Snow Mountain Buckwheat

Eriogonum nervulosum is found infrequently in small, widely scattered populations in the southern half of the North Coast Ranges. There are six known locations, and no doubt more remain to be found. Except for a Sonoma County site, the plants are found on ridges that separate Colusa and Lake counties, from Snow Mountain in the north to southwest of Clear Lake in the south. The species is found also in the Confusion Canyon area south and west of the lake. It is an ideal rock-garden introduction, although it grows only on grayish or reddish-brown serpentine soils in the wild.

Herbs, spreading, matted, synoecious, 0.2-1 × 1-3(-5) dm, tomentose. Stems: caudex spreading; aerial flowering stems erect or nearly so, slender, solid, not fistulose, arising at nodes of caudex branches and at distal nodes of short, nonflowering aerial branches, 0.2-0.6(-1) dm, tomentose. Leaves in compact basal rosettes; petiole 0.5-1 cm; blade broadly ovate, 0.4-0.8(-1) × 0.5-1 cm, densely white- to brownish-tomentose abaxially, thinly floccose or glabrous and green adaxially, margins plane to slightly revolute. Inflorescences subcapitate, 0.5-1.5 × 1-2 cm; branches tomentose; bracts 3-6, leaflike, lanceolate, 0.3-0.6 × 0.1-0.3 mm. Involucres 1 per node, turbinate, 3-4 × 2-3 mm, villous; teeth 6-8, erect, 0.4-0.8 mm. Flowers 3.5-5.5 mm, including 0.5-0.8 mm stipelike base; perianth white to ochroleucous, becoming pinkish rose or deep red, glabrous; tepals monomorphic, obovate; stamens exserted, 4-5 mm; filaments pilose proximally. Achenes light brown, 4.5-5 mm, glabrous.

Calif.

Flowering May-Oct.

Serpentine slopes and outcrops, mixed grassland communities, oak and conifer woodlands; of conservation concern; 300-2100m.

Eriogonum ursinum S. Watson var. nervulosum S. Stokes, Eriogonum, 114. 1936

Eriogonum nervulosum is a species of wild buckwheat known by the common name Snow Mountain buckwheat. This uncommon plant is endemic to the inland North Coast Ranges of California, where it is known from only a handful of occurrences, most of which are in Lake County. It is named for Snow Mountain, a local peak.

In the wild the plant grows in serpentine soils in its native mountains.