Fire smart landscaping doesn’t have to look like the desert

It’s hot, water is scarce and people want to keep their gardens green, by no means dry, so that they are less flammable in the event of a wildfire. Don’t sweat that. A healthy lawn and large trees are good protection against the ingress of flames, landscape experts say.

Irrigated areas with grass, along with patios, gravel paths, and driveways, can act as fire buffers. Plus, you may not have to mow your lawn that often. Higher green grass shades the roots, stores soil moisture and requires less water.

The priority is to efficiently irrigate and create a sleek and green defensible space that is free of debris to slow, resist, or stop the spread of ground fires, said Weston Miller, an urban gardener at Oregon State University Extension Service.

According to the Turfgrass Water Conservation Alliance, lawns can be up to 30 degrees cooler than concrete or asphalt. Still, many homeowners choose to replace grass with low water plants, ground cover, or hardscape environments made of concrete, brick, pebbles, or sand.

Water conservation is more urgent than ever as Oregon has entered summer after an exceptionally dry spring and more than 90% of the state is classified as a “severe drought” according to the US Drought Monitor.

To reduce water use, Amy Whitworth, a Portland garden designer and educator who owns Plan-it Earth Design, recommends an organic lawn, which is lawn-like ground cover that stays green in the summer without additional water. She likes a mix of micro clover and broad-leaved plants like daisies, yarrow, and other drought tolerant plants that can be mowed.

Green, fire-resistant yards are on the minds of many homeowners after last year’s devastating forest fire season, Whitworth said.

This year’s dry, hot summer has more people looking for ways to reduce the vulnerability of their home and community. Cities and other government agencies want everyone to thin out and remove dead and high-risk vegetation.

“It is time to prepare your defensible space,” said Whitworth, “especially if you live in an area with a lot of canopy, especially evergreen trees, or in wooded areas on slopes.”

Designed by Amy Whitworth of Plan-it Earth Design in Portland.Plan-It Earth design

After those hot days, what you learn about your plants’ water needs can help you reevaluate what is growing around your home. Native plants, succulents and those that thrive in other semi-Mediterranean regions with summer drought are not only easy to care for, but also less thirsty.

And most are fire-resistant, which means that they store water in their leaves, stems, and sap and don’t produce dead and fine materials like needles. Deciduous trees are more fire resistant than evergreens.

Neither plant is fireproof, but many are more difficult to ignite. OSU Extension’s free downloadable guide, “Fire Resistant Landscaping Plants for the Willamette Valley,” lists ground cover, perennials, shrubs, and trees that can thrive without much additional water while preventing wildfire.

Fire experts say to avoid plants with gummy sap and high resin and oil content that can burn easily. Rosemary, lavender, and other plants with leaves that are aromatic when crushed may be low in water requirements, but they contain essential oils that make them flammable, Weston said.

Fire-smart landscaping doesn’t have to look like the desert. On the flame retardant list are some of Oregon’s signature trees, such as dogwood and Japanese maple.

Oak trees and other mature trees are more resilient to damage from forest fires and, when pruned, can act like a living wall, reducing the intense heat of the fire and blocking the embers in the air, according to Oregon forestry experts.

Make it easy for yourself: choose low-growing, drought-tolerant, fire-resistant plants. Place them apart from a home and water them when they need it.

When planning and installing fireproof landscaping, the Oregon Department of Forestry also encourages people to consider factors such as the area’s fire history and prevailing winds.

Landscape designer Lisa Meddin, who owns Harmony Design Northwest in Portland, does not place tall plants near a structure, uses a minimum of foundation planting, and bundles plants at the edge of the property instead of continuous borders.

She integrates native plants into ornamental beds and uses lush ground cover instead of mulch. A small amount of mulch around the base of plants or trees will hold in moisture. But bark or wood chips can also pose a fire hazard. Instead, use inorganic mulches like gravel or small stones.

Fire-wise landscape

Designed by Amy Whitworth of Plan-it Earth Design in Portland.Plan-It Earth design

Whitworth has other tips for preparing a landscape for fire and drought:

  • Before you buy drought-tolerant plants in the summer heat, you should take a critical look at your existing landscape. Which plants thrive without additional water?
  • To test this, slowly reduce the amount of water week by week and see which plants show a dramatic response. Consider removing them from your landscape or grouping thirsty plants in a zone that will receive a higher water rate.
  • Do they touch the house from the surviving plants? This allows a ground fire to spread to the siding or roof. Prune branches and large shrubs, and remove other vegetation that could bring fire to the canopy.
  • Keep the gutters free of needles, dried leaves, and twigs to prevent the embers from igniting dried plant matter.

Whitworth also recommends requesting a site visit from volunteers with the Backyard Habitat Certification Program. They advise you on how to add drought tolerant, native plants for the fall and winter seasons.

Fire-wise landscape

The California Department of Forestry and Fire Safety (Cal Fire) released this representation of the defensible space created around a home.California Department of Forestry and Fire Protection

Roger Pearce lives in Ashland near the intersection of wilderness and city, surrounded by natural vegetation, and says the city, the Lomakatsi Restoration Project, and the US Forest Service have cleaned up their side.

And for the past five years, Pearce and his neighbors have also been busy removing flammable madrons, pine trees, and junipers from their homes. Branches have been cut when they are less than two meters above the ground to prevent a fire from climbing and spreading.

Newer landscapes have deciduous maples, magnolia, and lilac trees and a variety of low grasses, shrubs, and flowers, but no bark, he said.

A government grant was an incentive for some in the neighborhood to remove combustible plant material, but the bigger motivation was the Almeda Fire 2020, which is still a burning reminder of the region’s vulnerability.

Still reluctant homeowners nudge new views of beautiful landscapes designed to keep a fire out.

“It doesn’t look like the desert outside of Las Vegas,” said Pearce, who was standing on his street near an ocher concrete retaining wall surrounded by a fragrant evergreen Mexican orange bush.

Comradeship also plays a role in this ongoing collaborative effort. Friendly education takes place on the doorstep, no lectures. Instead of threats of fines for violations, there are offers of help and invitations to working groups.

When the huge green waste bin parked in the street is filled to the brim with 20 cubic meters of collected plant debris, neighbors known as “elves” stamp the leaves down. “I’m the heaviest elf,” joked Pearce.

For more information on fire safety, please visit the Oregon Department of Forestry’s YouTube channel and website:

– Janet Eastman | 503-294-4072

jeastman@oregonian.com | @janeteastman

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