A much-branched shrub, with ash-gray bark. Leaves. - Alternate, oblong, smooth, on slender leaf-stalks. Flowers. - White, some perfect, others unisexual; solitary or clustered in the axils of the leaves on long, slender flower-stalks. Calyx. - Minute or obsolete. Corolla. - Of four or five spreading petals. Stamens. - Four or five. Pistil. - One. Fruit. - Coral-red, berry-like.

The flowers of this shrub appear in the damp woods of May. Its light red berries on their slender stalks are noticed in late summer when its near relation, the black alder or winterberry is also conspicuous. Its generic name signifies flower with a thread-like stalk.