Trifolium macrocephalum |
Trifolium echinatum |
|
---|---|---|
big-head clover, large-head clover |
prickly clover |
|
Habit | Herbs perennial, 5–25 cm, villous. | Herbs annual, 10–50 cm, appressed-hairy. |
Stems | erect or ascending, branched. |
erect or ascending, branched from base. |
Leaves | palmate; stipules ovate, obovate, or oblong, 1–3 cm, margins entire, irregularly lobed, or serrate, apex acute or acuminate; petiole 1–14 cm; petiolules 0.9–1.2 mm; leaflets (5–)7–9, blades broadly to narrowly obovate, often folded, 1–2.7 × 0.4–1.1 cm, base cuneate, veins thickened, especially distally, margins serrulate, apex rounded or truncate, apiculate, surfaces villous abaxially, sparsely villous to glabrate adaxially. |
palmate; stipules ovate-lanceolate, 0.4–0.8 cm, margins entire, apex acuminate, flared outward; petiole 0.5–6 cm; petiolules 1+ mm; leaflets 3, blades obovate, elliptic, or narrowly elliptic, 0.8–2.5 × 0.4–1.6 cm, base cuneate, veins prominent, thickened abaxially, margins denticulate or serrate, apex rounded, acute, or apiculate, surfaces sparsely hairy. |
Inflorescences | terminal, 20–32-flowered, globose or ovoid-ellipsoid, 2.5–8 × 3–7 cm; involucres absent. |
terminal and axillary, 15–50-flowered, obconic or obovoid, 1–2 × 1–1.6 cm; involucres absent. |
Peduncles | 2–8 cm. |
0.8–2 cm. |
Pedicels | erect, 1–1.5 mm; bracteoles broadly ovate, membranous, to 0.5 mm, truncate. |
absent; bracteoles absent. |
Flowers | 20–30 mm; calyx campanulate, 10–22 mm, villous, veins 10–15, tube 2.5–4 mm, lobes subequal, subulate, plumose, orifice open; corolla white, creamy white, or pinkish, keel petals deep pink, 20–28 mm, banner ovate or oblong, 20–28 × 10–13 mm, apex rounded or slightly emarginate. |
9–11 mm; calyx campanulate, 5–8 mm, glabrescent, veins 10, tube 2–3 mm, lobes unequal, triangular-elliptic, stellate-spreading, orifice closed by bilabiate callosities; corolla creamy white, 8–10 mm, banner oblong-spatulate, 8–10 × 2–3 mm, apex acute. |
Legumes | ovoid, 4–5 mm. |
obovoid, leathery distally, transversely dehiscent, 1.6–2 mm. |
Seeds | 1 or 2, yellow or reddish, mitten-shaped to ellipsoid, 2.5–3 mm, smooth. |
1, tan or brown, ovoid, 1.2–1.4 mm, smooth, glossy. |
2n | = 32, 48. |
= 16. |
Trifolium macrocephalum |
Trifolium echinatum |
|
Phenology | Flowering Apr–Jun. | Flowering Mar–Jun. |
Habitat | Rocky places, hard, compacted clay-gumbo, lava beds, sage-covered slopes, full sun. | Disturbed roadsides, fields. |
Elevation | 80–2500 m. [260–8200 ft.] | 100–300 m. [300–1000 ft.] |
Distribution |
CA; ID; NV; OR; WA
|
AL; LA; c Europe; s Europe; w Asia; n Africa [Introduced in North America] |
Discussion | Trifolium macrocephalum has the largest inflorescences of any clover. Trifolium megacephalum Nuttall (1818) is an illegitimate replacement name for Lupinaster macrocephalum Pursh. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Trifolium echinatum was recently discovered in Ouachita Parish in a disturbed construction area; an older record (1902) from ballast in Portland, Oregon, appears to have been a waif. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 11. | FNA vol. 11. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | Lupinaster macrocephalum | |
Name authority | (Pursh) Poiret in J. Lamarck et al.: Encycl., suppl. 5: 336. (1817) | M. Bieberstein: Fl. Taur.-Caucas. 2: 216. (1808) |
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