Newhall Land and Farming Co., developers of the proposed Newhall Ranch project in the Santa Clarita Valley, has agreed to preserve an additional 1,500 acres for a flower that grows there and only one other place.

The company, owned by Five Point Holdings of Aliso Viejo, and the U.S. Fish and Wildlife Service agreed on a Candidate Conservation Agreement for Chorizanthe parryi var. Fernandina, known as the San Fernando Valley spineflower.

Under the agreement, Newhall Land will conserve nearly 1,500 acres for the flower and carry out additional conservation efforts there and elsewhere to help reduce and eliminate threats to the flower. The company will help to increase its numbers by protecting introduction sites, the federal agency said. Those sites will take place on at least 10 acres within the conserved area, and two new populations will result, the agency said.

The federal agency had proposed adding the flower to the List of Endangered and Threatened Plants about a year ago with a 60-day comment period. It extended that period in July for six months, and the recent extension adds another 30 days to the process.

The spineflower is low-growing herbaceous annual plant that flowers usually between April and June and is pollinated by ants and honeybees. It is found in the Newhall Ranch area as well as in the Upper Las Virgenes Open Space Preserve. It was thought to be extinct until rediscovered in Ventura County in 1999, according to the Fish and Wildlife Service.

As a result of the agreement, the federal agency is reopening the public comment period on whether or not to designate the flower as a threatened species. Members of the public have 30 days – till Dec. 13 – to express their opinions to the federal agency on the issue.

Newhall Ranch has proposed building 21,500 homes, 11.5 million square feet of commercial space, seven schools, 275 acres of parks and 60 miles of trails on 15,000 acres in the northern L.A. County area.

In September, Five Point settled with several environmental groups opposing the project and agreed to shrink the project’s size and establish an archeological and conservation fund for threatened and endangered wildlife in the Santa Clarita River’s ecosystem.