California has a history of wildfires, and this year’s fires have been particularly fierce and damaging. Governor Brown has identified climate change as producer of fire dangers and described a future of more wildfires in the state.

Currently, Monterey Bay area residents are sympathizing with—and perhaps assisting—people in California’s northern and southern regions that are suffering significant losses from wildfires. They should also guard against the potential for wildfires in their own communities.

Good advice is available for protecting your home from external fire dangers.

Pre-fire management, which is the current jargon, includes reducing vulnerability to flying embers with tile roofs or roof sprinklers. Hardening your home in these and other steps is good practice when building, possible when renovating, and always less costly than having your home reduced to ashes.

Still, defensive landscaping is particularly important and cost-effective, and most relevant in this column on gardening. I have listed selected online publications at the end of this column. They describe more good ideas that could be summarized here, but here’s an overview of three basic concepts.

Provide Defensible Space

Landscaping that is close to the home should not support the movement of the fire. This includes spacing trees at least ten feet part when on level ground, and farther apart when the home is on elevated land.

Defensible Space Zones 1 and 2

The second level of defensive space extends to 100 feet around the residence. California’s Public Resources Code, Section 4291 requires these firebreak provisions for all properties that are near “any land which is covered with flammable material,” i.e., land covered by forest, brush or grass.

Current wildfires have demonstrated, however, that wind-driven embers can fly up to one mile during a wildland fire, so the practical need for defensible space applies to any residence within a mile of a wildfire.

Use Fire-resistant Plants

Within a home landscape’s defensible space, using fire-resistant plants adds to protection from fire. CalFire describes these characteristics of fire-resistant plants

• Store water in leaves or stems
• Produce very little dead or fine material
• Possess extensive, deep root systems for controlling erosion
• Maintain high moisture content with limited watering
• Grow slowly and need little maintenance
• Are low-growing in their form
• Contain low levels of volatile oils or resins
• Have an open, loose branching habit with a low volume of total vegetation

Succulent plants that several of these characteristics and can effectively slow or stop the spread of fire. Succulent plant specialist Debra Lee Baldwin recently described how succulents protected a southern California home that a wildfire threatened, as adjacent homes burned to the ground. Click here for her YouTube presentation.

There are many plants that resist fires to some degree. Large succulents are most effective. Baldwin recommends Paddle Cactus (Opuntia), Aloes, Aeoniums, Crassulas, and Sticks on Fire (Euphorbia tirucalli).

Avoid Flammable Plants

As the corollary to using fire-resistant plants, avoid flammable plants. These are plants that

• retain large amounts of dead material within the plant,
• produce a large volume of litter, or
• contain volatile substances such as oils, resins, wax, or pitch.

The most common trees that have highly flammable content are Eucalyptus, conifers, and all brooms (which often invade open areas). These plants can grow close together, making them even more prone to burst into flame. Keep them at least 100 feet from your home.

If you have been searching for a timely and constructive resolution to pursue during the coming year, a good choice would be to make your landscape both beautiful and fire-safe.

Source: Fire Watch Company

On-line Resources

California Department of Forestry and Fire Protection (CalFire): Ready for Wildfire (2017)

Pacific Northwest Extension: Fire Resistant Plants for Home Landscapes (2006)

UC Cooperative Extension: Safe Landscapes (2009)

The University of California, Division of Agriculture & Natural Resources: Home Landscaping for Fire