Eriogonum nudum var. auriculatum

(Bentham) J. P. Tracy ex Jepson

Fl. Calif. 1: 420. 1914.

Common names: Ear-shaped wild buckwheat
Endemic
Basionym: Eriogonum auriculatum Bentham Trans. Linn. Soc. London 17: 412. 1836
Synonyms: Eriogonum latifolium var. alternans S. Stokes Eriogonum latifolium subsp. auriculatum (Bentham) S. Stokes
Treatment appears in FNA Volume 5. Treatment on page 312. Mentioned on page 309, 310, 313.

Plants 5–15(–20) dm. Aerial flowering stems occasionally fistulose, 2–5(–10) dm, glabrous. Leaves sheathing; blade 3–7 × 2–4 cm, tomentose abaxially, subglabrous or glabrous adaxially, margins strongly undulate-crisped. Inflorescences cymose, 30–100(–150) × 10–80 cm; branches glabrous. Involucres (2–)3–5 per cluster, 3–4 mm, glabrous or sparsely pubescent. Flowers 2.5–3 mm; perianth white to pink, rarely yellowish, glabrous or sparsely pubescent. 2n = 80.


Phenology: Flowering May–Oct.
Habitat: Sandy to gravelly or clayey flats and slopes, mixed grassland and chaparral communities, oak and conifer woodlands
Elevation: 0-1200 m

Discussion

Variety auriculatum is a highly variable taxon that occurs along the coast and in the adjacent mountains (Alameda, Contra Costa, Humboldt, Lake, Marin, Monterey, Napa, San Benito, San Francisco, San Luis Obispo, San Mateo, Santa Clara, Santa Cruz, Solano, Sonoma, and western Stanislaus counties).

A related and as yet undescribed variety, known only from the Antioch sand dunes area of Contra Costa County, California, is the host for the federally endangered Lange’s metalmark butterfly (Apodemia mormo langei).

Selected References

None.

Lower Taxa

None.
James L. Reveal +
(Bentham) J. P. Tracy ex Jepson +
Eriogonum auriculatum +
Ear-shaped wild buckwheat +
0-1200 m +
Sandy to gravelly or clayey flats and slopes, mixed grassland and chaparral communities, oak and conifer woodlands +
Flowering May–Oct. +
Eriogonum latifolium var. alternans +  and Eriogonum latifolium subsp. auriculatum +
Eriogonum nudum var. auriculatum +
Eriogonum nudum +
variety +