Trifolium macrocephalum |
Trifolium piorkowskii |
|
---|---|---|
big-head clover, large-head clover |
marshmallow clover, Piorkowski's clover |
|
Habit | Herbs perennial, 5–25 cm, villous. | Herbs annual, 7–30 cm, glabrous. |
Stems | erect or ascending, branched. |
erect or ascending, sparsely to much branched. |
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, 1–1.5 cm, margins entire, apex acute-acuminate; petiole 8–12 cm; petiolules 1 mm; leaflets 3, blades oblanceolate or obovate, 2.8 × 1.9 cm, base cuneate, veins delicate, margins entire or shallowly dentate distally, lateral veins sometimes ending in a bristle, apex rounded to acute, surfaces glabrous. |
Inflorescences | terminal, 20–32-flowered, globose or ovoid-ellipsoid, 2.5–8 × 3–7 cm; involucres absent. |
axillary or terminal, 3–16-flowered, in 1–3 whorls, subglobose, 2–2.8 × 1.8–2.6 cm; involucres bowl-shaped, 6–15 mm, lobes 6–8, broadly lanceolate, margins entire, acuminate, apex 3–5-fid. |
Peduncles | 2–8 cm. |
5–15 cm. |
Pedicels | erect, 1–1.5 mm; bracteoles broadly ovate, membranous, to 0.5 mm, truncate. |
straight, 0.5–1 mm; 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. |
12–14 mm; calyx campanulate, 5–8 mm, glabrous, veins 10, tube 2.5–4 mm, lobes 11–15, unequal, abaxial 3–5 forked, adaxial unbranched, orifice open; corolla creamy white to pinkish, 11–13 mm, banner ovate, inflated entire length in fruit, not distally twisted, 11–13 × 5–7 mm, apex rounded. |
Legumes | ovoid, 4–5 mm. |
ellipsoid, 5–6 mm. |
Seeds | 1 or 2, yellow or reddish, mitten-shaped to ellipsoid, 2.5–3 mm, smooth. |
1 or 2, gray-brown, black-mottled, subglobose, 2.5 mm, smooth. |
2n | = 32, 48. |
|
Trifolium macrocephalum |
Trifolium piorkowskii |
|
Phenology | Flowering Apr–Jun. | Flowering Apr–May. |
Habitat | Rocky places, hard, compacted clay-gumbo, lava beds, sage-covered slopes, full sun. | Shallow, vernally wet depressions on volcanic flats, banks of watercourses flowing through open rocky grassland, transitional habitats with scattered chaparral and conifers. |
Elevation | 80–2500 m. [260–8200 ft.] | 300–800 m. [1000–2600 ft.] |
Distribution |
CA; ID; NV; OR; WA
|
CA |
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 piorkowskii is known only from Shasta County. (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) | Rand. Morgan & A. L. Barber: Novon, 23: 65, plate 1. (2014) |
Web links |