[Peas, Peavines and Vetchlings: The Genus Lathyrus West of the Cascade Mountains of Oregon and Washington]

Yellow Pea, Yellow Vetchling

Lathyrus aphaca

Yellow Pea, Yellow Vetchling: Lathyrus aphaca

The photo above shows the upper stem of yellow vetchling as seen about 7 miles northeast of Roseburg, OR........late June 2005. Note the broad, arrowhead-shaped stipules and the simple, prehensile tendrils that arise from their axils.

Flower of Yellow Pea, Yellow Vetchling: Lathyrus aphacaThe photo at right shows a close-up of the calyx and corolla of yellow vetchling as seen about 7 miles northeast of Roseburg, OR................late June 2005. Note the glabrous calyx and the wide calyx teeth that are longer than the calyx tube.
Characteristics:

Yellow vetchling is a weedy annual with single to several slender and reclining to twining stems arising from 20-60 cm high. The stems are angled in cross-section but lack wings. Leaves are absent but the large, ovate to arrowhead-shaped stipules measure 1-4 cm long and are leaf-like. The stems and stipules are glabrous and unbranched, prehensile tendrils extend beyond the stipules from the axils.

Flowers are typically solitary (occasionally in pairs) and are lemon-yellow in color, measuring from 10-14 mm long. The banner is about 1.5 times as long as the calyx. The wings and keel are roughly equal in length to the banner. The calyx measures 7-10 mm long with linear to narrowly oblong-lanceolate teeth about twice as long as the calyx tube. The pods measure 2-4 cm long and 3-5 mm wide.


Habitat:

Yellow vetchling may be found in disturbed locations such as along roads, waste areas, gravel quarries and fallow fields.


Range:

A native of Europe, yellow vetchling may generally be found west of the Cascade Mt. crest in the Willamette and Umpqua Valleys of Oregon as well as west of the Cascades and Sierra Nevada in California.


Paul Slichter