Scientists worry about chaparral habitat's survival

By: BARBARA HENRY - Staff Writer | Saturday, October 23, 2004 7:38 PM PDT ∞

Conventional wisdom goes that fire is a fact of life in Southern California, so native plants know how to cope with it.

But as the one-year anniversary of the Cedar and Paradise fires approaches, some biologists are asking how many fires the county's native chaparral and coastal sage scrub habitats can handle in a given time period.

"The Cedar fire, in particular, burned areas that had burned seven years before," said Rick Halsey, a biologist whose book "Fire, Chaparral and Survival in Southern California" is due out in December. "Especially in the Miramar area, I don't think that's ever going to come back."

The chaparral and coastal sage zones ---- shrub-dominated plant communities with an abundance of drought-tolerant species ---- need some fire to clean out built-up brush and help seeds germinate. The problem is that the shrubs have trouble recovering if the area burns twice in a 10-year period, Halsey said.

The more human development pushes up against Southern California's wild lands, the greater the potential for fires. If the frequency of fires increases, the shrub areas transform into grasslands where non-native, weedy species predominate.

Biologists monitoring the state of plants and animals following last October's 280,000-acre Cedar fire and 57,000-acre Paradise fire said they have great news to report about the recovery of some areas, and not-so-good news about others.

Life returns

Some 63,000 acres, or about one-seventh of the Cleveland National Forest, burned in the Cedar fire. This spring, flowers ---- including rarer things such as the velvety false lupin and the Cuyamaca larkspur ---- spread across the burned-over areas, and pine tree seedlings sprouted.

"The bird populations are starting to bounce back," said Kirsten Winter, a national forest biologist, as she discussed the forest's status a year after the Cedar fire.

Among the species using the fire-charred lands are rock wrens, sage sparrows and black-headed grosbeaks. The sage sparrow is considered a "species of concern" by biologists, so seeing it is a good sign, Winter said.

Creatures that don't do well in the first few years after a fire include the endangered California gnatcatcher, the California thrasher and wood rats because they like thick brush, she added.

Wood rats need large sticks in order to build their massive nest structures, so "they're obviously not very happy now," Winters said.

Most of the burned areas in the Cleveland National Forest were in forest or chaparral habitat, but 10,000 to 15,000 of the acreage was coastal sage scrub. Those plants are more fire-sensitive and are located in the lowland areas near human development, Winter said. Some of the coastal sage habitats have burned so often in recent history that they are turning into grassland, she added.

For example, she said, drive near the Country Estates community near Ramona.

Lessons learned

A next-door neighbor of the Cleveland Forest, the Cuyamaca Rancho State Park had nearly all of its land holdings burn in the Cedar fire.

"Out of the 27,000 acres in the park, 300 survived ---- the park was devastated," said Deborah Knapp, education coordinator for the nonprofit Anza Borrego Institute, a research organization that handles projects in the Colorado Desert District of the state parks system.

The institute hosted a two-day symposium earlier this month on how the state park has recovered from the fires and what can be learned from that recovery. State biologists and private researchers presented their findings on everything from the fire's effect on the mountain lion population to the survival rate of rare plants, including the rare Cuyamaca cypress.

Some areas of the park have had "vigorous rejuvenation," while in other spots, only blackened ground greets visitors, Knapp said.

"There's places that it's shocking to see the scars from the fire ... but there are other parts of this park that you would never know there was a fire ... trees have regrown, animals are coming back," she said.

The rapidly moving fire killed many mammals as they tried to flee, but four out of the five mountain lions sporting electronic monitoring collars as part of a UC Davis research project survived the blaze, the institute reports.

Standing tall

Some of Cuyamaca Rancho State Park's oldest inhabitants ---- trees, including sugar pines as old as 500 years ---- were reduced to ash. Many, perhaps 80 percent or more, of what is believed to be the world's only grove of Cuyamaca cypress trees burned in the fire, the institute reports.

The juniperlike evergreen trees, which are found on the southwest side of Cuyamaca Peak, are caught in an awkward bind: The trees are very sensitive to fire damage ---- if they are scorched by flames, they won't survive, said Jim Bartel, field supervisor for the U.S. Fish and Wildlife Service.

While the trees can't take fire, their cones need the heat of a forest fire to open and release the seeds that will become future trees, said Bartel, who has studied cypress trees since the 1970s.

The trees count on having infrequent fire events.

"The concern is, if fire is too frequent, basically the stands will disappear," he said.

What the area needs now are no more fires for a good three decades, so it will have time to produce cones, he added.

Contact staff writer Barbara Henry at (760) 901-4072 or bhenry@nctimes.com.

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