Robbins' Cinquefoil

Potentilla robbinsiana

Description

Robbins' cinquefoil, Potentilla robbinsiana, also known as dwarf cinquefoil, is a low, almost stemless, perennial. It grows from a deep taproot and forms a dense rosette of compound leaves, formed from three leaflets. Mature plants are typically no more than 1.6 in (4 cm) in diameter. Flowering begins during the last week of May, and scattered yellow blooms may be found almost any time until October. Seeds mature in July and are dispersed by the wind. Seedlings never seem to sprout much more than a few inches from the parent plant.

From half to three-fourths of mature plants flower each year, producing an average of three flowers per plant. As many as 30 flowers have been observed from a single large plant.

Habitat

Robbins' cinquefoil grows in a treeless, nearly barren mountain habitat above 4,000 ft (1,220 m) in elevation, where the climate is harsh and competition from other plants is low. It roots in shallow, loamy sand terraces with a stony pavement-like surface that is subject to year-round frost heaving. The weakly calcareous soil is derived from fine-grained mica schist. The stony surface layer protects the soil from blowing or washing away in high winds or severe storms. Fine soil particles collect among the stones and become nurseries for newly germinated cinquefoil.

Distribution

This cinquefoil is endemic to the White Mountains of New Hampshire and Vermont. It was known historically from four sites. The two existing natural populations of this New Hampshire plant have been monitored since the species was listed in 1980, and are fully protected through cooperative efforts by the U. S. Fish and Wildlife Service (FWS), U. S. Forest Service (USFS), and Appalachian Mountain Club (AMC). Only one population of Robbins' cinquefoil, found on a 2-acre (0.8-hectare) patch at Monroe Flats is considered stable and viable. In addition, four transplanted colonies are being monitored on Forest Service lands.

In 1980 the population consisted of 3,700 established plants, plus an additional 770 newly germinated seedlings at two different sites. In 1985, only about 1,600 plants survived in an area of less than 2.5 acres (1 hectare). Current populations are estimated at about 1,700 adults.

Threats

Hikers and collectors are principally responsible for the two of the four historic populations of Robbins' cinquefoil. Decline of the remaining populations was caused by hikers along the Appalachian Trail. The fragile habitat along the trail is open to hikers who stray from the established path, but it is extremely vulnerable to disturbance. Hikers dislodge the close-fitting "pavement" stones of the surface, causing soil from around the plants to wash or blow away. When roots are thus exposed, plants die. Once disturbed, the cinquefoil is very slow to recover. Because of the harsh extremes of the climate, seedling mortality is high, and the population is subject to a large natural fluctuation of numbers.

Conservation and Recovery

In 1981, the FWS, the USFS, and the AMC began a joint public education program encouraging hikers to "stay on the trail" to protect the cinquefoil and other alpine plants. In 1983, the Crawford Path was diverted around the population site, essentially closing the area to public access.

The Robbins' Cinquefoil Recovery Plan was completed in 1985 and outlines three major objectives: to protect the existing population in its entirety; to encourage natural expansion; and to establish four new self-sustaining populations within the plant's historic range. Critical Habitat was designated to include the Monroe Flats area, a strip of land 4,000 ft (1,220 m) long by 450 ft (137 m) wide.

Research into the plant's biology has been conducted by the FWS in conjunction with the AMC and the USFS with a view toward transplantation efforts. Because of the plant's rarity and unusual reproductive strategy, the recovery plan called for an extensive species viability analysis, population dynamics studies, and refinement of propagation and transplant techniques. These studies are now complete, and transplanting expeditions have become an annual event for the recovery partners.

Such cooperation has engendered optimism for the survival of Robbins' cinquefoil. Public education, an updated recovery plan, a permanent educational display for hikers, and the rerouting of a hiking trail are having positive effects.

Contact

U. S. Fish and Wildlife Service
Regional Office, Division of Endangered Species
300 Westgate Center Dr.
Hadley, Massachusetts 01035-9589
Telephone: (413) 253-8200 Fax: (413) 253-8308
http://northeast.fws.gov/

References

Graber, R. E. 1980. "The Life History and Ecology of Potentilla robbinsiana." Rhodora 2: 131-140.

Storks, I. M., and G. E. Crow. 1979. "Endangered, Threatened, and Rare Plants of the White Mountain National Forest, New Hampshire." University of New Hampshire Department of Botany and Plant Pathology, Durham, New Hampshire.

U. S. Fish and Wildlife Service. 1983. "The Robbins' Cinquefoil Recovery Plan." U. S. Fish and Wildlife Service, Newton Corner, Massachusetts.