San Francisco Peaks Groundsel

Senecio franciscanus

Description

San Francisco Peaks groundsel, Senecio franciscanus, is a dwarf perennial, growing up to 4 in (10 cm) tall. Leaves are deeply lobed and much reduced in size toward the top of the plant. Yellow-rayed flowers, about 0.4 in (1 cm) across, occur singly or in clusters of up to six per flower head. The plant reproduces vegetatively through its spreading rhizome but occasionally sets seed. Flowers bloom from August to early September, and fruits mature in mid-September. The plant goes into winter dormancy by early October.

Habitat

At higher elevations (above 10,900 ft; 3,322.2 m), the montane spruce-fir forests of the Southwest give way to an alpine tundra that is characterized by a sparse, dwarfed vegetation. In this austere alpine habitat, San Francisco Peaks groundsel grows on loose talus slopes that form at the base of rocky cliffs. It is adapted to natural soil movement due to frost and gravity of the steep slopes of the Peaks. Growing in exposed, sunny situations, the Peaks groundsel form mature colonies near rocks, where they are better protected from the elements. Soil moisture is the most important factor controlling the growth and distribution; wind action is also important because it influences moisture patterns, producing abrasion of plants, reducing temperature, and influencing pollination. Other species associated with this alpine tundra are bristlecone pine, Engelmann spruce, avens, alumroot, and gooseberry.

Distribution

The plant is considered endemic to the San Francisco Peaks, which are situated north of Flagstaff in Coconino County, Arizona.

This groundsel is common along a narrow saddle that connects Agassiz and Humphreys Peaks, a few miles from the highest point in the state. The site occurs within the Coconino National Forest. Habitat elevation is between 11,000-12,200 ft (3,350-3,750 m).

The San Francisco Peaks groundsel populations have been stabilized as a result of the recovery efforts and appear to be in a healthy reproductive state. The species occurs in at least a quarter of the 1,200-acre (485.6-hectare) alpine area; at the time of publication of the recovery plan, the population was thought to be at least 100,000 individuals.

Threats

Most of the naturally restricted habitat of San Francisco Peaks groundsel remains relatively pristine, but the narrow distribution of the plant makes it vulnerable to human disturbance. A portion of the habitat was destroyed when the Snow Bowl ski lift was constructed on Mount Agassiz, but more damage has been caused by people attracted to the scenic area in summer. Increasing numbers of hikers have used the ski lift as a stepping-off point for excursions to the mountain summits. These hikers have worn numerous parallel tracks along the western face of the slope to the crest of Humphreys Peak and have inadvertently trampled plants along existing hiking trails. Climbers easily dislodge the talus slopes, destroying plants and preventing establishment of new plants.

Conservation and Recovery

When San Francisco Peaks groundsel was listed as threatened in 1983, critical habitat was designated to include the summits of Agassiz and Humphreys Peaks and the surrounding slopes, taking in the plant's entire known range. The designated area provides a buffer for existing plants and space for populations to expand.

The Forest Service is working to keep hikers off fragile talus slopes. In 1984 a hiking trail was constructed from the upper Snow Bowl Lodge to the saddle north of Agassiz Peak and the Westherford trail down the back side of Agassiz. Trailed routes were selected from aerial photographs so as to bypass endangered species' habitats. The old trail was closed with a sign explaining the reason.

A public education program informs visitors of the importance of preserving alpine tundra habitat. If disturbance can be minimized, the groundsel will continue to thrive in its narrow mountain niche.

Contact

U. S. Fish and Wildlife Service
Regional Office, Division of Endangered Species
P. O. Box 1306
Albuquerque, New Mexico 87103-1306
Telephone: (505) 248-6911
Fax: (505) 248-6915
http://southwest.fws.gov/

References

Phillips, A. M., and E. Peterson. 1980. "Status Report: Senecio franciscanus." Office of Endangered Species, U. S. Fish and Wildlife Service, Albuquerque.

U. S. Fish and Wildlife Service. 1983. "Final Rule to Determine Senecio franciscanus (San Francisco Peaks Groundsel) to Be a Threatened Species and Determination of Its Critical Habitat." Federal Register 48:52743-52747.

U. S. Fish and Wildlife Service. 1986. "San Francisco Peaks Groundsel Recovery Plan, Technical/ Agency Draft." Endangered Species Office, Albuquerque.

U. S. Fish and Wildlife Service. 1987. "Endangered and Threatened Species of Arizona and New Mexico (with 1988 Addendum)." U. S. Fish and Wildlife Service, Albuquerque.