Trifolium amoenum |
Trifolium leibergii |
|
---|---|---|
showy Indian clover, two-fork clover |
Leiberg's clover |
|
Habit | Herbs annual, 45–65 cm, canescent. | Herbs perennial, 10–15 cm, canescent. |
Stems | erect, branched from base and distally, or unbranched. |
erect, aerial stems sparsely branched. |
Leaves | palmate; stipules ovate-oblong, 0.5–1.8 cm, margins entire, toothed, or irregularly lobed, apex acuminate; petiole 0.5–10 cm; petiolules to 1 mm; leaflets 3, blades broadly obovate or elliptic, 1.7–3.3 × 1.1–2 cm, base cuneate, veins fine, margins entire or denticulate, apex rounded, obtuse, or retuse, surfaces pilose, abaxial less so. |
palmate; stipules lanceolate, 0.7–1.5 cm, margins coarsely spinulose-dentate, apex acuminate; petiole 1–3 cm; petiolules to 0.5 mm; leaflets 3, blades obovate, rhombic, or elliptic, sometimes folded, 0.9–1.5 × 0.5–1.3 cm, base cuneate, veins very thick, margins coarsely spinulose-dentate, apex rounded, long-apiculate, surfaces canescent. |
Inflorescences | terminal or axillary, 30–50-flowered, bluntly conic, ellipsoid, globose, or subglobose, 1.5–3 × 1.5–2.5 cm; involucres absent. |
axillary, 5–25-flowered, globose, 2.2–2.5 × 2.3–2.7 cm; involucres a narrow, papery, irregular rim, to 0.5 mm. |
Peduncles | 5–15 cm. |
2–4.5 cm. |
Pedicels | absent; bracteoles cuplike, to 0.5 mm. |
reflexed in fruit, 1.5–4 mm; bracteoles triangular, to 0.2 mm. |
Flowers | 13–16 mm; calyx tubular, 9–12 mm, pubescent, veins 20–30, tube 3 mm, lobes nearly equal, appearing rigidly erect, linear-setaceous, plumose, sinuses acute, orifice open; corolla white to pink with purple tips, 12–16 mm, banner ovate-oblong, 12–15 × 4 mm, apex broadly rounded, emarginate. |
11–15 mm; calyx campanulate, 5–11 mm, pilose, veins 10, tube 1.8–2.2 mm, lobes subequal, lanceolate-setiform, orifice open; corolla creamy white with purplish veins, becoming pinkish purple-tinged, 10.5–13 mm, banner broadly rhombic-ovate or obovate, 10.5–13 × 5–7 mm, apex rounded, slightly emarginate. |
Legumes | obovoid, 4 mm. |
ovoid, 3–4 mm. |
Seeds | 1, dark brown, ellipsoid, 2–3 mm, smooth. |
1 or 2, brown, mitten-shaped, 1.5–2 mm, smooth. |
Trifolium amoenum |
Trifolium leibergii |
|
Phenology | Flowering Apr–May. | Flowering Jun–Jul. |
Habitat | Grassy slopes, swales, clay soils. | Open, rocky slopes and crests, ash-flows. |
Elevation | 0–100 m. (0–300 ft.) | 1900–2400 m. (6200–7900 ft.) |
Distribution |
CA
|
NV; OR |
Discussion | Trifolium amoenum was considered extinct (J. P. Smith Jr. 1984) but was rediscovered in 1993 (P. G. Connors 1994). Specimens of T. amoenum are known from Marin, Napa, San Mateo, Solano, and Sonoma counties; it appears to be extant in only single populations in each of Marin and Solano counties. Allozyme studies of the two known populations revealed fixed genetic differences between them (E. E. Knapp and Connors 1999). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Trifolium leibergii is known from only a few populations from Harney County, Oregon, and Elko County, Nevada. It is in the Center for Plant Conservation’s National Collection of Endangered Plants. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 11. | FNA vol. 11. |
Parent taxa | ||
Sibling taxa | ||
Name authority | Greene: Fl. Francisc., 27. (1891) | A. Nelson & J. F. Macbride: Bot. Gaz. 65: 58. (1918) |
Web links |