Abstract:
Japanese and giant knotweeds were introduced to North
America in the late 1800s as ornamentals but soon escaped into
the wild. They are particularly invasive along streams, roadsides, and
waste areas. Large, spreading patches of knotweed can completely
dominate and displace native species in open sunlight. Erosion
can increase on riverbanks or floodplains invaded by knotweed when
above ground parts die back and wash away each winter, leaving bare soil. Knotweed thrives in a variety of
habitats but is most prolific and invasive in moist, open areas.
