"Over a couple of years, the growth got visibly weaker." Homeowner met with urgent warnings after spotting mystery plant in ...

Japanese knotweed, a terrestrial herbaceous plant that is in the Polygonaceae family, invades along rivers, streams, roads, and in disturbed areas or where dumped. It prefers full sun and rich soils ...

Native to Asia, knotweeds were introduced to North America as an ornamental plant. They can spread into natural areas growing quickly and forming dense monocultures, reducing habitat diversity, ...