Kern Plateau horkeliella or false horkelia

Horkelia purpurascens S. Watson, Proc. Amer. Acad. Arts 11: 148. 1876; Ivesia purpurascens (S. Watson) D. D. Keck; Potentilla purpurascens (S. Watson) Greene

Plants green or grayish green to gray, non-glandular hairs sparse to dense, often obscuring stipitate-glandular ones. Basal leaves (5–)7–17(–20) cm; petiole 1–5 cm; leaflets 15–30(–35) per side, (2–)3–10(–20) mm, divided into 3–6 ultimate segments, hirsute (sometimes densely so) and villous (especially marginally), infrequently viscid-stipitate-glandular, or nearly glabrous except for villous tuft at apex. Cauline leaves 2–4, 2–10 cm. Inflorescences ± open. Pedicels (1–)2–10(–15) mm. Flowers 10–15 mm diam., epicalyx bractlets linear to narrowly ovate, 1.5–3 mm; sepals 3–6 mm, hirsute, sparsely villous, sometimes minutely glandular or stipitate-glandular; petals oblanceolate to narrowly spatulate or oblong, 3–7 mm; filaments 1–2.5 mm, filament opposite center of sepal shorter than those on either side, anthers 0.5–0.8(–1) mm; styles 2.5–4 mm.

Flowering summer. Dry granitic meadows at edges of conifer woodlands; 1400–2900 m; Calif.

Typical Horkeliella purpurascens occurs on the Kern Plateau on the western slope of the southern Sierra Nevada in Kern and Tulare counties. More densely hairy populations farther south in the Piute, Scodie, and Tehachapi mountains of Kern County tend to have more congested inflorescences, shorter leaves, and fewer carpels; they may merit taxonomic recognition.