Virginia Knotweed

Virginia Knotweed
Virginia Knotweed. Polygonum virginianum, also Persicaria virginiana.
Polygonaceae, the buckwheat, smartweed or knotweed family.

Plant: Erect to ascending plant 1'-4', with long, arching spikes extending far beyond the leaves, sparsely studded with tiny white flowers. Perennial.
Flowers: Tiny, white, < 1/4" long, with four petal-like sepals. Petals are absent. Flowers are sparsely spaced, often bending backwards, on long, arching spikes that may extend 2'.
Leaves: Alternate, ovate, 2"-6", with short petioles and smooth margins. Sheath where leaf emerges is fringed and hairy.
Blooming: July-September
Habitat: Woods and thickets.

Comments: This native member of the buckwheat family has recently been placed in the separate genus Persicaria by some authorities, along with most of the other common smartweeds.

Where to find it: There is a large patch in the woods by the parking lot.