Experts Call Outlook Grim for County’s Rare Plant Life
These are unhappy days for San Diego County’s rare plants and trees.
Development is putting more plant species in danger of extinction here than anywhere in the state, according to the California Native Plant Society.
Only San Bernardino County has more kinds of rare, threatened or endangered plants--187, compared with San Diego County’s 173. But naturalists say many of the San Diego plants grow in easily developed areas, while a high percentage of San Bernardino’s thrive in secluded spots.
At the same time, they say, getting such species on state and federal endangered lists is becoming more difficult.
“It is not a pretty picture as far as the future of plants in San Diego,” said Geoffrey Levin, curator of botany at San Diego’s Natural History Museum.
San Diego “enjoys such a variety of environments, and it’s a unique habitat for plants,” according to David Klinger, a spokesman at the U.S. Fish and Wildlife Service’s Pacific Region headquarters in Portland, Ore. San Diego’s diverse geography “is set against a backdrop of incessant development that is just crowding many of these species out,” he said.
Naturalists say dozens--if not hundreds--of plants in the county need protection.
Yet just three native plants--the San Diego mesa mint, which is endemic, or found only in San Diego county; the salt marsh bird’s beak, and the slender-horned spine flower--have been placed on the federal endangered list. Interestingly, federal officials learned only recently that the spine flower, which has been spotted in San Bernardino, Orange and Los Angeles counties, grows in San Diego.
Federal officials are considering the addition of three other native plants, but no decision has been reached in the nearly two years since the status for two of those plants was proposed on a fast-track “emergency” basis.
The state of California’s rare, threatened and endangered plant list includes 26 species that grow in San Diego. But a state commission recently refused to list a tree whose only home in the United States is found in a few areas within San Diego and Orange counties.
California first listed rare, threatened and endangered plants in 1978. In 1979, 124 species were listed; the state now lists 188, and the plant society says the number should be higher.
The state and federal lists, which can stop development that might destroy the plants, are “the only mechanism we have to keep these plants safe,” according to Joan Stewart, a member and past president of the plant society’s San Diego chapter.
But the regulatory gears move slowly:
* It has been nearly two years since federal regulators, acting on an “emergency basis,” suggested that the Otay Mesa mint and California Orcutt’s grass be added to the federal list. Washington-based lawyers for U.S. Fish and Wildlife recently ordered their West Coast counterparts to produce “better substantiation” that the plants need protection.
* The state Fish and Game Commission in October refused to list the Tecate cypress, which grows at only three locations in San Diego County and one in Orange County. That decision ran counter to unanimous agreement among independent naturalists and the botanists at the state Department of Fish and Game, who recommended that the tree be listed.
Those kinds of regulatory responses lead naturalists to argue that listed plants represent “just the tip of the iceberg,” said Mitchel Beauchamp, a local botanist who wrote the definitive catalogue of San Diego’s plant life.
Beauchamp, who in 1978 became the only San Diegan to successfully lobby federal regulators to include an endemic plant on the endangered list, argued that the state and federal lists include just 10% of the plant species in the county that need protection.
While it took just months to win protection for the San Diego mesa mint in 1978, Beauchamp says it would now take “years” for a botanist to navigate the increasingly complex regulator maze that leads to a plant being listed.
“The listing process is terribly cumbersome,” said Stewart, the past local president of the California Native Plant Society.
To many botanists and biologists, the federal and state listing processes have become highly political exercises that are dominated by special interests--in many cases, land developers--who use their clout to prevent controversial additions to the lists.
“Our goal is to maintain the status quo,” acknowledged Klinger of Fish and Wildlife. “We’re never going to restore what once was. It’s a tough assignment, which I’ve referred to as ‘our Vietnam.’ We’re fighting a rear-guard action . . . with more and more species being destroyed.”
Naturalists say that only the California Native Plant Society’s “Rare and Endangered Vascular Plants” listing takes a true measure of plants that, without help, face a bleak future.
San Diego’s awesome array of plant life is made possible by the county’s wide and unusual array of coastal, inland valley, mountain and desert habitats. The county is also home to species found both along the northern edge of Baja California and in the southern reaches of Northern California.
In contrast, the plant society lists just 88 species in Los Angeles and 42 in Orange County, both of which lack San Diego’s geographic diversity.
San Diegans might be familiar with the wildflowers that bloom annually in the desert and the magnificent Torrey pines that dominate the oceanfront reserve, but relatively few know about the county’s other plants.
Some of the species--the Otay tarplant, Borrego bedstraw and the Mexican flannelbush--have names that only Mother Nature could love. One endangered plant--the short-leaved liveforever--has a decidedly unprophetic name.
For the most part, San Diego’s native plants are not “warm or fuzzy, or like a pretty bird” that easily captures the public’s imagination, according to Stewart, who is also a research biologist at UC San Diego’s Scripps Institution of Oceanography.
Oliver Ryder, a geneticist at the San Diego Zoo, said the county’s youth “are not being shown, are not being taught” about San Diego’s plant and animal diversity. Students regularly tour the San Diego Zoo and its wealth of “charismatic mega-vertebrates . . . but how many kids, or adults of any age, for that matter, have ever seen a vernal pool?” Ryder asked.
