Hard rock provides haven for an endangered species

To save one of the world’s most endangered plants, biologists recently used jack hammers and diamond-cutting saws to excavate a shallow pool in the hard rock of a granite outcrop near Lake Oconee in Greene County.

The plant is the mat-forming quillwort, a primitive fern found worldwide at only eight sites in the Georgia piedmont. Each site is a rain-filled depression, or vernal pool, in a granite rock outcrop. (An outcrop is a visible exposure of bedrock at the Earth’s surface.)

Only a few of those pools — including some on Stone Mountain and Arabia Mountain in DeKalb County — are protected.

Biologists hope the 60-square-foot artificial pool in Greene County will provide new quillwort habitat. Clumps of quillworts were planted there a few weeks ago to see if they will thrive.

Last week, I went along with the biologists — Jimmy Rickard with the U.S. Fish and Wildlife Service and Kyla Cheynet with Plum Creek Timber Co. — to check on the quillworts.

The bright green plants with needle-like leaves were growing in about 3 inches of water. “They seem very happy,” Rickard said. With their branched roots, they anchor themselves in the thin soil at the pool’s bottom.

Rickard noted that this is the first artificial pool created for mat-forming quillworts, and the knowledge gained from it will help create new quillwort habitat elsewhere. (A similar effort is under way for a related endangered species, the black-spored quillwort.)

Plum Creek, which owns the Greene County outcrop, promises to protect the site and is partnering with state and federal biologists to create other habitats on company property.

The fragile pools in which the quillworts grow form naturally over thousands of years, Rickard explained. By excavating artificial pools, “we are speeding up nature,” he said.

Though never very abundant, the mat-forming quillwort has been decimated by rock quarries that mine granite for road-paving and building materials. Vandalism, off-road vehicle abuse, dumping, foot traffic, siltation and pollution also have taken a toll.

The quillworts planted in the artificial pool are descendants of plants removed a year ago from a natural pool threatened by a rock quarry. The rescued plants were taken to the State Botanical Garden in Athens, where botanists propagated them in a greenhouse. The state garden also will provide quillworts for other new habitats.

IN THE SKY: The moon will be last quarter on Thursday, said David Dundee, Tellus Science Museum astronomer. Mercury is low in the east just before sunrise. Jupiter is very low in the west at dusk. Saturn rises out of the east just after dark. Venus and Mars aren't easily seen right now.