Lathyrus palustris

Lathyrus palustris L.

Lathyrus myrtifolius Muhl. ex Willd.

Lathyrus palustris L. ssp. pilosus (Cham.) Hultén

Lathyrus palustris L. var. linearifolius Ser.

Lathyrus palustris L. var. macranthus (T.G. White) Fernald

Lathyrus palustris L. var. meridionalis Butters & H. St. John

Lathyrus palustris L. var. myrtifolius (Muhl. ex Willd.) A. Gray

Lathyrus palustris L. var. pilosus (Cham.) Ledeb.

Lathyrus palustris L. var. retusus Fernald & H. St. John

Orobus myrtifolius Alef.

Marsh Vetchling, Marsh Pea

About plant names...

Marsh pea is native to Europe, Asia, and North America. It has an affinity for wet freshwater areas.

Identification: A vinelike plant 12-48" (30-121 cm) long, with stems that are often “winged.” That is, viewed in cross-section, the central circle of the stem has two flat projections emerging from opposite sides. Each projection is ¹/₁₆-⅛" (2-5 mm) wide. Some stems and even some entire plants lack these wings. Stems may also be angular or grooved. (Confused yet?) Branch tips have tendrils that latch onto other plants. Leaves are pinnate—composed of opposing pairs of leaflets. Leaflets often form the shape of a V, and may be asymmetrical. They are lance-shaped, about 1-2½" (2.5-6.3 cm) long and up to ½" (1.3 cm) wide, green on top, pale green below. Flowers are purple and white, about ¾" (1.9 cm) in size. They appear in clusters of 2-8, from June to August. Seedpods are 1-2½" (2.5-6.3 cm) long × ¼" (6.3 mm) around, similar to those of related garden peas, but smaller.

Online References:

Lathyrus palustris at Illinois Wildflowers

Lathyrus palustris at Minnesota Wildflowers

Lathyrus palustris at the University of Wisconsin's Robert W. Freckmann Herbarium

Lathyrus palustris on Ontario Wildflowers

Lathyrus palustris on eFloras

Lathyrus palustris from the Jepson Manual

References:

Newcomb, Lawrence, Morrison, Gordon (Illus.), Newcomb’s Wildflower Guide, Little, Brown and Company, 1977, p. 114

8/8/2010 · Beaver Brook Association Conservation Lands, Hollis, NH
≈ 7 × 10" (16 × 25 cm)

8/8/2010 · Beaver Brook Association Conservation Lands, Hollis, NH
≈ 7 × 10" (16 × 25 cm)

7/5/2015 · Jeff Smith Trail, Hollis, NH
≈ 8 × 5" (19 × 13 cm)

7/5/2015 · Jeff Smith Trail, Hollis, NH
≈ 5 × 8" (13 × 19 cm)

6/20/2016 · Wildlife Pond Trail, Beaver Brook Conservation Area, Hollis, NH

8/8/2010 · Beaver Brook Association Conservation Lands, Hollis, NH
≈ 3 × 2½" (7.8 × 6.7 cm)

6/20/2016 · Wildlife Pond Trail, Beaver Brook Conservation Area, Hollis, NH

8/2/2010 · Beaver Brook Association Conservation Lands, Hollis, NH
≈ 4½ × 3" (11 × 7.9 cm)

7/2/2017 · Wildlife Pond, Beaver Brook Conservation Area, Hollis, NH
≈ 2 × 2½" (5.8 × 6.1 cm)

Lathyrus palustris description by Thomas H. Kent, last updated 12 Oct 2018.

© FloraFinder.org. All rights reserved.

8/8/2010 · Beaver Brook Association Conservation Lands, Hollis, NH
≈ 3 × 5" (8.4 × 12 cm)

7/5/2015 · Jeff Smith Trail, Hollis, NH
≈ 5 × 6" (12 × 14 cm)

7/5/2015 · Jeff Smith Trail, Hollis, NH
≈ 3 × 3" (8 × 7.6 cm)

6/20/2016 · Wildlife Pond Trail, Beaver Brook Conservation Area, Hollis, NH

8/8/2010 · Beaver Brook Association Conservation Lands, Hollis, NH
≈ 4½ × 3" (11 × 7.5 cm)

6/20/2016 · Wildlife Pond Trail, Beaver Brook Conservation Area, Hollis, NH

7/17/2012 · Beaver Brook Association Conservation Lands, Hollis, NH
≈ 3½ × 2½" (9.8 × 6.6 cm)

7/5/2015 · Jeff Smith Trail, Hollis, NH
≈ 6 × 4" (14 × 10 cm)

7/5/2015 · Jeff Smith Trail, Hollis, NH
≈ 5 × 4½" (13 × 11 cm)

Winged stem. (Flowers in this image are not marsh vetchling.) · 7/17/2012 · Beaver Brook Association Conservation Lands, Hollis, NH
≈ 7 × 4½" (17 × 11 cm)

7/17/2012 · Beaver Brook Association Conservation Lands, Hollis, NH
≈ 6 × 4" (15 × 10 cm)

7/5/2015 · Jeff Smith Trail, Hollis, NH
≈ 5 × 7" (13 × 16 cm)

8/2/2010 · Beaver Brook Association Conservation Lands, Hollis, NH
≈ 8 × 5" (19 × 13 cm)

7/2/2017 · Wildlife Pond, Beaver Brook Conservation Area, Hollis, NH
≈ 2 × 2½" (5.9 × 6.2 cm)

Range:

About this map...