A US federal agency is moving to protect a rare plant under the Endangered Species Act that is threatened by a proposed copper mine in southern Arizona, Kallanish reports.

The US Fish and Wildlife Service has designated Bartram’s stonecrop, a striking green-blue succulent whose population in the US numbers fewer than 5,000 plants, to be a threatened species under the ESA.

The stonecrop occurs in Pima, Cochise and Santa Cruz counties in southern Arizona. It was identified as a candidate for federal listing in 1980. The Center for Biological Diversity petitioned for the protection of the plant in 2010 and it sued the federal government in 2020. The plant is threatened by the proposed mine, livestock grazing, wildfires and drought triggered by climate change.

The stonecrop is not the only Arizona plant threatened by Hudbay Minerals’ now-stalled Rosemont copper mine in the Santa Rita Mountains south of Tucson, Arizona. The US Fish and Wildlife Service had earlier named a plant with yellow flowers, the beardless chinchwood, to be an endangered species.

The company has not commented on the two plants and the ESA. Under federal law, the company will have to prove to federal agencies that the mining operations will not harm the endangered plants before the project can proceed.

The company wants to build one of the largest copper mines in the United States with an open-pit mine that would be 1 mile across and up to 2,900 feet deep in the Coronado National Forest. It would operate for 19 years. Surroundings areas also would be used for mine tailings. The project would impact about 58,679 hectares.

That project has been halted by a federal judge who vacated the project’s final Record of Decision from the US Forest Service in July 2019. The company has appealed that decision to the 9th US Circuit Court of Appeals.