Stems. - Two to three feet high, glandular, more or less hairy. Leaves. - Heart-shaped, with short, rounded lobes, wavy-toothed, mostly from the root. Flowers. - Greenish or purplish, in long narrow clusters. Calyx. - Bell-shaped, broad, five-cleft. Corolla. - Of five small petals. Stamens. - Five. Pistil. - One, with two slender styles.

In May the slender clusters of the alum-root are found in the rocky woods.