Landscaping tips- Firewise

Firewise program logo.

How to add value to your landscape business promoting Firewise concepts

The home landscaping you design and construct for your clients adds beauty, value, and functionality to their property. It can also increase or reduce the chance of the structures on the property surviving a wildfire.

This Web page will provide tips for you as a landscaping professional to integrate Firewise materials and designs into your landscape design, and opportunities for additional business through mitigation of fireprone conditions on a client's property.

Home and yard saved from surrounding wildfire by firewise landscaping.

The situation

As more people move beyond the suburbs into the rural/urban interface, they are putting their homes in wild lands that have been shaped by fire, wildfire. In the wild, these wildfires renewed the forests and grasslands and did little damage to homes and property. With homes placed in this fire regime, homeowners are putting their homes at risk to wildfire loss. Rural fire departments, trained and equipped to protect homes in small communities are, unable to protect scattered homes from large wildfires. For example: May 2000, a wildfire south of Princeton destroyed four homes in a new development in a pine stand on the edge of wild lands. October 2000, an 8,500-acre wildfire that raced across the Carlos Avery Wildlife Management Area destroys four homes despite the efforts of 53 fire departments, the DNR, and the National Guard.

Homes in these same fires did survive. Why? Because they had defensible space, space around the homes that inhibited fire spread and allowed firefighters the opportunity to protect the home.

Graphic showing three zones of defensible space: structure zone, area within 30 feet from structures, wildland.

Defensible space

There are three zones around a home that need to be considered to reduce the risk of wildfire loss. The first zone is the structure zone - the area within 5 feet of the structure. If a wildfire is allowed to reach this zone, the home will likely be lost. Fire can reach this zone by traveling on the ground through flammable materials such as tall grass, wooden walkways, and fences, or by flying embers from a nearby fire that catch fire in materials within this zone.

The next zone makes up the defensible space and is the area within 30 feet of the structure. Any decks or outbuildings inside this zone are considered part of the structure and extend the zone 30 feet beyond them. This is the zone that, if properly landscaped, can prevent a wildfire from reaching the structure zone.

The third zone is the wild land or fuel reduction zone. This extends 100 feet beyond structures and is generally where the woods or other wild areas are. This is the area where excess fuel such as downed trees, heavy brush, and dense conifer plantations should be reduced.

Firewise landscape design tips

Zone 1 - Structure Zone or Intensive Zone

In this zone use nonflammable rock mulch or paving around the foundation and under decks. Favor block for retaining walls over ties. Ensure that there are no "wicks" that can carry fire to the structure. Wicks can be a wooden walkway connecting the yard to the deck to the house, or a wooden fence that is attached to flammable siding of a house. Use only low-growing Firewise plants and space them widely apart.

At least ten feet between trees will help break up contiguous fuels surrounding your home.

Zone 2 - Defensible Space or Extensive Zone

In this zone break up contiguous fuels with areas of well- irrigated and short-mowed grass or use gravel and rock paving. These are your firebreaks. Butterfly gardens, evergreen trees, and prairie patches should be created as small islands, separated from the structure by your firebreaks. Trees in this zone should be well spaced and maintained so their crowns are kept spaced at least ten feet apart. Prune off lower branches, up 6 to 10 feet, but no more than one-third of the live crown.

Zone 3 - Fuel Reduction Zone or General Management Zone

If this zone is predominantly evergreens, consider removing some trees (thinning) so that the crowns of the remaining trees are kept six to ten feet apart. Prune the remaining trees up six to ten feet. Remove tall underbrush so that there is a space of six or more feet between the tops of the under story plants and the lower branches of the over story trees. This reduces the "ladder fuels" that would allow a fire to climb into the tree crowns, starting a highly dangerous crown fire.

Firewise landscaping plants

There are no truly "fireproof" plants. Under the right conditions, all plants will burn. Those less susceptible to burning are firewise Plants. Firewise Plants have the following characteristics:

  • contain more moisture in their tissues, especially in spring and fall
  • have a low amount of volatile oils (most evergreens have high volatile oil sap)
  • accumulate less fuel by producing less litter or by staying small.
  • are compact and low to the ground
  • grow slowly, needing little maintenance such as pruning
  • have low water needs—when in drought, these plants often drop leaves, have smaller leaves or very succulent leaves that store moisture.

Deciduous plants have more firewise characteristics than evergreens. Also, when dormant, especially during Minnesota's spring fire season, deciduous plants have less fuel to carry a fire.

Plant a variety of native plants to help maintain vigor and health. Monotypes and exotics result in more insect and disease problems, resulting in more dead branches and plants, which are more fire prone. Mulch to reduce weed growth and conserve moisture. Avoid pine or cedar bark, pine needle mulch, or other materials that easily catch fire.

 

Maintenance

  • Keep grass mowed to less than a 6-inch height, and keep well watered.
  • Remove litter and dead vegetation from foundation plants and mulch.
  • Prune dead branches and thin trees as their crowns begin to touch.
  • Remove annuals after they have gone to seed, or when the stems dry out.
  • Prune off the lower six to ten feet of branches from trees, but no more than a third of the tree's height.
  • Remove flammable materials around buildings such as firewood piles and lumber piles.

Business opportunities

Whether you are a landscape architect or a yard service, there are opportunities where you can increase your revenue while providing a valuable service to your clients. As a designer, look for opportunities to implement firewise landscaping into the overall design. Highlight this firewise landscaping as a special feature of your design, to protect the home your client so highly values while adding beauty and functionality to the property. As a yard maintenance professional, use the tips found in this publication to identify fire- prone situations on your client's property. Offer to mitigate these situations as an additional service.