Education Program

Chaparral and Fire

The California chaparral is a plant community composed of small shrubs and bushes that are adapted to fire. You can see the chaparral in the coastal mountains around San Diego, Los Angeles, Santa Barbara, San Luis Obispo, San Jose and other locations in the Coast Ranges, and also in the foothills of the Sierra Nevada and Klamath Mountains. The chaparral consists of tall bushes and small trees with dark green leaves. Most of the plants are less than ten feet high.

When we say plants are adapted to fire, we don't mean they need it, we mean they have ways of surviving a fire when it comes. It's a little like fire insurance. So what makes chaparral plants so special that they can survive the flames and heat of a wildfire?

A couple of sprigs of chaparral plants are shown above. These are of Manzanita (or 'little apple' in Spanish because of the appearance of the fruit, which is not a true apple), California Lilac (Ceanothus) which has beautiful blue. white, or lilac blossoms in the early Spring, Chamise which has tiny white masses of flowers on the ends of its branches of tiny green leaves, and Toyon (or Christmas Holly, named because of the red berries that grow on the small tree around Christmas time---it is the Holly in Hollywood).

These plants usually have really stiff, tough little leaves...they are usually quite shiny and look like they have a waxy covering. The leaves actually do have a waxy covering, which seals in the water inside the leaf during the hot summer months. The wax causes the leaves to burn really hot in a fire, like little candles.

Such waxy-leaf plants are called sclerophyls, and have sclerophyllous properties. Try saying sclerophyllous three times and then wipe the spit off the screen!

Chaparral is found where summers are long and hot, and where it might not rain for half a year or more. Hillsides are covered by stiff bushes that grow very close together, and you can't really walk through them without getting scratched up. During long periods without rain, the plants become very dry. Over time, dead wood may accumulate. Fuel for fire is available. Fire starts in chaparral because of lightning or because of careless humans.

Once fires start they can move across the hillsides very quickly. There is lots of heat given off. One fire in 1994 produced the heat of five atom bombs in a single hour. You sure didn't want to get in the way of that wildfire!

The waxy leaves and the dead wood cause a hot fire, and when it is over there is not very much left to see. Just a few burned stumps and sticks, piles of ash, and nothing apparently left alive. It is pretty depressing to look at.

So why was this good for the plants? How can dying in a fire help a plant? The answer lies in the seeds of some of the plants, and in the special nature of the blackened stumps of some of the others.

Now just imagine what it would be like to be a little seedling trying to grow under all of the big plants if they were still there. Down on the ground it would be too shaded for light to reach the new little leaves, and the big plants would gobble up all of the water. The little seedling would probably die, and there would be no room for it anyway.

After the fire there is space to grow, and there is water to drink and beautiful sunlight for energy. You might guess that all of the seeds would have burned up in the fire, but you would be wrong. In fact, the seeds may have been in the soil for years, just waiting for the fire. These seeds have a special outer coat that doesn't allow water to come in and cause the seed to sprout.

For some seeds, the outer coat is broken by the high heat of the fire. For other seeds, chemicals from smoke and charred wood prepare the seed for spouting.

The rain can then get into the seed, and up it sprouts into a world of wonderful light. It is kind of like the parent plant knowing it is getting old and woody, and deciding to get out of the way to make room for the kids.

The great heat of chaparral fire destroys the seeds of many non-chaparral plants, leaving more space and water and sunlight for chaparral seedlings.

Some species of chaparral can sprout from their stumps. These bushes keep a lot of energy in their roots, and after the top of the plant burns off, they simply sprout new leaves and branches. In this way, some plants may survive many fires, and could be hundreds of years old. Above we see a so-called "stump-sprouter" on the left, and a "seeder" on the right.

And so the plant species continue, and soon the hillside looks like it did before. The new sprouts and seedlings are really tasty for wildlife, and so life quickly returns. And the plants grow, get old, there is a fire, the plants grow, get old, there is another fire.....and on....and on....

However, even though chaparral plants are adapted to survive fires, too much fire is not a good thing. Too many fires, for example one every ten years, can cause a patch of chaparral to disappear because it doesn't have enough time to recover.

For a more complete discussion of chaparral communities, visit The California Chaparral Field Institute at CaliforniaChaparral.org.