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canyon clover, Howell's clover

saline clover, water sack clover

Habit Herbs perennial, 30–100 cm, glabrous. Herbs annual, 15–55 cm, glabrous.
Stems

erect, fistulose, unbranched or branched distally.

erect, branched.

Leaves

palmate;

stipules ovate, 1.5–4.5 cm, margins usually entire, sometimes lobed, apex acuminate;

petiole 0.5–20 cm;

petiolules 1–1.5 mm;

leaflets 3, blades ovate, elliptic, or rhombic, 3.5–9.5 × 2.3–5 cm, base cuneate, veins obscure, margins ± serrate, apex acute, rounded, or obtuse, surfaces glabrous.

palmate;

stipules ovate-oblong to lanceolate, 0.4–1.3 cm, sheathing proximally, margins entire or serrate, apex acuminate;

petiole 3–9 cm;

petiolules 0.5 mm;

leaflets 3, blades obovate to oblanceolate, 1.2–3 × 0.3–1.4 cm, base cuneate, veins fine, margins serrate, apex rounded or truncate, surfaces glabrous.

Inflorescences

terminal or axillary, 20–70-flowered, globose or ellipsoid, 2.5–4 × 2–2.5 cm, rachis prolonged beyond flowers, undivided or forked, often bearing sterile flower buds distally;

involucres absent.

axillary or terminal, 5–15-flowered, ellipsoid, 1–1.8 × 1.3–1.5 cm;

involucres flattened, 3–4 mm, shallowly incised, lobes 5–8, elliptic, apex rounded to truncate and irregularly erose, not split.

Peduncles

3–11 cm.

3.5–6 cm.

Pedicels

strongly reflexed in fruit, 1 mm;

bracteoles minute, blunt or acute, membranous.

erect, 1 mm;

bracteoles broadly ovate, to 0.5 mm.

Flowers

10–14 mm;

calyx campanulate, gibbous, 4–5.5 mm, glabrous, veins 10, tube 2–2.5 mm, lobes subequal, linear-lanceolate, orifice open;

corolla white, lemon yellow, or greenish yellow, 11–12 mm, banner elliptic-oblong, 11–12 × 4–5 mm, apex obtuse.

7–11 mm;

calyx campanulate-tubular, 2.5–5 mm, glabrous, veins 5, tube 1–2.5 mm, lobes unequal, lanceolate-subulate, orifice open;

corolla reddish purple, 7–9 mm, inflated in fruit, banner oblong, 7–9 × 3–4 mm, apex rounded, retuse.

Legumes

oblong or clavate, 4–5 mm.

stipitate, ovate-oblong, 4 mm.

Seeds

1–3, reddish black or brown, angular, mitten-shaped, 2.5 mm, smooth or slightly roughened, dull.

1 or 2, red-brown, ovoid-ellipsoid, 2 mm, smooth or papillate.

Trifolium howellii

Trifolium hydrophilum

Phenology Flowering Jun–Jul. Flowering Apr–May.
Habitat Wet stream banks, wet meadows, flood plains, shady woodlands, springs, thickets. Wet, alkaline soils, salt marshes.
Elevation 800–2000 m. (2600–6600 ft.) 0–300 m. (0–1000 ft.)
Distribution
from FNA
CA; OR
[WildflowerSearch map]
[BONAP county map]
from FNA
CA
[BONAP county map]
Discussion

Trifolium howellii is known from Del Norte, Humboldt, Siskiyou, and Trinity counties in California, and Clackamas, Douglas, Jackson, Josephine, Klamath, Lane, and Linn counties in Oregon (J. M. Gillett 1972). It has some of the largest leaves of any species of Trifolium in North America.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Trifolium hydrophilum is closely allied to T. depauperatum and is restricted to the Sacramento Valley, northwestern San Joaquin Valley, and central-western California; it grows in moist areas, sometimes in standing water (M. A. Vincent and D. Isely 2012).

