blue cohosh

not listed

N4N5 - Apparently Secure to Secure

SNR - Unranked

not listed

Blue cohosh is a 1′ to 3′ tall, erect, perennial forb that rises on multiple stems from a rhizome.

The stems are erect, hairless, and unbranched. They bear just 2 leaves, the first just above the middle, the second just below the inflorescence.

The first leaf is compound, triternate, and stalkless. It divides at the base into 3 long stalks. Each stalk is again divided into 3 shorter stalks. At the end of each of these shorter stalks are 3 leaflets. The overall appearance is of 3 biternate leaves. The 27 leaflets are broad, inversely egg-shaped, 2″ to 3″ long, and ¾″ to 4″ wide. They are usually 2- to 5-lobed near the tip, but they may be unlobed. When young they are covered with a whitish, waxy coating. The margins are untoothed. The upper and lower surfaces are hairless. The second leaf is similar to the first but smaller.

The inflorescence is a small, branched cluster of 5 to 70 flowers at the end of the stem.

The flowers are ⅜″ to ½″ wide. There are 3 or 4 sepal-like bracts that drop early. There are 6 petal-like, yellowish green, widely spreading sepals. The 6 petals are reduced to gland-like nectaries, are opposite the sepals, and are much shorter than the sepals. In the center of the flower are 6 stamens with yellow anthers surrounding a green ovary.

The fruits never develop. Two large growing seeds rupture the ovary. The seeds are borne naked in pairs on short stems at the end of the elongated pedicel above the leaves. The seeds are have a dark blue, fleshy seed coat. The seed coat is covered with a whitish, waxy coating, making the seed appear light blue.

1′ to 3′

Yellowish green

May-apple (Podophyllum peltatum) leaves are not compound. The flower droops from the axil of two leaves. The fruit is a yellow berry.

Twinleaf (Jeffersonia diphylla) leaves are divided into 2 kidney-shaped segments. The flowers are borne on a leafless flower stalk. The fruit is brownish and capsule-like.

Moist. Woods.

April to May

Sources

2, 3, 4, 5, 7, 28, 29, 30.

Native

Common

Plant

Inflorescence

Leaves

Infructescence