California Taraxacum

Taraxacum californicum

Description

California taraxacum, Taraxacum californicum, a member of the aster family (Asteraceae or Compositae), is a thick-rooted perennial herb. The leaves, arranged in basal rosettes, 2-8 in (5-20 cm) high, are light green, oblanceolate, nearly entire to sinuate-dentate (wavy toothed) from 2-5 in (5-13 cm) long and 0.4-1.2 in (1-3 cm) wide. The light yellow flowers are clustered in heads on leafless stalks. The outer phyllaries (bracts of the inflorescence) are erect, lance-ovate and 0.2 to 0.3 in (5-7.6 mm) long while the inner phyllaries are lance-linear, and 0.5-0.6 in (1-1.5 cm) long. Plants flower from May to August. California taraxacum is readily distinguished from other exotic members of this genus within its range by its lighter green foliage, sub-entire leaves, stocky cylindrical heads with truncate bases, erect phyllaries, paler yellow flowers, and small fruits.

Habitat

California taraxacum occurs in moist meadow habitats in the San Bernardino Mountains at elevations from 6,700-9,000 ft (2,042-2,743 m) and is often associated with Poa atropurpurea. These taxa are restricted to the relatively open edges apart from more mesic plants such as P. pratensis, Carex spp. or Juncus spp. The perimeter of such meadows often intergrades with sagebrush scrub dominated by sagebrush or pine forest.

Distribution

California taraxacum is known to occur on federal, state, municipal, and private lands. About 20 occurrences of the species are currently known, with population sizes ranging from 200 to 300 individuals. About half of these occurrences are located within, or adjacent to, urbanized areas such as Big Bear City, Big Bear Lake Village, and Sugarloaf in San Bernardino County, California. All of these occurrences are threatened by urbanization.

Threats

This species is imperiled by a variety of activities that result in habitat modification, destruction, degradation, and fragmentation. These activities include urbanization, off-road vehicle activity, alteration of hydrological conditions, and vandalism.

Conservation and Recovery

About half of the 20 known populations of the California taraxacum are located in or adjacent to urbanized areas, such as Big Bear City, Big Bear Lake Village, and Sugarloaf. All of these critical habitats are threatened by urbanization and associated disturbances, such as road building. The largest populations on private land should be protected. This could be done by acquiring the critical habitat and designating ecological reserves, or by negotiating conservation easements with the landowners. Populations occurring on land already owned by the state or federal government should be protected against any threatening disturbances. The populations of the California taraxacum should be monitored, and research conducted into its biology and habitat needs.

Contacts

U. S. Fish and Wildlife Service
Regional Office, Division of Endangered Species
Eastside Federal Complex
911 N. E. 11th Ave.
Portland, Oregon 97232-4181
Telephone: (503) 231-6121
http://pacific.fws.gov/

U. S. Fish and Wildlife Service
Carlsbad Field Office
2730 Loker Avenue West
Carlsbad, California 92008-6603
Telephone: (760) 431-9440
Fax: (760) 431-9624

Reference

U. S. Fish and Wildlife Service. 14 September 1998. "Endangered and Threatened Wildlife and Plants: Final Rule to Determine Endangered or Threatened Status for Six Plants from the Mountains of Southern California." Federal Register 63 (177): 49006-49022.