Japanese knotweed "Japanese Bamboo"
Description:
A large bushy plant with
spreading clusters of greenish-white flowers on large, hollow, jointed,
mottled stems in leaf axils; male and female flowers on separate plants.
Flowers:
About 1/8" long;
sepals mostly 5; petals absent; cluster 2-3" long.
4-6" long, rounded
or ovate, tapering to a point, straight across at base.
Fruit:
Seed-like, black, smooth,
3-sided.
Height:
3-7'.
Flowering:
August- September.
Habitat:
Waste places and roadsides.
Comments:
This introduction from
Asia is recognizable by the stout, bushy, branched, jointed, bamboo-like
stems. Once established it can rapidly take over a given area and is quite
difficult to eradicate. In the Pacific coastal states and Virginia it
is considered a noxious weed. Its young shoots can be cooked and eaten
like asparagus, and the seeds are eaten by ground-feeding songbirds. The
similar, robust Giant Knotweed (P.sachalinese) has leaves that are heart-shaped
at the base; also from Asia, it is naturalized in some places in the East.