|Magnoliopsida (Flowering Plants): Caprifoliaceae
Oval-leaved Viburnum (Viburnum ellipticum)
Potential Occurrence: Likely to Occur
Photos: Tom Engstrom
Photo: Dean Wm. Taylor
Species Description: The Oval-leaved Viburnum is slender, hairy and glandular with simple, deciduous, elliptic to round to cordate, coarsely dentate leaves that are 2 to 6 cm long (Hickman 1996). The inflorescence is a terminal, round to flat-topped, many flowered cyme with oblanceolate bracts and peduncles 1.5 to 4 cm long (Hickman 1996). The flower is saucer shaped with a white corolla, five stamens and a single chambered ovary with one ovule (Hickman 1996). The fruit is a 10 to 12 mm, elliptic, drupe with one 5 grooved seed (Hickman 1996).
Nomenclature: Viburnum ellipticum Hook. Caprifoliaceae (USDA 2010)
Synonyms: Viburnum ellipticum Hook var. macrocarpum Suksd. (USDA 2010)
Distribution: This species is found from Washington to California, where it occurs in the Northwest, the north and central Sierra Nevada Foothills and the San Francisco Bay Area (Hickman 1996).
Life History & Threats: The Oval-leaved Viburnum is a perennial shrub blooming from May to June and is threatened by habitat alteration (CNPS 2010).
Habitat & Habitat Associations:
Vegetation Types: Habitat for this is species chaparral dominated by mostly evergreen shrubs with thick, leathery leaves and stiff branches, lower montane coniferous forests dominated by open to dense stands of conifers and broadleaved trees in the understory, and cismontane woodland dominated by trees that are deciduous, evergreen or both with open canopies (CNPS 2010).
Topography and Microclimates: Sun to partial shade (Oregon State University 2002). Generally on north facing slopes (Hickman 1996).
Elevation: 215 to 1400 m (CNPS 2010) (The Study Area ranges from 230 to 710 m)
Species Associations: This species is known to associate with Oregon White Oak (Quercus garryana) and Poison Oak (Toxicodendron diversilobum) in Washington (Chappell 2006).
Conceptual Basis for GIS Model Development: Potential habitat in the Study Area was mapped as areas in:
chaparral (i.e. Northern Mixed chaparral)
coniferous forest (i.e. Redwood-Douglas fir mix (Sequoia sempervirens-Pseudotsuga menziesii) and Pacific Douglas fir (Pseudotsuga menziesii var.menziesii) vegetation types) with a multi-storied canopy
cismontane woodland (i.e., mixed, mixed montane or single dominant hardwoods with canopy cover <40%).
We additionally mapped best potential habitat in the areas identified above as:
Potential Occurrence in the Galbreath Wildlands Preserve:
Habitat: Habitat for Oval-leaved Viburnum in the Preserve is good quality and moderate in abundance. The best potential habitat for this species is coniferous forests and cismontane woodlands on north facing slopes. Chaparral, another vegetation type where this species can occur, does not occur within the Preserve. Potential habitat is patchily distributed throughout the Galbreath Wildlands Preserve. The largest contiguous portion of habitat is in the central part of the Preserve and is composed predominantly of cismontane woodlands. In this area, about half of lies on north facing slopes, providing best potential habitat for this species.
Documented Occurrences in the Galbreath Wildlands Preserve: Previous species list for the Galbreath Wildlands Preserve did not document this species (SSU Field Station and Nature Preserves 2010).
Nearest Occurrence to the Galbreath Wildlands Preserve: Oval-leaved Viburnum is known from areas north (3 occurrences in Humboldt County), south (15 occurrences in Sonoma County) and east (occurrences Lake, Glenn, and Tehama counties) of the Preserve (Calflora 2010). This species is known from 23 occurrences in Mendocino County (Calflora 2010). Distances among reported occurrences in Mendocino County can be as far as 12 miles (estimated from Calflora 2010 maps). The nearest occurrence is approximately 12 miles northeast of the Galbreath Wildlands Preserve in the Hopland quad in the Upper Russian River Watershed (Calflora 2010).
Summary: We anticipate this widespread species is “Likely to Occur” on the Preserve: habitat is good quality and abundant; the Preserve is bracketed by known occurrences to the north, south and east; and the species is documented to occur nearby (relative to distances observed among other documented occurrences).
Calflora. 2010. Information on California plants for education, research and conservation.. Accessed 2010 Jul 4.
California Native Plant Society (CNPS). 2010. Inventory of Rare and Endangered Plants. Online edition, v7-10b. . Accessed 2010 Jul 4.
Chappell CB. 2006. Quercus garryana/Viburnum ellipticum/Toxicodendron diversilobum. Upland plant associations of the Puget Trough ecoregion, Washington. Washington Department of Natural Resources Natural Heritage Program.
Engstrom T. 2006. Viburnum ellipticum. . Accessed Jul 4.
Hickman JC editor. 1996. The Jepson Manual Higher Plants of California. 3rd printing. London: University of California Press, Ltd. 475 p.
Oregon State University. 2010. Landscape Plants Images, Identification and Information. . Accessed 2010 Jul 4.
SSU Field Stations and Nature Preserves. 2010. Galbreath Wildlands Preserve Vascular Plant List. . Accessed 2010 Jun.
Taylor DW. 2006. Viburnum ellipticum. . Accessed Jul 20.
United States Department of Agriculture (USDA). 2010. PLANTS Profile. . Accessed 2010 Jul 20.
Species Account Description: Linden Schneider