A cursory observation of wildfire’s aftermath prompts the widely held conclusion that fires are destructive. While this is true when fire approaches the wildland-urban interface, fire is a natural and important part of the environment. Fire clears out spent plant matter and incubates new life. In areas where wildfire naturally occurs, some plant species have adapted to take advantage of it and even require fire to germinate or reproduce. Fire can prepare soil for new growth replenishing nutrients in the soil and removes invasive species that compete with native vegetation for resources.
Some species thrive in post-burned areas. Burned trees provide habitat for birds. Coastal redwoods on The Preserve are highly resistant to fire. A year after a spate of fires swept Northern and Central California in 2008, scientists observed redwoods that had been scorched were covered anew in green foliage. The Preserve’s maritime chaparral, a fire dependent vegetation type, actively requires fire for many species to reproduce. Examples of these species include the endemic manzanita found only in California that has carefully adapted to respond to the state’s ecological disturbances, and fire-chaser beetles that can detect the infrared radiation of fire and swarm towards it. These beetles will make the journey from over 60 miles away to lay their eggs in scorched trees. Their larvae are wood-eating and wouldn’t survive healthy trees’ chemical defenses.
Historically, some land management misunderstood the importance of fire and called for its active suppression. When wildfires are suppressed, however, fuel builds up, creating the likelihood for an even larger and less manageable fire. When these pent-up fires burst, they carry more potential harm. For example, very intense fire can burn out organic material in soil, which causes erosion; soil particles can become hydrophobic, or unreceptive to water, which causes rain to run off instead of soak in, further promoting erosion.
Fire and forest can be thought of in terms of a predator-prey relationship — a vital dynamic in any natural system. On the Preserve, we benefit predator populations like raptors, coyotes and bobcats which far from destroying rodents indiscriminately, keep rodent populations healthy and in check. In much the same way, younger, healthier trees are most likely to benefit from fire, which burns through older trees and vegetation. Fire serves as insect pest control by killing older or diseased trees. Ashes after a fire then return nutrients stored in these older plants back to the soil. As fires remove undergrowth, more sunlight reaches the forest floor, encouraging growth.
After a fire, a forest goes through a process called ecological succession, which refers to the stages a forest goes through to return to a healthy mature forest. The first colonizing species after a fire are intrepid herbaceous species like grasses and weeds. More cautious, slower growing trees arrive behind them, followed by early successional trees like pines. Ultimately, longer lived hardwoods such as oak and hickory join the community, supplying forest canopy.
Historical data suggests early California people understood the benefits of fire-induced plant diversity at various stages of succession and used fire as a tool to reap these benefits. Today, the U.S. Forest Service is working with Native American leaders to revitalize land management practices that preserved watersheds, eased effects of drought and created fire barriers, including the use of controlled burns to promote useful plants and discourage larger, more intense fires.