Thalictrum revolutum

Native

Dry. Prairies, thickets, open woods. Full to partial sun.

June to July

Whitish

3′ to 7′

This is a 3′ to 7′ tall, erect, perennial, foul-smelling forb that rises from rhizomes. Staminate flowers (male) and pistillate flowers (female) are borne on separate plants. It often forms colonies.

Stems are erect, stout, hairless, and covered with a whitish, waxy coating (glaucous). They are occasionally branched in the upper half. They are green when young becoming reddish purple with maturity.

The leaves are alternate. Lower stem leaves are on leaf stalks, middle and upper leaves are stalkless. They are 3 or 4 times ternate—divided into 3 main divisions (ternate), each division further divided into 3 segments (biternate), each segment further divided into 3 leaflets (triternate), or once more divided. The leaflets are leathery, variable in shape, ⅓″ to 2⅓″ long, ¼″ to 2″ wide, 1 to 5 times, but usually no more than 2¾ times, as long as wide. The larger leaflets are divided into 2 to 5 but usually 2 or 3 lobes. The lobes are untoothed or occasionally have a few additional teeth. Smaller leaflets may be unlobed. The margins are rolled backward toward the underside. The upper surface is hairless. The lower surface is covered with whitish glandular hairs making it whitish and waxy in appearance, and has a network of conspicuous, prominent (raised) veins. When crushed the stems and leaves produce a skunk-like smell.

The male inflorescence is a large, open, showy, branched cluster at the end of the stems and branches. It is up to 2′ tall and 1′ wide.

Male flowers have usually 4 but up to 6 whitish petal-like sepals. There are no petals. They droop at the end of short stalks. The sepals often drop off early leaving about 12 stamens with white filaments and yellow anthers. The flowers do not produce petals or nectar to attract insects. They are wind pollinated.

The fruit is an achene a little over ⅛″ long.

Tall meadow rue (Thalictrum dasycarpum) has hairy but not glandular lower leaf surfaces. The foliage is not skunk-scented.

Early meadow rue (Thalictrum doicum) is a much smaller plant, 12″ to 28″ at maturity. All leaves, including middle and upper leaves, are on long stalks. The leaflets have 3 to 12 often round-toothed lobes. The flowers bloom earlier, April to May. It is found in woodlands, not prairies.