The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

aspen pea, aspen peavine, aspen vetchling, plateau peavine, plateau vetchling

aspen peavine, lanszwert's pea, lanszwert's vetchling, Nevada pea, Nevada peavine, Nevada sweet pea, pinewood peavine, Rocky Mountain sweetpea, thick-leaf pea, thick-leaf peavine

Habit Herbs perennial, from rhizome, glabrous. Herbs perennial, from rhizome, glabrous or sparsely pubescent.
Stems

angled, sprawling to erect, basally branched 0–3 times, 2–8 dm.

angled, erect, sprawling, or climbing, basally branched 0–4 times, 1–8 dm.

Leaves

3–8 cm;

tendrils well developed, often branched;

stipules lanceolate, 8–12 × 2–5 mm, much smaller than leaflets;

leaflets 6–10, usually paired, blades ovate, 20–40 × 10–20 mm, surfaces glabrous.

(0.5–)1–8 cm;

tendrils mucronate to well developed;

stipules linear to lanceolate, 5–25 × 1–6 mm, much smaller than leaflets;

leaflets 2–10, scattered, blades lanceolate or linear, 20–70 × 2–20 mm, surfaces glabrous or sparsely pubescent.

Inflorescences

2–5-flowered, 4–7 cm.

2–6-flowered, 2–10 cm.

Flowers

15–20 mm;

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

corolla white to slightly pink or lavender, banner erect, blade longer than claw, wings equal to keel;

ovary glabrous.

7–15 mm;

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

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

ovary glabrous.

Legumes

30–50 × 5–15 mm.

25–45 × 6–10 mm.

Lathyrus laetivirens

Lathyrus lanszwertii

Phenology Flowering Apr–Jul.
Habitat Flats, hillsides, sagebrush com­munities, pinyon-juniper, oak, pine, aspen and Douglas-fir forests.
Elevation 1200–3200 m. (3900–10500 ft.)
Distribution
from FNA
AZ; CO; NM; NV; UT
[WildflowerSearch map]
[BONAP county map]
from USDA
w North America
[WildflowerSearch map]
[BONAP county map]
Discussion

C. L. Hitchcock (1952), S. L. Welsh et al. (1987), and D. Isely (1998) placed Lathyrus laetivirens within the L. lanszwertii complex, whereas R. C. Barneby (1989) treated it as a separate species.

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

Varieties 5 (5 in the flora).

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

Key
1. Stems (2–)3–8 dm, usually climbing, sometimes sprawling or erect; tendrils well developed, usually branched.
→ 2
2. Leaflets 8–10; corollas blue-purple; California northward to Washington, eastward to Colorado and Wyoming.
var. lanszwertii
2. Leaflets 6–8; corollas white; w Colorado, c Utah, Wyoming.
var. pallescens
1. Stems 1–3(–4) dm, usually erect (sometimes var. bijugatus sprawling or climbing); tendrils reduced to simple bristles less than 1 cm.
→ 3
3. Leaflets 2–4; e Washington, adjacent Idaho, Montana, British Columbia.
var. bijugatus
3. Leaflets 4–8; California northward to sc Washington and eastward to New Mexico, Colorado, and Wyoming.
→ 4
4. Flowers 7–10 mm; California, Nevada, Oregon, Washington.
var. aridus
4. Flowers 10–15 mm; Arizona, Colorado, New Mexico, Utah, Wyoming.
var. leucanthus
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. lanszwertii, L. latifolius, L. littoralis, L. nevadensis, 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
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. latifolius, L. littoralis, L. nevadensis, 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. lanszwertii var. aridus, L. lanszwertii var. bijugatus, L. lanszwertii var. lanszwertii, L. lanszwertii var. leucanthus, L. lanszwertii var. pallescens
Synonyms L. lanszwertii var. laetivirens, L. leucanthus var. laetivirens
Name authority Greene ex Rydberg: Fl. Colorado, 217. (1906) Kellogg: Proc. Calif. Acad. Sci. 2: 150, fig. 44. (1863)
Web links