(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
T. albopurpureum, T. alexandrinum, T. amoenum, T. amphianthum, T. andersonii, T. andinum, T. angustifolium, T. appendiculatum, T. arvense, T. attenuatum, T. aureum, T. barbigerum, T. barnebyi, T. beckwithii, T. bejariense, T. bifidum, T. bolanderi, T. brandegeei, T. breweri, T. buckwestiorum, T. calcaricum, T. campestre, T. carolinianum, T. cernuum, T. ciliolatum, T. columbinum, T. cyathiferum, T. dasyphyllum, T. dedeckerae, T. depauperatum, T. dichotomum, T. douglasii, T. dubium, T. echinatum, T. eriocephalum, T. fragiferum, T. friscanum, T. fucatum, T. glomeratum, T. gracilentum, T. grayi, T. gymnocarpon, T. haydenii, T. hirtum, T. hybridum, T. hydrophilum, T. incarnatum, T. jokerstii, T. kentuckiense, T. kingii, T. lappaceum, T. latifolium, T. leibergii, T. lemmonii, T. longipes, T. lupinaster, T. macilentum, T. macraei, T. macrocephalum, T. medium, T. microcephalum, T. microdon, T. monanthum, T. mucronatum, T. nanum, T. nigrescens, T. obtusiflorum, T. oliganthum, T. ornithopodioides, T. owyheense, T. palmeri, T. parryi, T. pinetorum, T. piorkowskii, T. plumosum, T. polyodon, T. pratense, T. productum, T. reflexum, T. repens, T. resupinatum, T. retusum, T. rollinsii, T. siskiyouense, T. sonorense, T. stoloniferum, T. striatum, T. subterraneum, T. suffocatum, T. thompsonii, T. tomentosum, T. trichocalyx, T. variegatum, T. vesiculosum, T. virginicum, T. willdenovii, T. wormskioldii
T. albopurpureum, T. alexandrinum, T. amoenum, T. amphianthum, T. andersonii, T. andinum, T. angustifolium, T. appendiculatum, T. arvense, T. attenuatum, T. aureum, T. barbigerum, T. barnebyi, T. beckwithii, T. bejariense, T. bifidum, T. bolanderi, T. brandegeei, T. breweri, T. buckwestiorum, T. calcaricum, T. campestre, T. carolinianum, T. cernuum, T. ciliolatum, T. columbinum, T. cyathiferum, T. dasyphyllum, T. dedeckerae, T. depauperatum, T. dichotomum, T. douglasii, T. dubium, T. echinatum, T. eriocephalum, T. fragiferum, T. friscanum, T. fucatum, T. glomeratum, T. gracilentum, T. grayi, T. gymnocarpon, T. haydenii, T. hirtum, T. howellii, T. hybridum, T. incarnatum, T. jokerstii, T. kentuckiense, T. kingii, T. lappaceum, T. latifolium, T. leibergii, T. lemmonii, T. longipes, T. lupinaster, T. macilentum, T. macraei, T. macrocephalum, T. medium, T. microcephalum, T. microdon, T. monanthum, T. mucronatum, T. nanum, T. nigrescens, T. obtusiflorum, T. oliganthum, T. ornithopodioides, T. owyheense, T. palmeri, T. parryi, T. pinetorum, T. piorkowskii, T. plumosum, T. polyodon, T. pratense, T. productum, T. reflexum, T. repens, T. resupinatum, T. retusum, T. rollinsii, T. siskiyouense, T. sonorense, T. stoloniferum, T. striatum, T. subterraneum, T. suffocatum, T. thompsonii, T. tomentosum, T. trichocalyx, T. variegatum, T. vesiculosum, T. virginicum, T. willdenovii, T. wormskioldii
Synonyms T. amplectens var. hydrophilum, T. depauperatum var. hydrophilum
Name authority S. Watson: Proc. Amer. Acad. Arts 23: 262. (1888) Greene: Man. Bot. San Francisco, 100. (1894)
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