Plantain-leaf buttercup as seen in a ditch along Forest Road #1647 in southeastern Logan Valley, Malheur National Forest.........June 3, 2011.
Plantain-leaf buttercup is a small to fairly large buttercup of wet places with one to several erect, sometimes hollow stems from 15-60 cm long. The thick stems range from 3.5-8 mm in diameter and do not root at the nodes, and they may also be branched within the inflorescence. The leaves are both basal and found on the stems. The basal leaves have moderately thick petioles (up to 3 mm wide) with blades up to 15 cm long and from 1-2.5 cm wide. The stem leaves are short-petiolate or sessile, but with blades similar in shape to the basal leaves. The stem leaves may be opposite or alternate.
The one to numerous flowers are found on the upper stems. The flower peidicels may be up to 15 cm long when in fruit. The 5 sepals are greenish and somewhat hairy, ranging from 3-5 mm long. The 5 petals are yellow and 5-10 mm long. The stamens number from 25-90 while the smooth pistils number 10-60 with straight stylar beaks.
Plantain-leaf buttercup is found in swales and pond margins, along streambanks or in moist alpine meadows.
Plantain-leaf buttercup is widespread in distribution throughout the western United States, and southwestern Canada.