Flower:

The flowers are 1/3 to ½ inch across, each on a 1 to 3-inch densely hairy stalk, in a loose cluster of 1 to 3 flowers at tips of branching stems and upper leaf axils, typically one flower opening at a time. Petals are white, oval to egg shaped, less than ¼ inch long, alternating between the larger green, sharply triangular sepals behind them. The flower center is a conspicuous round swirl of thick, hair-like green styles, ringed by creamy tipped stamens that quickly turn brown. Flowers nod down when first opening turning upward as the stalk elongates and the seedhead matures.

Leaves and stems:

Leaves can be highly variable. The primary basal leaves are pinnately compound and long stalked, fiddle shaped in outline, up to 6 inches long and 3 inches wide, the wedge-shaped leaflets widely spaced along central stalk and further deeply cleft into narrow segments with coarsely lobed edges, and pale on the underside from silvery hairs. Stem leaves are alternate, the lower with fewer and broader leaflets, 3 to 5 crowded towards the tip and coarsely toothed; some with a large, round or shallowly lobed end leaflet and a few small lateral leaflets. Upper stem leaves are smaller and stalkless with three palmately compound leaflets, or a 3-lobed simple leaf. Stems are single or several, densely covered with stiff hairs throughout, mostly unbranched or few branches in the upper plant.

Fruit:

Fruit is an upright, bristly ball about ¾ inch in diameter, each seed (achene) is tipped by the dried style that has a hook at the tip.

Notes:

On the NW edge of its North American range, Rough Avens is not frequently encountered in Minnesota and is listed by the Minnesota DNR as a tracked species. Except for a handful of earlier records, most of what is known about its distribution and habitat in this state are from collections made since the early 1980s. A moisture lover, it appears to tolerate a range of light conditions from open wet meadows and stream banks to deep deciduous woods and shady ravines. In our botanizing we've encountered it twice, both of which would be new MN county records, but too early or late in the season to catch it flowering. One is in a deep mucky seep at Battle Creek Regional Park in Ramsey County and another in a wet quarry bottom in Banning State Park, Pine County.