Trifolium bifidum |
Trifolium buckwestiorum |
|
---|---|---|
notch-leaf clover, Pinole clover, piñole clover |
Santa Cruz clover |
|
Habit | Herbs annual, 5–55 cm, sparsely pubescent or glabrous. | Herbs annual, 5–40 cm, glabrous. |
Stems | erect, branched. |
decumbent to ascending or erect, slightly branched. |
Leaves | palmate; stipules ovate to lanceolate, 0.8–1.5 cm, margins entire or slightly serrate, apex acicular; petiole 1–7 cm; petiolules to 0.5 mm; leaflets 3, blades narrowly obcordate, obovate, oblanceolate, or linear, 1–2.5 × 0.3–0.7 cm, base cuneate, veins moderately thickened, margins serrate distally or entire, apex rounded, truncate, shallowly to deeply retuse, or deeply 2-fid, surfaces glabrous or hairy abaxially along midvein. |
palmate; stipules whitish with prominent green veins, ovate, 0.3–0.5 cm, margins lacerate, apex acute to acuminate; petiole 1–2.4 cm; petiolules to 0.5 mm; leaflets 3, blades obovate to elliptic, 0.6–1.5 × 0.3–0.8 cm, base cuneate, veins ± thickened distally, margins denticulate, sometimes entire proximally, apex rounded, acute, or retuse, surfaces glabrous. |
Inflorescences | axillary or terminal, 5–30-flowered, globose to subglobose, 0.8–1.5 × 0.8–1.5 cm, rachis prolonged beyond flowers; involucres a very narrow rim, to 0.5 mm. |
terminal or axillary, 15–20-flowered (early inflorescences hidden in stipules, subsessile, 2–5-flowered, flowers cleistogamous), subglobose, 0.5–0.8 × 0.6–0.8 cm; involucres flattened or shallowly bowl-shaped, 6–8 mm, when folded, nearly hiding calyces, glabrous or sparsely hairy, lobes 4 or 5, ± parallel-sided, 3 or 4-toothed. |
Peduncles | 3–8 cm. |
1–3.5 cm. |
Pedicels | reflexed in fruit, 1–3 mm; bracteoles broadly triangular, membranous, to 0.5 mm. |
straight, to 0.5 mm; bracteoles absent. |
Flowers | 6–8 mm; calyx campanulate, 3–3.6 mm, slightly hairy or glabrous, veins 10, tube 1–1.5 mm, lobes unequal, subulate, margins green or purple, orifice open; corolla pink or purple, 5–7 mm, banner elliptic to oblong, 5–7 × 3–4 mm, apex rounded, apiculate. |
7–8 mm; calyx tubular, 4–5 mm, glabrous, veins 10, tube 2–2.5 mm, lobes subequal, triangular, margins conspicuously 2 or 3-toothed, apex aristate, orifice open; corolla pale pink or white, 6–7 mm, banner oblong, 5–7 × 1 mm, apex emarginate or erose. |
Legumes | stipitate, obovoid, 3–4 mm. |
ovoid, 2.5 mm. |
Seeds | 1 or 2, brown, mottled, oblong, 2–3 mm, smooth. |
1, dark brown, slightly mottled, ovoid, 2 mm, smooth. |
2n | = 16. |
|
Trifolium bifidum |
Trifolium buckwestiorum |
|
Phenology | Flowering Apr–Jun. | Flowering May–Jun. |
Habitat | Open woodlands, fields, roadsides, slopes, stream margins, meadows. | Meadows, roadsides, grassy hillsides. |
Elevation | 0–1200 m. (0–3900 ft.) | 0–300 m. (0–1000 ft.) |
Distribution |
CA; OR; WA; BC; Mexico (Baja California)
|
CA |
Discussion | Trifolium bifidum ranges from Baja California, Mexico, northward through California to scattered sites in Oregon, Washington, and British Columbia. Recent re-evaluation of Trifolium bifidum and related species showed complete overlap in characters for the two varieties that have been recognized previously, with no clear distinctions between them (L. Rogers, pers. comm.). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Trifolium buckwestiorum, which ranges from Mendocino to Monterey counties, is unique among clovers in North America because of its aboveground cleistogamous, axillary flowers. The only other clover in North America that produces cleistogamous flowers is T. amphianthum, which produces its cleistogamous flowers at ground level and then pushes them into the substrate. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 11. | FNA vol. 11. |
Parent taxa | Fabaceae > subfam. Faboideae > Trifolium | Fabaceae > subfam. Faboideae > Trifolium |
Sibling taxa | ||
Synonyms | T. bifidum var. decipiens, T. greenei, T. hallii | |
Name authority | A. Gray: Proc. Calif. Acad. Sci. 3: 102. (1864) | Isely: Madroño 39: 90, fig. 2. (1992) |
Web links |
|