Bitter Dock

Bitter Dock
Bitter Dock. Rumex obtusifolius.
Polygonaceae, the buckwheat, smartweed, or knotweed family.

Plant: Erect, branching plant, 1' to 4' high, bearing a branching, spike-like cluster of tiny green or pinkish flowers above slightly wavy leaves. Perennial.
Flowers: Tiny, green to pinkish flowers about 1/6", forming a branching, spike-like raceme at the top of the plant. Individual florets have a three-fold symmetry technically consisting of six sepals in two ranks, and no petals.
Leaves: Basal and alternate, broadly to narrowly ovate, to 10" long, with somewhat wavy (undulate) margins. The base of the leaf is rounded to heart-shaped, in contrast to curly dock, which has a tapered base. The leaves sometimes have reddish veins.
Fruit: Small seeds enclosed by three dark brown "wings" borne in a prominent branching, dark-brown cluster that remains standing well after the leaves have withered. Flowers produce a single valve with a seed, in contrast to curly dock, where the flowers produce three valves.
Blooming: June-September
Habitat: Moist, weedy areas, clearings and margins.

Comments: This member of the buckwheat family is introduced from Europe and is often a troublesome weed. It is similar to curly dock, but differs in having broader, less wavy leaves with a rounded or heart-shaped base, and seeds borne on single valves rather than in threes. Unlike curly dock, the leaves are not reputed to be edible, and are supposedly slightly toxic, and the sap irritating.

Where to find it: Not common in the park. I have found it along the east boundary of the park adjacent to the woods that border the Medical Center Parking lot.