Calflora
Taxon  Report   10891 
Fallopia japonica  (Houtt.) Ronse Decr.
Japanese knotweed
Fallopia japonica
© 2005 Louis-M. Landry
More photos from
CalPhotos / Calflora
Fallopia japonica
© 2011 Louis-M. Landry
Fallopia japonica, a dicot, is a perennial herb that is not native to California. Cal-IPC rating: Moderate

Interactive Distribution Map


Observation Hotline
(observation details + photos)



point, line, or polygon

one or more occurrences
within a 7.5-minute quadrangle

Plant Characteristics
and Associations



Bloom Period
Fallopia japonica
© 2006 Dr. Amadej Trnkoczy
Family: POLYGONACEAE  
Genus: Fallopia
Community:
escaped cultivar
Wetlands: Occurs usually in non wetlands, occasionally in wetlands
Name Status:
Accepted by JEF
PLANTS accepted name: Polygonum cuspidatum
Alternate Names:
(according to)

ICPN: Polygonum cuspidatum
ICPN: Reynoutria japonica
ICPN: Fallopia japonica var. japonica
More information about  Fallopia japonica
Photos on CalPhotos / Google Images
Photos on PlantID.net

Jepson eFlora

Records from the Consortium of California Herbaria

USDA PLANTS Profile (POCU6)

Search efloras.org (Flora of North America)

website references from Google


Suggested Citation
Calflora: Information on California plants for education, research and conservation,
with data contributed by public and private institutions and individuals, including the Consortium of California Herbaria.
[web application]. 2018. Berkeley, California: The Calflora Database [a non-profit organization].
Available: http://www.calflora.org/   (Accessed: Jun 24, 2018).

The information on this page comes from diverse sources. None of the links are sponsored.