Urtica dioica ssp. gracilis

Native

Wet to dry. Disturbed sites.

June to September

Cream

18″ to 72″

This is a 18″ to 72″ tall, erect, perennial forb that rises from a long rhizome. It often forms large colonies or dense patches.

The stems are erect, stout, unbranched, and 4-angled. They are hairless or have straight, stiff, sharp, appressed hairs, with a few stinging hairs.

The leaves are opposite, egg-shaped to lance-shaped, 2⅓″ to 8″ long, and ¾″ to 3″ wide. The blades are rounded, rarely heart-shaped, at the base, and taper to a point at the tip. The upper surface is hairless or has minute, fine, short hairs, but rarely has a few stinging hairs. The lower surface has stinging hairs. The margins are coarsely toothed, the teeth averaging 1 ⁄16″ to ⅛″ deep. The leaves droop downward slightly on ½″ to 2½″ long stalks that have stinging hairs. At the base of each leaf stalk are a pair of 3 ⁄16″ to ⅝″ long, lance-shaped, leaf-like appendages (stipules).

The inflorescences are branched, spreading. elongated clusters drooping downward on stalks rising from the middle and upper leaf axils.

Individual flowers have either male or female reproductive parts, but not both (unisexual). Both male (with stamens) and female (with pistils) flowers are borne on all plants with the female flowers above the male flowers.

Male flowers are ascending, ⅛″ wide, with 4 green petal-like sepals and 4 white stamens. There are no petals. Female flowers are loose and bent backward, ⅛″ wide, with 2 inner, egg-shaped sepals enclosing the ovary, and 2 outer, linear, narrowly spoon-shaped, or lance-shaped, petal-like sepals. There are no petals.

The fruit is an egg-shaped achene.

Canadian woodnettle (Laportea canadensis) leaves are alternate and broader. The stem zigzags.

Small-spike false nettle (Boehmeria cylindrica) has no stinging hairs.

The stinging hairs are hollow and act like syringes injecting histamine, acetylcholine, and a neurotoxin. They produce an intense burning and itching sensation.