Japanese Knotweed is a robust perennial with bamboo-like stems and heart-shaped leaves. It is highly invasive and can grow through concrete, causing damage to infrastructure. It spreads rapidly, forming dense thickets that outcompete native plants.
Habitat
Commonly found in disturbed areas, roadsides, and riverbanks.
Diet
Its flowers attract bees and other pollinators.
How common
Common
Best time to see a Japanese Knotweed
The best time to see a Japanese Knotweed is April–August, when about 68% of U.S. sightings happen, based on 35,820 research-grade iNaturalist observations.
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