I drove through the Groveland area near Yosemite a couple of days before the Rim Fire started on August 17th. The local talk over Tioga Pass was then about the recent Aspen fire in the Sierra National Forest. The Rim fire has now burned 400 square miles of forest and cost $122 million to fight to date. What started as a 40 acre fire when discovered exploded to over 100,000 acres within 2 days. It is now the 3rd largest in California history.

Remote sensing satellite images indicate that virtually all the vegetation is dead on nearly 40% of the burned area. Chaparral and oaks will resprout but ecologist say it could take 30 to 50 years for the forest to reestablish itself. It scorched some of the last remaining old growth in the Stanislaus National Forest. Two years of drought and constant slow warming across the Sierra Nevada  worked to turn the Rim Fire into an inferno. For years forest ecologists shaded_fuel_brake_example.2048have warned that Western wildfires will only get worse. The fuels get drier and drier.

There have been two wildfires close to where I live in Felton, one of which was only 5 miles away on Martin Grade in Bonny Doon several years ago. How can I protect my home? Is there a landscape that is safer in a wildfire than another? Which plants burn more readily?

Many people think they have to clear everything within 30 feet of their house to truly have a defensible space.  This is unnecessary and actually unacceptable due to soil erosion and habitat destruction reasons.  We want to retain the character of this beautiful area we live in, provide the food and shelter that our native wildlife are accustomed to but also reduce fire risk.  For example, grasslands mowed to leave 4-6″ of height allow insects, reptiles, amphibians, and small mammals shelter, food and a place to reproduce. Leaving 4-6″ standing also provides some erosion protection and shades out some of the weeds that follow disturbance.

Fire safe landscaping is a term used to describe defensible space.  It can look like a traditional landscape.  The idea is to surround the home with things less likely to burn and place them to provide separation between canopies and avoid creating fire ladders.  Highly flammable plants should be placed, whenever possible, with low-growing and/or low fuel plants.

Many homes may not have 30 ft. between their house and the property line but following these guidelines will help.  Plants in this area need to be the slowest to ignite and should produce the least amount of heat if they do burn.  There are plants with some fire resistance which include drought tolerant California natives and Mediterranean climate selections.  The key to fire resistance, though, is maintenance and keeping the moisture in the foliage high.

For example,  Baccharis pilularis or dwarf coyote brush is generally considered highly flammable if its lush green top growth covers a hazardous tangle of dry branches and leaves several feet high.  Trim this plant down low in early spring, remove the dry undergrowth, follow with a light feeding and watering and the new top growth is now resistant to fire.

Other considerations may be as important such as appearance, ability to hold the soil in place and wildlife habitat value. Some fire-resistant California friendly plants are western redbud, monkey flower, ceanothus, sage, yarrow, lavender, toyon, California fuchsia and wild strawberry. Also consider coffeeberry, flowering currant, bush anemone, snowberry, California wax myrtle and evergreen currant. Fire resistant plants from areas include rockrose, strawberry tree, Chinese pistache, barberry, escallonia, oleander, pittosporum, bush morning glory and wisteria to name just a few.

Next week I will discuss plant spacing arrangement and maintenance to help you prepare a fire-safe landscape around your home.