In recent years, out-of-control wildfires have devastated entire neighborhoods and communities. While not confined to the western part of the United States, areas like California are at increased risk because of their topography. If you live and work in an area that is prone to wildfires, there is much you can do as a landscape professional to decrease the risk of property (and life) loss through thoughtful plant and material choices and placement.
Whether you are a designer, a contractor, or lead a maintenance team, you can contribute to making your clients’ properties safer for everyone.
Why are wildfires more prevalent now?
Fire is a natural, even necessary, part of the ecosystem — when a fire in a forest turns dead or decaying plant material into ashes, the nutrients return to the soil. Smaller, competing weed plants are destroyed and seeds for eventual mature forest cover are scarified and germinate. The problem we’ve been seeing lately is that more homes are being built outside of urban areas in previously undeveloped territory, and the properties are then vulnerable to naturally occurring wildfires.
How to create a firewise landscape
While you can’t change topography, you can change the way you design and plant the landscape around a house and the property as a whole to lessen the risk of wildfire devastation. And while no plant or material is immune to the ravages of fire, there are some choices that are much better than others, and which create a safer boundary in what’s called the “defensible space.”
Defensible space is the buffer around a property that improves the chances of surviving a wildfire — often considered the 100’ perimeter of the property, but also referencing the 30’ around a house if it’s a smaller property. Here’s what you need to know.
It’s not just a matter of having plants around a house — it’s a matter of selecting the right plants. In general, deciduous plants with an open, loose structure generate less flammable material than plants with dense canopies or plants that hang onto their leaves throughout the winter. (Beeches and some types of oaks are deciduous, but they hold onto their dry leaves. Not great in fire prone areas.) Slow growing plants are good choices, as are those that will re-sprout after a fire, which means less work replanting. Plants that have a high tolerance to salt have also shown themselves to be highly fire resistant.
Say “yes” to these plants
Plants that hold water are much less likely to burn quickly and spread the fire from plant to plant, so specify herbaceous plants and succulents (lots of water in their leaves), including annuals, perennials, bulbs (another “juicy” leafed plant), most groundcovers, lawns (where it makes sense, environmentally), and conservation grasses. Deciduous trees and shrubs as well as shrubs that are less than 2’ tall are also valuable choices when it comes to fire defense.
For a full listing of great firewise plants, click here for a list.
Say “no” to these plants
Evergreen trees and shrubs spread fire more quickly, as do waxy, resinous plants like junipers, pines, and arborvitae, so plant those away from the house in fire prone areas. Additionally, avoid plants with lots of fine, twiggy material, as they act as kindling to wildfires.
Firewise landscaping tips & techniques
Plant palette settled, make sure you incorporate these techniques into your firewise landscape design.
Use fire-resistant hardscaping in a thoughtful manner
Opt for island beds or pocket plantings within the defensible space, and use hardscaping features such as pathways or gathering areas to create mini firebreaks between planting spaces. Use materials like gravel, stone, or decomposed granite for these areas.
Space plants and materials appropriately
Avoid large, continuous mass plantings around the property or up against the house. Within 3-5’ of the house, opt for rock, gravel and other hard surfaces combined with well-irrigated herbaceous plants and succulents. Within 30’ of the house, plant deciduous trees with at least 30’ in between tree canopies to avoid fire leaping from tree to tree or tree to house.
Conduct detail-oriented maintenance for the entire landscape
Regular maintenance is an invaluable defense against wildfire damage. Keep grass mowed and trimmed, plants well watered, and trees properly pruned and thinned out. It is especially important to stay on top of maintenance for landscapes with high concentrations of native plants. Many native plants are meant to have fire as part of their life cycle, so pay close attention if large swaths of dry vegetation seem to be building up and remove it.
Rake and remove leaves and twigs, as well. Any excess brush or small trees or shrubs should be removed as well — remember to create space between plants and plantings for those necessary firebreaks.
Again, as part of the green industry we can’t prevent wildfires from happening, but we can help mitigate damage for our clients with thoughtful design.