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gesse des marais, marsh pea, marsh peavine, marsh vetchling

purple peavine, Sierra Nevada pea, Sierra Nevada sweet pea, Sierra pea, Sierra peavine

Habit Herbs perennial, from rhizome, glabrous or pubescent. Herbs perennial, from rhizome, pubescent except glabrous on legumes and leaflets adaxially.
Stems

narrowly to broadly winged, sprawling or climbing, basally branched 0–4 times, 2–10 dm.

angled, erect, sprawling, or climbing, basally branched 0–several times, 1–6 dm.

Leaves

1–6 cm;

tendrils well developed;

stipules ovate-lanceolate to linear, 5–25 × 1–10 mm, much smaller than leaflets;

leaflets 4–8, paired, blades lanceolate to linear, 15–75 × 2–20 mm, surfaces glabrous, glabrate, or pubescent.

2–10 cm;

tendrils mucronate (less than 1 cm) to well developed;

stipules linear, 5–25 × 1–8 mm, much smaller than leaflets;

leaflets 4–12, usually scattered, blades broadly ovate to lanceolate or linear, (17–)20–110 × 2–30(–37) mm, surfaces usually glabrous, rarely finely pubescent.

Inflorescences

2–7-flowered, 3–15 cm.

2–10-flowered, 3–15 cm.

Flowers

10–15 mm;

calyx lobes unequal, lateral lobes deltate, shorter than tube;

corolla blue-purple, banner erect, blade equal to claw, wings equal to keel;

ovary glandular-pubescent.

12–22 mm;

calyx lobes unequal, lateral lobes deltate, usually shorter than tube;

corolla blue-purple to pink-purple or white, banner erect, blade longer than claw, wings equal to keel;

ovary glabrous.

Legumes

25–60 × 4–8 mm.

20–30(–45) × 5–10 mm.

2n

= 14.

Lathyrus palustris

Lathyrus nevadensis

Phenology Flowering Apr–Aug.
Habitat Coastal and inland wetlands.
Elevation 0–1800 m. (0–5900 ft.)
Distribution
from FNA
AK; AL; AR; CA; CO; CT; DC; DE; IA; IL; IN; KY; MA; MD; ME; MI; MN; MO; NC; ND; NE; NH; NJ; NY; OH; OR; PA; RI; SD; TN; VA; VT; WA; WI; WV; BC; MB; NB; NL; NS; NU; ON; PE; QC; SK; SPM
[WildflowerSearch map]
[BONAP county map]
from USDA
w North America
[WildflowerSearch map]
[BONAP county map]
Discussion

Morphological variation within Lathyrus palustris is extensive. Although the most distinctive forms (see synonyms) have been accorded formal nomenclatural recognition (M. L. Fernald 1911; C. L. Hitchcock 1952), intergradation among these mostly sympatric ecotypes is widespread (D. Isely 1998). In Nunavut, it is known only from Akimiski Island in James Bay.

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

Varieties 3 (3 in the flora).

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

Key
1. Corollas blue-purple to pink-purple; British Columbia, California, w Oregon, w, c Washington.
var. nevadensis
1. Corollas white; ne Oregon, e Washington, adja­cent Idaho.
→ 2
2. Leaves 4–10 cm; leaflets 6–10; tendrils well developed; flowers 5–10, 12–18 mm.
var. parkeri
2. Leaves 2–5 cm; leaflets 4 or 6; tendrils reduced to bristles, (usually less than 1 cm); flowers 2–4, 18–22 mm.
var. cusickii
Source FNA vol. 11. FNA vol. 11.
Parent taxa Fabaceae > subfam. Faboideae > Lathyrus Fabaceae > subfam. Faboideae > Lathyrus
Sibling taxa
L. angulatus, L. aphaca, L. biflorus, L. brachycalyx, L. brownii, L. cicera, L. decaphyllus, L. delnorticus, L. eucosmus, L. glandulosus, L. graminifolius, L. grimesii, L. hirsutus, L. hitchcockianus, L. holochlorus, L. japonicus, L. jepsonii, L. laetivirens, L. lanszwertii, L. latifolius, L. littoralis, L. nevadensis, L. nissolia, L. ochroleucus, L. odoratus, L. pauciflorus, L. polyphyllus, L. pratensis, L. pusillus, L. rigidus, L. sphaericus, L. splendens, L. sulphureus, L. sylvestris, L. tingitanus, L. torreyi, L. tracyi, L. tuberosus, L. venosus, L. vestitus
L. angulatus, L. aphaca, L. biflorus, L. brachycalyx, L. brownii, L. cicera, L. decaphyllus, L. delnorticus, L. eucosmus, L. glandulosus, L. graminifolius, L. grimesii, L. hirsutus, L. hitchcockianus, L. holochlorus, L. japonicus, L. jepsonii, L. laetivirens, L. lanszwertii, L. latifolius, L. littoralis, L. nissolia, L. ochroleucus, L. odoratus, L. palustris, L. pauciflorus, L. polyphyllus, L. pratensis, L. pusillus, L. rigidus, L. sphaericus, L. splendens, L. sulphureus, L. sylvestris, L. tingitanus, L. torreyi, L. tracyi, L. tuberosus, L. venosus, L. vestitus
Subordinate taxa
L. nevadensis var. cusickii, L. nevadensis var. nevadensis, L. nevadensis var. parkeri
Synonyms L. myrtifolius, L. palustris var. linearifolius, L. palustris var. macranthus, L. palustris var. myrtifolius, L. palustris subsp. pilosus, L. palustris var. pilosus, L. palustris var. retusus
Name authority Linnaeus: Sp. Pl. 2: 733. (1753) S. Watson: Proc. Amer. Acad. Arts 11: 133. (1876)
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