Master Gardeners: Wildfire prevention at home
Oct. 1—Last year I wrote an article on planting for safety in your garden. It addressed issues around potential plant toxicity to people and pets. With the recent catastrophic wildfire in Maui, I thought it might be a good time to reflect on plant safety for your home as well.
After the fire, articles about the role of invasive grasses in wildfires appeared in the New York Times, Washington Post, PBS, Science News and other media sources. Since we are surrounded by grasslands in Santa Fe County, I was curious about the difference between native and nonnative grasses as fuel for fire.
In Maui, as more sugar cane plantations were idled, grasses from as far away as Africa were introduced as forage, and they quickly spread. "These grasses are highly aggressive, grow very fast and are highly flammable," according to Melissa Chimera, coordinator of the Pacific Fire Exchange. They are drought resistant and grow fast when it rains, as much as six inches a day. In Santa Fe we don't have the same grasses, but there are plenty of non-native grasses and weeds here.
None of this is news. The role of grass in fires has been studied for decades. Eva Frederick, writing in Science in 2019, reported, "Ecologists mapped wildfires across the United States from 2000 to 2015 and compared them to the locations of 12 species of nonnative grasses." Researchers found "for at least eight species—which come from Europe, Africa, and Asia—more grass meant more fires."
A good example in our area is Kochia scoparia, aka kochia. It is native to Asia and came to the U.S. by way of European immigrants who, ironically, planted it as an ornamental called burning bush. The name probably refers to its reddish fall color, but when dry, it is highly flammable. Such plants are pyrophytic, meaning they have a high resin or oil content that burns quickly and hot. Cheat grass (Bromus tectorum) is an invasive grass now common in our area. It is considered a pyrophytic grass, and wildfire experts suggest mowing it or removing it.
Around our homes we can benefit from opting for "fire wise" landscaping. The five-foot zone near a home is called the "home ignition zone," so it's an important area to look at. Native plants can support our safety goals since they are less weedy, with less litter and smaller size. Native grasses in particular have moister tissue and don't contain nearly the amount of volatile oils and resins found in nonnative pyrophytic plants. The same applies to succulents. That means less fuel for fire.
There are beautiful and locally popular ornamental grasses, such as Chinese silver grass or maiden grass (Miscanthus sinensis), that are lovely but can be invasive and become quite large. More firewise choices are ground covers and lower-growing grasses. If you have taller grasses, keep them well maintained. Don't over irrigate or over fertilize, clean out dead plant material and space them to prevent a concentration of fuel. Maintenance is key to fire safety.
Many residential neighborhoods and homeowners associations participate in FireWiseUSA, aimed at helping residents reduce wildfire risks. When I read that the Maui fire started as a grass fire but became a "house-to-house" fire, I was relieved to know I live in such a firewise community.
For more information on creating a group to address wildfire risk in your neighborhood, visit www.nfpa.org and click on the "Public Education" tab. It offers education and guidance on creating firesafe landscapes.
Master Gardeners: Wildfire prevention at home
