Species Profile- Japanese Knotweed (Fallopia japonica) Japanese Knotweed Japanese Knotweed USDA Plant Profiles Japanese Knotweed Japanese Knotweed National Invasive Species Information Center Japanese knotweed Japanese Knotweed Japanese knotweed Japanese Knotweed Japanese Knotweed “USDA weed profile for Japanese knotweed” http://www.invasivespeciesinfo.gov/plants/knotweed.shtml Japanese Knotweed Japanese Knotweed USDA Plant Profiles Japanese Knotweed Japanese Knotweed invasive species to haunt the United States