A diagram illustrating the “recommended” and “not-recommended” principles of firewise landscaping for Flagstaff area homes. (photo credit: Oregon State University)
This article first appeared in the Arizona Daily Sun.
After receiving less than 10 inches of snow for the entire winter period of December through February, it was such a blessing to have larger snow storms the first few weeks of March. Unfortunately, though, this year’s snow totals are nowhere near the over one hundred inches we usually receive in an average winter. Although we may receive some additional moisture in April and May, this dry winter is setting us up for a potentially extreme fire season ahead.
In order to reduce the likelihood of property loss due to wildfire, we need to address potential hazards of the vegetation around our homes. While the principles of firewise landscaping can be expensive and laborious in application, they can make a huge impact in minimizing the risk of wildfire damage to your property. The primary goal is to create defensible space by dividing your land into a series of zones, determined by distance from your home, in which you reduce flammable materials. Below, I review some of the key practices related to firewise gardening, however, for a complete description of the zonal concept and other topics related to wildfire preparation, please see the Flagstaff Fire Department’s “Ready, Set, Go, Action Guide” accessible on their website.
To begin, when selecting plants, focus on fire-resistant species. In general, fire-resistant species have open and loose branching patterns, create little dead wood and tend not to accumulate dry, dead material in their interiors. Their sap is water like and does not have a strong odor which is a sign of low resin content. Leaves are wide, flat, moist and supple. Good examples include succulents (i.e. hardy ice plant or agave), flowering herbaceous perennials (i.e. rudbeckia, gaillardia, or columbine) and deciduous shrubs like serviceberry and French lilacs. These features can be contrasted with plants that are highly flammable and should be avoided. These plants contain fine, dry or dead material, such as twigs, needles and leaves and/or loose or papery bark. Signs of high flammability also include leaves, twigs and stems that are aromatic when crushed indicating high volatile waxes, terpenes or oils or sap that is gummy, resinous and has a strong odor. Good examples of highly flammable plants are species that continue to be used in Flagstaff gardens including arborvitae and ornamental junipers.
Nate O’Meara is the Executive Director of The Arboretum at Flagstaff.
