Kebnat

Reynoutria

3 species

In Québec, the genus Reynoutria (family Polygonaceae) counts 3 species of plants. The stars? Japanese knotweed, Giant knotweed and Dwarf Japanese knotweed, the most often observed. The richest region: Chaudière-Appalaches, with 3 species. Every species has its own page: photos, its season, its habitat and the best places to see it near you.

Species observed by region

Where do the observations come from?

  • Mostly iNaturalist : photos taken by people all over Québec, with the species confirmed by the community.
  • Other public sources : such as eBird for birds and the provincial forest inventories, gathered by GBIF, the global biodiversity data network.
  • What we keep : confirmed observations, with an exact position (not blurred to protect a rare species), that their author allows to be reused.
  • One place counts once : several observations of the same species at the same spot (within 11 m) count as one.
  • So our numbers are lower : than iNaturalist’s total. A region without observations does not mean the species does not live there.

Data downloaded in September 2026.

  1. Chaudière-Appalaches3
  2. Bas-Saint-Laurent2
  3. Capitale-Nationale2
  4. Mauricie2
  5. Estrie2
  6. Montréal2
  7. Abitibi-Témiscamingue2
  8. Gaspésie–Îles-de-la-Madeleine2
  9. Lanaudière2
  10. Montérégie2
  11. Saguenay–Lac-Saint-Jean1
  12. Outaouais1
  13. Côte-Nord1
  14. Laval1
  15. Laurentides1
  16. Centre-du-Québec1

Reynoutria 3

Caryophyllales
All2,855Poales529Asterales316Lamiales214Rosales205Caryophyllales204Malpighiales120Asparagales119Brassicales109Ranunculales98Ericales95Fabales91Alismatales74Saxifragales68Polypodiales60Apiales51Dipsacales50Gentianales50Solanales43Fagales38Boraginales33Malvales29Myrtales29Sapindales27Pinales26Liliales22Ophioglossales20Lycopodiales18Geraniales17Cornales14Celastrales12Equisetales9Vitales7Commelinales6Cucurbitales6Nymphaeales5Oxalidales5Piperales5Osmundales4Aquifoliales3Santalales3Selaginellales3Acorales2Buxales2Ceratophyllales2Isoetales2Salviniales2Crossosomatales1Ginkgoales1Hymenophyllales1Laurales1Magnoliales1Marchantiales1Proteales1Schizaeales1
Polygonaceae
All204Caryophyllaceae78Polygonaceae55Amaranthaceae51Droseraceae4Montiaceae3Nyctaginaceae3Phytolaccaceae2Plumbaginaceae2Portulacaceae2Basellaceae1Molluginaceae1Talinaceae1Tamaricaceae1
Japanese knotweed1,523 observations
Giant knotweed89 observations
Dwarf Japanese knotweed1 observations