Your Garden and Fire,It’s Complicated

There are common-sense ways of reducing fire risk. Reducing vegetation can reduce fire intensity and speed. Keep flammable mulch and excess fuel away from structures. Create gaps in combustible fencing near structures. Make areas around structures lush and adequately watered. In a wind-driven fire-storm, no habitat with any vegetation is safe though, and people should be prepared to speedily evacuate and save themselves, loved ones and pets. In the Tubbs Fire (2017), wind-driven fires crossed freeways and burned buildings surrounded by parking lots.

California, with a few exceptions, is fire-prone given its long dry season exacerbated by periodic droughts, dry wind storms and the like. It has been this way for hundreds of thousands of years, though the climate has had wetter and colder periods cycling through this vast expanse of time. When the Native Americans appeared, they developed methods of using fire to enhance the products they needed to survive, opening up rangeland, renewing food and fiber resources, and the like.

 Native Americans were well adapted to the use of fire. Extensive areas across the Great Plains burned every three to seven years 

Native Americans were well adapted to the use of fire. Extensive areas across the Great Plains burned every three to seven years

Thus by the time the Europeans arrived and dominated the state, the existing landscapes represented a certain balance between man and nature. Most of the native plants had worked out ways to survive or vigorously regenerate from the cycles of fire, and many plants came to depend on the periodic openings created by fire. Most of our major plant communities (associations) are shaped by the fire frequency. 

With the change of cultures, fire became the enemy, and fire suppression the norm. More development shifted into wild areas. The vegetation shifted significantly. Hundreds and then thousands of new plants, often weedy, crowded in, often displacing the native flora. The native flora also crowded itself. Most natural areas we see today are often undermanaged and overgrown compared to what they might have been in 1800.

Calistoga Retreat natural area. Roger Raiche is considered among the top experts in the world on California native plants and natural plant habitats. 

As a landscape contractor and manager, when we manage natural landscapes and country properties, we often “reset” the plants/plant communities to a more open, reduced vegetation state. Weedy vegetation removal can make a huge difference to start, especially with thickety woody weeds like French, Scotch or Spanish broom, Gorse, Armenian blackberry, Cotoneaster, Pyracantha, etc. Often the native vegetation has become crowded with excessive numbers of native trees and shrubs – as they are no longer edited by routine fire that killed seedlings.

Removing senescent trees, and extensive thinning of oaks, bay, and especially Doug fir seedlings, can immediately open up an impenetrable woodland and turn it back into an attractive park-like environment. New technology with forestry chippers and mowers are making this increasingly viable as a management process. The native herbaceous understory has space to come back, adding more diversity and pollinators and habitat. Many understory shrubs can be renewed by cutting back – often to the ground – making them more vigorous and attractive with less dead material.

Extremely flammable habitats like grassland or chaparral can also be managed by thinning or mowing. In areas where rare or unusual native plants occur, we give priority to preserving these so future generations can share in our rich diversity. Another value to opening up areas is that it makes it easier to create trails which makes access to even remote areas easy, attractive, and fun. People who can get around their property are more likely to manage it. Management is an ongoing process but can be broken up into phased improvements depending on priorities.

Many fire-safe models are based on properties larger than in many residential areas we see in Sonoma Co. Smaller, more traditional residential landscapes can be cleaned up to reduce excessive growth. Replace extremely fire-prone plants. But when your neighbor is only ten feet away, and there is a wood fence between you, it’s a challenge to comply with new standards being created. Aesthetically, having only lawn or high water annuals or gravel next to your house may not be desirable. This can create an excess use of precious water or moisture against your home. Plants also play an essential role in creating fresh air, capturing carbon, and adding to our sense of well being. Mulch and leaf litter help prevent weeds, keeps the soil cool and moist, and helps microorganisms that help keep plants healthy.

People often want to live surrounded by plants. They crave shade in the summer, they want a yard with diversity and mystery. They want a mix of heights, colors, and forms. The oversimplification of “fire-safe” landscaping guidelines don’t address the underlying macro issue of the fact that we live in an environment where fire is part of our ecology. Our society has villanized this and mistakenly mismanaged our environment to the point where fuel levels have built up to a point where catastrophes are common. By individually using some of our strategies, you can reduce your risks, help the environment, and develop your love of gardens.

by Roger Raiche David McCrory, Planet Horticulture