A tenacious little plant with a bright yellow blossom may be one of many canaries in the coal mine of climate change. And it was the subject of a determined search last week on the misty cliff faces of Grandfather Mountain and Elk Knob.
The spreading avens (Geum radiatum) has clung to mountain rocks since before the last ice age but may be disappearing. There are thought to be fewer than a dozen populations left in the world, and it’s one of those endangered species you hear so much about. That’s why biologists from the state parks system, the National Parks Service and other agencies hunted the plant at the two state parks and on adjacent property of the Grandfather Mountain Stewardship Foundation last week.
The two-day search resembled one for a lost hiker, with scientists rappelling over cliff edges and scrambling through heavy brush on steep slopes to map and measure plots of the plant and examine evidence of flowering and seeds.
Spreading avens is among a tribe of plants that live in rare biospheres at high Appalachian altitudes, often described by science writers as biological islands in the mountain landscape. Assuming the planet is indeed warming, these islands may grow smaller or disappear altogether as an ocean of warmer temperatures gradually rises up the slopes.
So far, the known spreading avens populations in the state parks and elsewhere seem to be holding their own but there’s not much evidence they’re “spreading” as their common name implies, according to Chris Ulrey of the National Park Service.
The difficulty of this survey was enough to prompt several agencies to combine forces, said Marshall Ellis, a state parks system biologist. Results are sent to the U.S. Fish and Wildlife Service, the official keeper of the books on endangered species, he said. “It’s also an effort to use the same protocol and methods so we’re all counting oranges and not oranges and apples.”
Frequently, one of the reasons for creating a state park is the notion that a site is a haven for rare species. The biologists with the state parks system and their colleagues are the ones that must make the case for those claims. It’s vital for conservation and the state parks to know what’s growing and where.
(Enjoy our gallery of photos from the spreading avens survey. Click on any image to begin.)