Butte County Meadowfoam

Limnanthes floccosa ssp. californica

Description

The false mermaid family contains plants characterized by alternate leaves, and three to five flowers that are regular and perfect. The Butte County meadowfoam is a densely hairy winter annual herb. The stems, which grow along the ground, are 1.2-9.8 in (3-25 cm) long. Appearing in late March through April, the flowers of this plant are white with dark yellow veins at the base of each of the five petals.

Habitat

Butte County meadowfoam is known to grow in seasonal wetlands, and has been reported to inhabit edges of deep vernal pools in undisturbed areas. It occurs in ephemeral drainages, vernal pool depressions in ephemeral drainages and occasionally around the edges of isolated vernal pools.

Vernal pools form in regions with Mediterranean climates where shallow depressions fill with water during fall and winter rains. Downward percolation is prevented by the presence of an impervious sub-surface layer, such as a clay bed, hardpan, or volcanic stratum. Plant species occurring in vernal pools are uniquely adapted to this "amphibious ecosystem" seasonal alteration of very wet and very dry conditions. Upland plants cannot tolerate the temporarily saturated to flooded soils of winter and spring while the seasonal drying makes the pool basins unsuitable for marsh or aquatic species requiring a permanent source of water.

A unique flora is represented within the vernal pool system, with species and genera which occur nowhere else.

Distribution

The Butte County meadowfoam is restricted to a narrow strip along the eastern flank of the Sacramento Valley from central Butte County to the northern portion of Chico in Tehama County, California.

Threats

The Butte County meadowfoam is primarily threatened by urban development in and around Chico in Butte County, California. Nine of the 11 populations occurring either partially or totally on private lands in the Chico area are threatened by urbanization. These sites have been zoned by the city of Chico for various types of urban uses, like residential, neighborhood commercial, or manufacturing-industrial park. Twelve of the remaining populations are vulnerable to urban development as well as airport maintenance activities.

Ninety percent of the population at the type locality was destroyed due to agricultural development (ag-land conversion).

One population outside the Chico area is threatened by the proposed construction of housing funded by U.S. Department of Housing and Urban Development.

This species may have agronomic value and has already been the focus of potential for agricultural use.

Livestock grazing has eliminated the meadow-foam from suitable habitat in the Chico area. This species seems tolerant to light to moderate to periodic heavy grazing pressure.

Conservation and Recovery

In 1989 a conservation plan was developed for the city of Chico that details various actions designed to conserve the Butte County meadowfoam in the Chico area.

Contacts

Regional Office of Endangered Species
U. S. Fish and Wildlife Service
Eastside Federal Complex
911 N.E. 11th Ave.
Portland, Oregon 97232
http://pacific.fws.gov/

Sacramento Fish and Wildlife Office
2800 Cottage Way, Room W-2605
Sacramento, California 98525-1846
Telephone: (916) 414-6600
Fax: (916) 460-4619

Reference

U.S. Fish and Wildlife. 8 June 1992. "Endangered and Threatened Wildlife and Plants; Determination of Endangered Status for the Plant Limnanthes floccosa ssp. californica (Butte County Meadowfoam)." Federal Register 57(110): 24192-24199.