The home landscape and defensible space

May 19 – 25 had been designated Nevada Wildland Fire Awareness Week, and for good reason. A recent assessment identified 66 Nevada communities as “extreme” or “high” wildfire hazard areas. One of the major contributing factors to these undesirable ratings was the lack of adequate “defensible space” surrounding the thousands of homes evaluated in the assessment. If you haven’t already done so, now is a great time to make sure your home has a defensible space.

Defensible space is the area between your house and an oncoming wildfire where vegetation is managed to reduce the wildfire threat and allow firefighters to safely defend the house. In the event that firefighters are not available, having defensible space also improves the likelihood of your home surviving without assistance. Investigations of neighborhoods threatened by wildfire have consistently shown that having an effective defensible space can make the difference in a house surviving a wildfire.

The size of the area required for an effective defensible space varies based on the slope of your land and type of native vegetation present. It can extend 30 to 200 feet from the house. The steeper the slope and the more hazardous the native vegetation present, the greater the distance required. Proper selection, placement and maintenance of plants in this area is essential. Some defensible space tips to consider include:

  • Within the defensible space, remove dead vegetation, including dried grass and weeds, dead shrubs and trees, dead branches, fallen leaves and needles, dried flowers, and woodpiles.
  • Thin dense native trees and shrubs, such as sagebrush and pinyon pine, within the defensible space area, to leave some space between them.
  • Prune low tree branches to prevent a fire burning at ground level from igniting the tree canopy.
  • Within 30 feet of the house, do not plant evergreen trees or shrubs, such as Tam juniper or Austrian pine. Avoid creating large mass plantings of tall, dense shrubs in this area.
  • Within 3 feet of the house, do not use wood or bark mulches and emphasize the use of noncombustible materials, such as rock, gravel, pavers, brick, and concrete. You can also use irrigated herbaceous plants, such as lawn, low-growing flowers, and ground covers.
  • Do not place large shrubs below eave vents, in front of foundation vents, or adjacent to large windows.
  • Keep the canopies of deciduous trees at least 10 feet from the house.
  • Do not create a continuous cover of ornamental shrubs and trees that would connect native vegetation, such as sagebrush and pinyon pine, to the house.

In addition, make sure all exterior house vents are covered with one-quarter-inch or smaller wire mesh. Keep the rain gutters and the roof free of leaves and needles, and enclose the area under the deck. During fire season, keep all easily ignitable materials, such as baskets, paper, and dried flower arrangements, away from the house. If you have a wood shake or shingle roof, consider replacing it with a fire-resistant type.

Join us this Sunday, 9 a.m. – 5 p.m. at Moana Nurseries in Reno, 1100 W. Moana Lane or 11301 S. Virginia St., to learn more about creating a defensible space and to “Junk Your Junipers.” Pull out your junipers and exchange them for a free #5 preselected replacement shrub. There will be 50 free plants available at each location, on a first-come, first-served basis. Each household may receive one free plant.

For more information on defensible space, go to, or call University of Nevada Cooperative Extension, (775) 784-4848.

Ed Smith is a natural resource specialist for University of Nevada Cooperative Extension.