Lathyrus lanszwertii aka Nevada Vetchling

Lathyrus lanszwertii is a perennial in the pea family, Fabaceae. Common names include thickleaf and aspen peavine. Its native range runs from southwestern Canada to northern Mexico. It grows across much of the western United States. Records include Washington, Oregon, California, Idaho, Montana, Nevada, and Wyoming. Its range also includes Utah, Colorado, Arizona, New Mexico, and Texas. It is a plant of temperate regions. Wild plants grow on dry slopes at higher elevations. The cited habitat lies around 3,940–6,400 feet [1,200–1,950 metres] above sea level.

This herbaceous plant has stems that stand upright or clamber. Tendrils help the stems grip nearby plants for support. PFAF gives a garden size of about 1.6 feet [0.5 metres] tall. It lists a spread of about 1 foot [0.3 metres]. A broader description gives heights of 0.7–2.6 feet [0.2–0.8 metres]. That range includes plants taller than the stated garden size. The supplied species account gives no leaf or flower details. It does state that insects pollinate the flowers. No flowering season is given.

Grow this peavine in an open site without shade. PFAF lists sandy, loamy, and clay soils as suitable. Good drainage matters across these soil types. The plant accepts mildly acid, neutral, and mildly alkaline ground. It can grow in dry soil or moist soil. These preferences fit a range of drained garden settings. PFAF lists USDA hardiness zones 5–9 for the species. It also describes the plant as not frost tender. The evidence gives no species-specific pest or disease problems.

Root bacteria form nodules and help the plant obtain nitrogen. The bacteria take this nitrogen from the air. The plant uses some of it for its own growth. Nearby plants may also gain from this process. PFAF lists nitrogen fixation among the plant’s useful traits. Its tendrils allow it to use surrounding vegetation as support. The source does not flag it as weedy.

PFAF advises soaking seeds in warm water for 24 hours. Sow them in a cold frame in early spring. Move seedlings into separate pots once large enough to handle. Plant them out in summer. PFAF lists no known medicinal use. Its detailed food accounts concern a named variety, not this species alone. Those accounts cannot establish edible parts for the whole species. The source also lacks a confirmed species-specific toxicity record.