Eriogonum twisselmannii

Herbs, matted, occasionally polygamodioecious, (0.2–)0.5–1.5 × 3–4 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–)0.5–1.2 dm, tomentose, with a whorl of 4–8 leaflike bracts ca. midlength, similar to leaf blades, 0.4–0.8 × 0.1–0.3 cm. Leaves in loose to congested basal rosettes; petiole 0.2–0.4 cm, thinly tomentose; blade oblanceolate to elliptic, 0.5–1 × (0.2–)0.4–0.6 cm, white- or grayish-tomentose abaxially, thinly tomentose to nearly glabrous and dull green adaxially. Inflorescences capitate, 0.7–1.5 cm wide; branches absent; bracts absent immediately below involucre. Involucres 1 per node, campanulate, (2.5–)4–5 × 4–6 mm; teeth 6–9, lobelike, strongly reflexed, (2–)3–5 mm. Flowers (4–)5–6 mm, including 1–1.3 mm stipelike base; perianth pale yellow, villous abaxially; tepals slightly dimorphic, those of outer whorl obtuse, 3–5 × 3–3.5 mm, those of inner whorl broadly oblanceolate, 5–6 × 2.5–3 mm; stamens exserted, 4–5 mm; filaments pilose proximally. Achenes light brown, 5–5.5 mm, glabrous except for sparsely pubescent beak.

Phenology: Flowering Jun–Sep.
Habitat: Rocky outcrops, montane conifer woodlands
Elevation: 2300-2600 m

Calif.

Discussion

Of conservation concern.

Eriogonum twisselmannii is a rare species of the southern Sierra Nevada and is known only from Slate Mountain and The Needles in Tulare County. It is worthy of being on a “watch” list of rare plants in California, but because of its remote location, it is not threatened.

Selected References

None.

Lower Taxa