house. It also provides a space for firefighters to defend your house from fire.

Prune and thin trees so there are no dense stands or tree tops touching. Keep shrubs small, maintained, and free of dead materials. Control brush and weeds annually. Steep areas can be terraced to slow down wildfires. A stone wall can also act as a fire barrier on very steep slopes.

THE HOUSE: BUILD WITH FIRE IN MIND

Build your house on a level location. Houses overhanging steep slopes are very vulnerable to forest fires. Enclose any open space underneath decks with screen to prevent embers from entering. Use fire resistant building material for both the siding and the roof. Avoid wood shake roofs for woodland homes. Make sure firefighters can find and reach your home.

The Firescape

  • A home in a woodland setting is usually surrounded by forest fire fuel and is in real danger if a wildfire is on the loose.
  • Firewise Landscaping can create a line of defense against the threat of wildfire by creating a safety zone or defensible space around your home.
  • The goal is to break the chain of flammable fuel between your home and the forest. Examine your yard. What can catch fire and carry this fire to the house?

Be Guided By Nature's Patterns

You can landscape for fire protection while maintaining a natural look to your surroundings. Work with the plants native to the site, using the pattern found in nature. Also, consider hardiness zones when choosing new plants. The placement of plants and trees is just as important as the species when planning fire safety.

All Plants Burn!

There are no fire proof plants, but some plants are more fire-retardant than others. Use these considerations when choosing plants and trees for your yard.

Choose plants and trees with:

  • A high moisture content in the leaves
  • A low oil or resin content (avoid cedars and pines).
  • Limited foliage, and few dead branches.
  • A lower overall height.
  • An open, loose branching appearance.
  • Easy maintenance and pruning.
  • Drought resistance.

Suggested Large-Sized Trees:

  • Oaks
  • Maples
  • White Ash
  • Hickories
  • American Linden
  • Black Gum
  • Yellow Poplar
  • Hackberry
  • Ginkgo

Suggested Medium-Sized Trees:

  • Golden Raintree
  • Crape Myrtle
  • Yaupon Holly or Deciduous Holly
  • Flowering Dogwood
  • Magnolias
  • Redbud

Suggested Shrubs:

  • Holly
  • Japanese White Birch
  • Azalea
  • Nandina
  • Gardenia
  • Forsythia
  • Red Leaf Barberry

Suggested Ground Cover:

  • Wilson Ivy
  • Liriope
  • Ajuga
  • Euonymus

DO NOT Plant these within 30 Feet of the house:

  • Loblolly Pine
  • Shortleaf Pine
  • Eastern Red Cedar 

For more information go to Firewise.org