Trifolium amoenum |
Trifolium lupinaster |
|
---|---|---|
showy Indian clover, two-fork clover |
lupine clover |
|
Habit | Herbs annual, 45–65 cm, canescent. | Herbs perennial, 15–50 cm, glabrous or curly-pilose. |
Stems | erect, branched from base and distally, or unbranched. |
erect, unbranched or branched distally. |
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 adnate entire length of petiole, sheathing, lanceolate-oblong, 0.8–1.3 cm, margins sharply and finely serrate, pilose, apex acute; petiole 0.5–0.7 cm; petiolules 0.5 mm; leaflets (3–)5(–9), blades elliptic to linear-elliptic, 1–4 × 0.3–1.4 cm, base cuneate, veins prominent, cartilagenous, ending in sharp, curved teeth, margins setaceous, apex acute to obtuse, surfaces glabrous except midrib abaxially. |
Inflorescences | terminal or axillary, 30–50-flowered, bluntly conic, ellipsoid, globose, or subglobose, 1.5–3 × 1.5–2.5 cm; involucres absent. |
terminal or axillary, 10–30-flowered, hemispheric or globose, 1.7–2.3 × 2.7–3.3 cm; involucres oblique, to 0.5 mm, wavy to toothed. |
Peduncles | 5–15 cm. |
1–5 cm. |
Pedicels | absent; bracteoles cuplike, to 0.5 mm. |
erect or horizontal, 1–3 mm; bracteoles broadly shell-shaped, sometimes connate into lobed ridge, to 0.5 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. |
11–17 mm; calyx campanulate, oblique, 6–9 mm, glabrous or sparsely hairy distally and along veins, veins 10, tube 3 mm, lobes subequal, pilose, abaxial slightly longer, subulate, orifice open; corolla white to rose-purple, 10–15 mm, banner rolled into open tube, arched upwards distally, 10–15 × 4–5 mm, apex broadly rounded or acute, apiculate. |
Legumes | obovoid, 4 mm. |
oblong, 6–8 mm. |
Seeds | 1, dark brown, ellipsoid, 2–3 mm, smooth. |
3–6, dark brown or gray-brown, globose-reniform, 1.5–2 mm, slightly roughened, dull. |
2n | = 16, 32, 40, 48. |
|
Trifolium amoenum |
Trifolium lupinaster |
|
Phenology | Flowering Apr–May. | Flowering Jun. |
Habitat | Grassy slopes, swales, clay soils. | Forest glades, meadows. |
Elevation | 0–100 m. (0–300 ft.) | 0–400 m. (0–1300 ft.) |
Distribution |
CA
|
AK; Asia (n China, Russia) [Introduced in North America] |
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.) |
Populations of Trifolium lupinaster in Alaska appear to have been introduced as a potential forage crop and spread from cultivation (D. F. Murray and H. F. Drury 1974). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 11. | FNA vol. 11. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | Lupinaster pentaphyllus, Pentaphyllon lupinaster | |
Name authority | Greene: Fl. Francisc., 27. (1891) | Linnaeus: Sp. Pl. 2: 766. (1753) |
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