U.S. Seeks to Come to the Aid of 6 Rare Plants : Santa Monica Mountains: A federal agency has a year to formally decide whether the species deserve to be listed as endangered or threatened.

Six rare plants that grow wild in the Santa Monica Mountains have been proposed by the U.S. Fish and Wildlife Service for the nation’s endangered and threatened species lists.

Two of the plants are the subject of a lawsuit that the Santa Monica Mountains Conservancy filed against the Federal Deposit Insurance Corp. in July. The conservancy wants to block the proposed sale of nearly 500 acres around Westlake Reservoir to the Baldwin Co., an Irvine developer that wants to build luxury houses on land where the rare wildflowers grow.

One of the two wildflowers is the Lyon’s pentachaeta, an aster with wispy yellow flowers that grows in grasslands and is native to the Santa Monica Mountains. The government wants to add it to the endangered species list. The other is a rare succulent known as the Santa Monica Mountains dudleya, which is being considered for threatened status in the agency’s proposal, which was formally issued Nov. 30.

The government agency has a year to formally decide whether the plants deserve endangered or threatened species protection. Public input will be accepted through Jan. 29.

Endangered status does not prevent landowners from building over listed plants. But developers must formally consult with the federal wildlife agency and document the threat, after which they are encouraged to develop scientifically sound ways to protect the plant. Threatened status affords lesser protections.

Also proposed for protection as an endangered species is a rare pink-flowered herb known as Braunton’s milk vetch, which is imperiled in two Orange County canyons, Ventura County’s Simi Hills and in a Los Angeles County portion of the Santa Monica Mountains, said Tim Thomas, a botanist in the wildlife service’s Ventura field office. Three other species of dudleyas plants are being proposed as threatened species, which means they are in less danger of extinction than endangered species.

Nevertheless, Thomas and others said, all of the six plants are being threatened more than ever because of pending development projects--especially the project surrounding Westlake Reservoir--that could further destroy their natural habitat.

“They’ve never been common in the first place, but they’ve been less common because of elimination and destruction of their habitat,” Thomas said. “These species don’t exist in vacuums. They don’t live in zoos.”

The pentachaeta, for instance, currently grows in fewer than 20 sites in a 20-mile stretch of the Santa Monica Mountains and western Simi Hills, according to federal reports. David L. Maghey, state president of the California Native Plant Society, has written in opposition to the land sale, saying the Westlake Village property is the best remaining concentration of the Lyon’s pentachaeta plant in the entire mountain range.

The pentachaeta, the Santa Monica Mountains dudleya and another of the proposed plants, the marcescent dudleya, are “canyon dwellers” that flourish in center portions of the Santa Monicas, including unincorporated areas of Los Angeles County, Westlake Village, Agoura Hills, Santa Ynez Canyon and the Topanga area, Thomas said. Two of the others proposed for the threatened list are also dudleya varieties: the Verity’s dudleya and Conejo dudleya, which are found mostly in the western portion of the mountain range in Ventura County, Thomas said.

Federal officials are reluctant to give the exact locations of the plants for fear they may be tampered with by those with pending development projects. “Oftentimes, developers have this nasty habit of eliminating the plants before they can be listed. It’s a real problem,” Thomas said. “We have to make sure that that doesn’t take place.”

Thomas said bulldozer operators in the employ of the Calleguas Municipal Water District crushed a marked population of pentachaeta last week near the Ronald Reagan Presidential Library just outside the city of Simi Valley.

The listings of the six plants were the direct result of a lawsuit filed by California Native Plant Society against the federal wildlife service, alleging that the agency had taken too long to protect dozens of species of threatened plants. The settlement of that case created a timetable for federal officials to take action to protect the plants. The six plants proposed Nov. 30 are the first to be acted upon, said Peter Ireland, assistant executive officer for the Mountains Recreation Conservation Area, an arm of the Santa Monica Mountains Conservancy.

By adding the plants to the list of proposed endangered species, Ireland said, the Fish and Wildlife Service has helped environmentalists in their effort to get the FDIC to sell the Westlake land to them or another environmental group so the species can be better protected.

“These two species are critical to us,” Ireland said. “And the timing is very important--it elevates the status of these species, certainly with respect to our litigation.”

Ireland said even the act of placing the plants on the list for consideration as endangered species will require the FDIC to engage in consultation meetings with the wildlife service before it can sell the land to the Baldwin Co., which wants to build 330 luxury houses by the lake’s rugged shore. The proposal to make the Lyon’s pentachaeta an endangered species could even trigger a forced redesign of the project, Ireland said.

Baldwin Co. officials were unavailable for comment, but have said they plan to press ahead with their efforts to buy the property for an undisclosed sum of money.

But the Santa Monica Mountains Conservancy, and some allies, continue to fight Baldwin for control of the property. U.S. Rep. Anthony C. Beilenson (D-Los Angeles) has asked the FDIC to delay the sale because the land is one of few habitats for both the pentachaeta and the Santa Monica Mountains dudleya. Conservancy officials have argued that the FDIC should sell the property to them, because federal guidelines require the agency to offer land on which endangered species are found to groups dedicated to protecting wildlife and preserving open space.

However, even if the wildflower becomes protected as a member of the endangered species list, the FDIC has argued that it would not be required to abide by the regulations because it is holding the land as a receiver of property of a failed savings and loan, and not as a federal agency. The conservancy has contended that the FDIC is not exempt from complying with the Endangered Species Act, Ireland said.

Environmentalists say the move to place the six plant species on the endangered or threatened lists could signal the beginning of a wave of listings in Southern and central California.

The agency has proposed adding at least 16 other Southern California plants to the national list, which means final decisions are less than a year away. Another 70 animals and plants--including three other birds in Orange County--are not as far along in the process, but are still classified as top candidates, with some facing court-ordered deadlines.

Times staff writer Marla Cone contributed to this article.