USDA and NRCS Identifier NRCS Logo Web Site PLANTS photo banner
PLANTS Home about PLANTS PLANTS Team Partners of PLANTS What's New at PLANTS National Plant Data Team Web Site Help using PLANTS Contact PLANTS
 Search the PLANTS Web site
 Name Search

PLANTS Image Gallery
Download PLANTS data
Related tools
You are here: Home / Plant Profile

Polygonum lapathifolium L.
curlytop knotweed

General Information
Symbol: POLA4
Group: Dicot
Family: Polygonaceae
Duration: Annual
Growth Habit: Forb/herb
Native Status: AK   I
GL   I
L48   N
Data Source and Documentation
Plants-NRCS Logos
green round image for nativity Native blue round image for introduced Introduced ocre round image for introduced and nativity Both white round image for no status Absent/Unreported
image for native, but no county data Native, No County Data image for introduced, but no county data Introduced, No County Data both introduced and native, but no county data Both, No County Data
Native Status:
lower 48 status L48    Alaska status AK    Hawaii status HI    Puerto Rico status PR    Virgin Islands status VI    Navassa Island NAV    Canada status CAN    Greenland status GL    Saint Pierre and Michelon status SPM    North America NA   


click on a thumbnail to view an image, or see all the Polygonum thumbnails at the Plants Gallery

Robert H. Mohlenbrock. USDA NRCS. 1992. Western wetland flora: Field office guide to plant species. West Region, Sacramento. Provided by USDA NRCS Wetland Science Institute (WSI). Usage Requirements.

©Lawrence S. Gilliam. United States, NC, Guilford Co., damp meadow. September 12, 2004. Usage Requirements.

©Lawrence S. Gilliam. United States, NC, Guilford Co., damp meadow. September 12, 2004. Usage Requirements.

©Lawrence S. Gilliam. United States, NC, Guilford Co., damp meadow. September 12, 2004. Usage Requirements.

Britton, N.L., and A. Brown. 1913. An illustrated flora of the northern United States, Canada and the British Possessions. 3 vols. Charles Scribner's Sons, New York. Vol. 1: 666. Provided by Kentucky Native Plant Society. Scanned by Omnitek Inc. Usage Requirements.

USDA NRCS. Wetland flora: Field office illustrated guide to plant species. USDA Natural Resources Conservation Service. Provided by NRCS National Wetland Team. Usage Requirements.



Symbol Scientific Name
PEIN11 Persicaria incarnata (Elliott) Small
PELA22 Persicaria lapathifolia (L.) Gray
PETO5 Persicaria tomentosa (Schrank) E.P. Bicknell
POIN22 Polygonum incanum F.W. Schmidt
POIN19 Polygonum incarnatum Elliott
POLAP Polygonum lapathifolium L. ssp. pallidum (With.) Fr.
POLAI Polygonum lapathifolium L. var. incanum (F.W. Schmidt) W.D.J. Koch
POLAN2 Polygonum lapathifolium L. var. nodosum (Pers.) Small
POLAO Polygonum lapathifolium L. var. ovatum A. Braun
POLAP2 Polygonum lapathifolium L. var. prostratum Wimm.
POLAS Polygonum lapathifolium L. var. salicifolium Sibth.
PONO5 Polygonum nodosum Pers.
POON Polygonum oneillii Brenckle
POPEO2 Polygonum pensylvanicum L. ssp. oneillii (Brenckle) Hultén
POSC15 Polygonum scabrum Moench
POTO3 Polygonum tomentosum Schrank


Click on a scientific name below to expand it in the PLANTS Classification Report.
Rank Scientific Name and Common Name
Kingdom Plantae – Plants
Subkingdom Tracheobionta – Vascular plants
Superdivision Spermatophyta – Seed plants
Division Magnoliophyta – Flowering plants
Class Magnoliopsida – Dicotyledons
Subclass Caryophyllidae
Order Polygonales
Family Polygonaceae – Buckwheat family
Genus Polygonum L. – knotweed
Species Polygonum lapathifolium L. – curlytop knotweed

Subordinate Taxa

This plant has no children

Legal Status

U.S. Weed Information
Polygonum lapathifolium
curltop ladysthumb
curlytop knotweed
pale smartweed
This plant can be weedy or invasive according to the authoritative sources noted below.This plant may be known by one or more common names in different places, and some are listed above. Click on an acronym to view each weed list, or click here for a composite list of Weeds of the U.S.
NE&GP Stubbendieck, J., G.Y. Friisoe,and M.R. Bolick. 1994. Weeds of Nebraska and the Great Plains. Nebraska Department of Agriculture, Bureau of Plant Industry. Lincoln, Nebraska.
SWSS Southern Weed Science Society. 1998. Weeds of the United States and Canada. CD-ROM. Southern Weed Science Society. Champaign, Illinois.
WSWS Whitson, T.D. (ed.) et al.. 1996. Weeds of the West. Western Society of Weed Science in cooperation with Cooperative Extension Services, University of Wyoming. Laramie, Wyoming.

Wetland Status

Interpreting Wetland Status


PELA22  Persicaria lapathifolia (L.) Gray

North America
Great Plains OBL
Alaska FAC
Western Mountains, Valleys, and Coast FACW
Midwest FACW
Arid West FACW
Northcentral & Northeast FACW
Atlantic and Gulf Coastal Plain FACW
Eastern Mountains and Piedmont FACW



Source Large Mammals Small Mammals Water Birds Terrestrial Birds


Source Large Mammals Small Mammals Water Birds Terrestrial Birds

Description of Values

Value Class Food Cover