Large-leaf avens is a perennial with several basal leaves in a rosette and erect or ascending stems with several leaflets. The stems may rise from 30-70 cm in height. The leaves are compound pinnate or cleft into the middle vein with 9-23 irregularly shaped leaflets or lobes, the largest being the terminal one. The basal leaves may be as much as 30 cm long and the margins are toothed. 2-5 leaves may be found on the stems. These are compound ternate (3 leaflets) with irregularly toothed margins.
The inflorescence is an asymmetrical cyme of several flowers. The 5 green sepals are reflexed downward, each approximately 4-5 mm long. The 5 petals are a medium yellow (not shiny as with buttercups)and 4-6 mm long. The green, maturing fruits look like rounded pincushions with many "pins" poking out.
Large-leaf avens is found in moist woods or meadows, or along streams from the sea level to subalpine habitats.
Large-leaf avens may be found from Alaska south to Baja California and Mexico, and east in Canada to Nova Scotia.
In the Columbia River Gorge it may be found between the elevations of 100'-2400' from the western entrance to the gorge to as far east as Lyle, WA.
