Magnoliopsida (Flowering Plants): Convolvulaceae

Three Fingered Morning Glory (Calystegia collina ssp. tridactylosa)

Potential Occurrence: Unlikely to Occur

Status:

Federal: none

State: none

CNPS: 1B.2

Other: none

Species Description: The Three Fingered Morning Glory is densely tomentose and decumbent with long brownish hairs that is not or weakly climbing (Hickman 1996). The leaf is generally 3 cm at mid rib with 2 distinct basal lobes and a barley wavy margin (Hickman 1996). The inflorescence is solitary with linear elliptic to lanceolate bracts not fully enclosing the calyx (Hickman 1996). The flower is showy with tomentose sepals and a glabrous white corolla (Hickman 1996). The fruit is a spheric capsule with about 4 seeds (Hickman 1996).

Nomenclature: Calystegiacollina (Greene) Brummitt ssp. tridactylosa (Eastw.) BrummittConvolvulaceae (USDA 2010)

Synonyms:C. tridactylosa, (Hickman 1996)

Distribution: This species occurs in the North Coast Range particularly in Mendocino and Lake counties (Hickman 1996).

Life History & Threats: The Three Fingered Morning Glory is a rhizomatous perennial herb (CNPS 2010; Hickman 1996). It is a broad serpentine endemic with 85 to 94% of occurrences being on ultramafics (Calflora 2010). It is potentially threatened by geothermal energy development (CNPS 2010).

Habitat & Habitat Associations:

Vegetation Types: Habitat for this species is chaparral dominated by mostly evergreen shrubs with thick, leathery leaves and stiff branches, cismontane woodland dominated by trees that are deciduous, evergreen or both with open canopies, and oak-pine woodlands (CNPS 2010; Hickman 1996).

Topography and Microclimates: Open grassy or rocky areas (CNPS 2010; Hickman 1996)

Elevation: 0 to 600 m (CNPS 2010) (The Study Area ranges from 200 to 740 m).

Geology and Soils: Rocky, gravelly, or serpentinite (CNPS 2010; Hickman 1996). Heavy clay soil (Janeway 2002).

Species Associations: Found with Kellogg’s yampah (Perideria kelloggii), hayfield tarweed (Hemizonia congesta), and aster species (Lessingia sp.) (Janeway 2002).

Conceptual Basis for GIS Model Development: Potential habitat in the Study Area was mapped as areas:

  • below 630 m (includes a 30 m buffer on known elevational occurrences of this species
  • chaparral (including scrub oak) or woodlands (i.e. mixed or single dominant hardwoods with a canopy cover 40%)

Best potential habitat was mapped as areas in the above vegetation types with:

  • rocky (i.e., gravelly (gravelly loam, very gravelly loam, cobbly loam, very cobbly loam, or alluvium) or clay (i.e., clay loam) soils

Potential Occurrence in the Galbreath Wildlands Preserve:

Habitat:Best potential habitat in the Preserve for Three Fingered Morning Glory is woodlands with rocky or clay soils. This habitat type is present in the center and eastern portion of the Preserve.

Habitat quality is poor. While rocky and clay soils are abundant in woodland areasof the Preserve, this habitat type is not a common type for this species. Three Fingered Morning Glory occurrence is highly correlated with ultramafic soils, such as serpentine. To verify the lack of serpentine soils reported in the Preserve in GIS information, we identified all areas (11 sites) of exposed rocky soils from high-resolution satellite imagery. During site visits to these areas, the only serpentine found were rocks exposed by road maintenance activity at a waterbar. In addition, chaparral, a common habitat type for this species, also does not occur in the Preserve.

Nearest Occurrence:

Documented Occurrences in the Galbreath Wildlands Preserve: A previous site visit of the GalbreathWildlands Preserve did not find this species (SSU Field Station and Nature Preserves 2010)

Nearest Occurrence to the Galbreath Wildlands Preserve: All reported occurrences for this species are to the east of the Preserve in Mendocino, Lake and Colusa counties (Calflora 2010). In Mendocino County, the species is known from 10 occurrences in four adjacent USGS quads in the northcentralregion of the County. The nearest occurrence to the Preserve is 50 miles to the northeast in the Upper Eel River watershed (Calflora 2010).

Summary:Three Fingered Morning Glory is “Unlikely to Occur” in the Preserve because habitat quality is poor, occurrence at the Preserve would constitute a western range extension for the species, and the species has not been documented to occur nearby (relative to distances observed among other documented occurrences).

References

Bureau of Land Management, Arcata Field Office (BLM). 2003. Calystegia collina ssp. tridactylosa; Coast Range False Bindweed. < Accessed 2010 Oct 25.

Calflora. 2010. Information on California plants for education, research and conservation.< Accessed 2010 Jun 29.

California Native Plant Society (CNPS). 2010. Inventory of Rare and Endangered Plants. Online edition, v7-10b. < Accessed 2010 Jun 29.

Hickman JC editor. 1996. The Jepson Manual Higher Plants of California. 3rded.. London: University of California Press, Ltd. 518 p.

Janeway LP. 2002. Consortium of California Herbaria. < Accessed 2010 Jun 29.

SSU Field Stations and Nature Preserves. 2010. Galbreath Wildlands Preserve Vascular Plant List. < Accessed 2010 Jun.

United States Department of Agriculture (USDA). 2010. PLANTS Profile. < Accessed 2010 Oct 25.

Species Account Description:Linden Schneider