Lathyrus graminifolius is most easily identified by the compound leaves with long filiform leaflets. The flowers are pink marked with purple, and turn orange as they age. Lathyrus graminifolius is found at upper middle to upper elevations in the Gila National Forest. Lathyrus and Vicia are two genera that can be difficult to tell apart without using a loupe to examine the style. If one carefully removes the petals and the stamens so that just the stigma remains, the difference becomes obvious. In Lathyrus, the style is hairy up and down an entire side, whereas in Vicia there is just a tuft of hairs below the apex.
Kearney and Peebles 1969, Martin and Hutchins 1980
Duration: Perennial Nativity: Native Lifeform: Vine General: Herbaceous perennial, stems erect or weakly climbing, stems commonly with tendrils at the tips, to 60 cm long. Leaves: Pinnate, 6-10 leaflets, with large stipules, leaflets 20-40 mm long, rarely more than 5 mm wide. Flowers: Purple or blue, less than 12-16 mm long, in axillary racemes, styles hairy along the inner edge. Fruits: Pods dehiscent, narrow, flat, two-valved, 4-6 cm long, glabrous. Ecology: Found in pine forests from 4,000-9,000 ft (1219-2743 m); flowering April-September. Notes: The leaflets of Lathyrus are generally larger, thicker, and more prominently veined than the similar-looking Vicia. This genus contains the sweet-pea. Ethnobotany: Tender plants eaten as green in the spring. Synonyms: Lathyrus palustris var. angustifolius, Linnaeus palustris var. graminifolius, Linnaeus palustris var. nudicaulis, Orobus dissitifolius Editor: LCrumbacher, 2011 Etymology: Lathyrus comes from the Greek lathyros, an old name for "pea", while graminifolius means with foliage like grass.