Vernal pools, the seasonal ponds that once dotted mesas throughout the county in rainy seasons, are perhaps the best example of natural habitats that were destroyed as developers made way for houses, shopping centers and roads.
The pools once flourished around the county, including on College Mesa, now home to San Diego State University. But vernal pools have been largely destroyed because they exist only in flat areas, which are highly prized by developers.
It is in the county’s remaining vernal pools that the San Diego mesa mint, the only endemic plant on the federal government’s endangered plant list, thrives. The plant now grows only in scattered locations, including some relatively pristine land at Miramar Naval Air Station.
During the dry season, the mint appears brown, scrawny and lifeless. But it blossoms as winter and spring rains fill the delicate pools that are chock-full of life. With sufficient rain, the mesa mint is transformed into a delicate beauty with blue blossoms and a mint smell.
Similarly, the Otay Mesa mint, a close relative that is clinging to life in the Otay Mesa area, is headed toward possible extinction as its habitat is destroyed through increased recreational, commercial, residential and farming uses, according to Ellen Bauder, an adjunct professor at SDSU.
The Otay Mesa mint is one of the three native plants being considered for inclusion on the federal endangered list. But, as Levin noted, most biologists believe that, “by the time a threatened plant is listed by the federal government, it’s probably going to be extinct.”
Life has always been tough for the mesa mint family. Botanists theorize that each mesa in San Diego County might at one time have served as home to a distinct branch of the family.
In 1979, when given a choice between tomato plants and the San Diego mesa mint, county supervisors embraced the cash crop and abandoned proposed legislation that would have forced farmers to plow around the pools that served as home to the now-endangered plants.
In 1987, state and federal regulators chastised the city of San Diego for failing to spend $500,000 in specially earmarked preservation funds on lands that contained some of the region’s few remaining vernal pools.
“We’ve had a very consistent response in recent years from the city,” said Susan Cochrane, who monitors threatened and endangered plants and animals for Fish and Game in Sacramento. “They’ve done absolutely nothing” to preserve vernal pools, she said.
Actually, the city recently acquired a tract that houses several vernal pools. Crews will soon fence the area to prevent vehicles from damaging the fragile pools.
But Bauder, the SDSU adjunct professor, questioned the wisdom of the city program because the fund grew from “mitigation fees” paid by developers who bulldozed such pools elsewhere in the city.
By her count, the city’s acquisition fund represents nearly 800 vernal pools that have been destroyed by developers. “No one can call that mitigation,” Bauder said of the tract acquisition.
“The problem is that vernal pools are very sensitive and they only occur on flat mesa-top areas,” said Tom Huffman, a senior planner with the city of San Diego. “Unfortunately, that’s the most prized area for development. . . . It’s a lot easier to protect steep canyon slopes.”
And, once vernal pools are preserved, it is difficult to protect them because just “one person walking back and forth” can severely damage the sensitive pools, said Paul Zedler, an SDSU biology professor who has studied vernal pools and the mesa mint.
“If you went out there (in the dry season), vernal pools aren’t going to be very impressive,” he said. “It would look like dried mud.”
But, in the winter and spring, the shallow pools, with diameters of up to 100 feet, fill up, sprouting “a whole little ecosystem, with animals and plants that are all adapted to life in the vernal pools,” Zedler said. “It would be like walking in soup.”
“No doubt we’re down to a fraction of what the population used to be,” he said. Naturalists know that vernal pools used to be spread all across the county. In the 1930s, a Hoover High School professor wrote a report that catalogued a “huge” collection of pools in what is now Linda Vista, Zedler said.
“I can’t tell you the exact status, but if a pool is on private land that’s slated for development, then it’s a goner,” he said. “
To naturalists, the plight of San Diego’s vernal pools underscores the dramatic failure of the current environmental protection scheme.
“You can save individual rare species by putting up a white picket fence around them,” Stewart said. But the fence won’t ensure that the entire habitat is saved.
The “current strategy of completing environmental impact reports isn’t working,” Stewart said. “It’s keeping a lot of botanists employed, but we’re not conserving the resources.”
RARE PLANTS OF SAN DIEGO COUNTY
1. Salt Marsh Bird’s Beak (Cordylanthus maritimus) grows in the Tijuana River Estuary, as well as parts of Chula Vista and Imperial Beach. It grows only in saltwater marshes.
2. Dunn’s Mariposa (Calochortus dunnii) grows on Otay Mountain and in parts of the Cuyamaca Mountains near Julian and Descanso.
3. Parish’s Slender Meadowform (Limnanthes gracelis) has white petals that extend from a yellowish base. It grows in wet areas, including Palomar Mountain and the Cuyamaca Mountains. 4. San Diego Mesa Mint (Pogogyne Abramsii) was the first endemic plant placed on the federal list of endangered plant species. The mint used to grow on top of mesas throughout San Diego, but now is found only at a few locations, including Miramar Naval Air Station. The plants, which bloom in the wet season, have a rosy-purple coloring.
5. Coastal Dunes Milk-Vetch (Astragalus tener), which grows along the Santa Margarita River and the Silver Strand, grows in alkaline areas. Some milk-vetch plants have purplish-blue pods while others are whitish.
The information was taken from R. Mitchel Beauchamp’s “Flora of San Diego County” and LeRoy Abram’s “Illustrated Fauna of the Pacific States.” Illustrations were based on drawings in Abram’s book.
