Links
Alien Plant Working Group - Japanese knotweed - photos, North American distribution, links
Invasive.org - Invasive and Exotic Species of North America - Japanese knotweed - photos, North American distribution, links
Invasive.org - Invasive and Exotic Species of North America - Biological Control of Japanese knotweed
ME - University of Maine Cooperative Extension - Japanese Knotweed/Mexican Bamboo - fact sheet and photo (HTML or PDF)
Minnesota Department of Natural Resources - Japanese Knotweed - fact sheet with photos
New England - Invasive Plant Atlas of New England - Polygonum cuspidatum (Japanese knotweed) - fact sheet and photos
New England - Invasive Plant Atlas of New England - Polygonum sachalinense (Giant or Sakhalin knotweed) - fact sheet and photos
NY - Invasive Plant Council of New York State - Japanese Knotweed - fact sheet with photos
Oregon State University Horticulture - knotweed and other invasives for landscaping in Oregon
Southeast Exotic Pest Plant Council - Invasive Plant Manual: Japanese Knotweed
UK - Japanese Knotweed Alliance - Japanese Knotweed - detailed fact sheet with photos
USDA Forest Service - Pest Alert: Japanese Knotweed - brief information, photos, US map
USDA - National Agricultural Library - Species Profile: Japanese Knotweed - photo, numerous links
USDA PLANTS Database - PLANTS Profile - Polygonum cuspidatum - characteristics, photo, US distribution
USDA PLANTS Database - PLANTS Profile - Polygonum sachalinense - characteristics, photo, US distribution
USDA PLANTS Database - PLANTS Profile - Polygonum x bohemicum - characteristics, photo, US distribution
Virginia Natural Heritage Program - Japanese Knotweed - fact sheet (PDF)
WA - Clark County Weed Documents - Efficacy Trial Documents & Findings for Knotweed - links to detailed control information and photos (PDF)
Washington State Department of Ecology - Technical Information about Polygonum cuspidatum (Japanese Knotweed) - - Fact sheet and photos (PDF)
WI - Freckmann Herbarium, UW-Stevens Point - Polygonum cuspidatum - species characteristics, photos, WI distribution
WI - Freckmann Herbarium, UW-Stevens Point - Polygonum sachalinense - species characteristics, photos, WI distribution
WI - Freckmann Herbarium, UW-Stevens Point - Polygonum x bohemicum - species characteristics, photos, WI distribution
Wisconsin State Herbarium: Wisconsin Vascular Plants - Polygonum cuspidatum - characteristics, photos, WI distribution
Wisconsin State Herbarium: Wisconsin Vascular Plants - Polygonum sachalinense - characteristics, photos, WI distribution
Wisconsin State Herbarium: Wisconsin Vascular Plants - Polygonum x bohemicum - characteristics, WI distribution