Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Datasheet

Persicaria punctata
(dotted smartweed)

Toolbox

Datasheet

Persicaria punctata (dotted smartweed)

Summary

  • Last modified
  • 13 July 2018
  • Datasheet Type(s)
  • Invasive Species
  • Preferred Scientific Name
  • Persicaria punctata
  • Preferred Common Name
  • dotted smartweed
  • Taxonomic Tree
  • Domain: Eukaryota
  •   Kingdom: Plantae
  •     Phylum: Spermatophyta
  •       Subphylum: Angiospermae
  •         Class: Dicotyledonae
  • Summary of Invasiveness
  • P. persicaria is a species of knotweed native to the Americas. It has been introduced, presumably accidentally, to New Zealand, Pakistan and Hawaii, where it is found in shallow water, shores, marshes, swamps,...

  • There are no pictures available for this datasheet

    If you can supply pictures for this datasheet please contact:

    Compendia
    CAB International
    Wallingford
    Oxfordshire
    OX10 8DE
    UK
    compend@cabi.org
  • Distribution map More information

Don't need the entire report?

Generate a print friendly version containing only the sections you need.

Generate report

Identity

Top of page

Preferred Scientific Name

  • Persicaria punctata (Elliott) Small

Preferred Common Name

  • dotted smartweed

Other Scientific Names

  • Persicaria persicarioides (Kunth) Small
  • Persicaria punctate var. eciliata Small
  • Polygonum acre Kunth
  • Polygonum epilobioides Wedd.
  • Polygonum punctatum Elliot
  • Polygonum punctatum var. aquatile (Mart.) Fassett
  • Polygonum punctatum var. confertiflorum (Meisn.) Fassett
  • Polygonum punctatum var. ellipticum Fassett
  • Polygonum punctatum var. leptostachyum (Meisn.) Small
  • Polygonum punctatum var. parviflorum Fassett
  • Polygonum punctatum var. parvum Vict. & J. Rousseau
  • Polygonum punctatum var. punctatum Elliott

Local Common Names

  • : ananash; barbasco; hierba del bicho; padilla; yerba caiman; yerba de sap
  • : arse-smart; tar-weed; turkey-troop; water smartweed
  • : piment-vache; renouee ponctuee
  • Brazil: erva-de-bicho-pontuada

Summary of Invasiveness

Top of page

P. persicaria is a species of knotweed native to the Americas. It has been introduced, presumably accidentally, to New Zealand, Pakistan and Hawaii, where it is found in shallow water, shores, marshes, swamps, the borders of ponds and small streams, drainage ditches and floodplain forests.

Taxonomic Tree

Top of page
  • Domain: Eukaryota
  •     Kingdom: Plantae
  •         Phylum: Spermatophyta
  •             Subphylum: Angiospermae
  •                 Class: Dicotyledonae
  •                     Order: Polygonales
  •                         Family: Polygonaceae
  •                             Genus: Persicaria
  •                                 Species: Persicaria punctata

Notes on Taxonomy and Nomenclature

Top of page

Missouri Botanical Garden (2014) listed three varieties: Persicaria punctata var. robustior (Small) Small, Persicaria punctata var. eciliata Small and Persicaria punctata var. tacubayana Nieuwl.

Fassett (1949) proposed a complicated classification for Persicaria punctata comprising 12 varieties in North and South America. He also identified numerous specimens that he considered to be morphologically intermediate between various varieties. Dalci (1972, cited in Flora of North America, 2013) documented a wide range of phenotypic and genotypic variation throughout the range of P. punctata and extensive overlap in many of the features used by Fassett to distinguish varieties. Consequently, recognition of varieties does not seem warranted (Flora of North America, 2013).

Description

Top of page

Slightly modified from Flora of North America (2013):

Plants are annual or perennial, 15-120 cm; roots also often arising from proximal nodes; rhizomes often present.

Stems are ascending to erect, branched, without noticeable ribs, glabrous, glandular-punctata. 

Leaves are ochre brown, cylindric, (4-)9-18 mm, chartaceous, base inflated, margins truncate, ciliate with bristles 2-11 mm, surface glabrous or strigose, glandular-punctata; petiole 0.1-1 cm, glandular-punctata, leaves sometimes sessile; blade without dark triangular or lunate blotch adaxially, lanceolate to lanceolate-ovate or subrhombic, 4-10(-15) by 0.6-2.4 cm, base tapered or cuneate, margins antrorsely strigose, apex acute to acuminate, faces glabrous or scabrous along midveins, glandular-punctata. 

Inflorescences are mostly terminal, sometimes also axillary, erect, interrupted, 50-200 by 4-8 mm; peduncle 30-60 mm, glabrous, glandular-punctata; ocreolae mostly not overlapping, margins mostly ciliate with bristles to 2 mm. Pedicels ascending, 1-4 mm. 

Flowers 2-6 per ocreate fascicle, homostylous; perianth greenish proximally, white distally, rarely tinged pink, glandular-punctata with punctae ± uniformly distributed, scarcely accrescent; tepals 5, connate ca. 1/ 3 their length, obovate, 3-3.5 mm, veins prominent or not, not anchor-shaped, margins entire, apex obtuse to rounded; stamens 6-8, included; anthers pink or red, elliptic to ovate; styles 2-3, connate proximally. 

Achenes included or apex exerted, brownish black, usually 3-gonous, rarely biconvex, (1.8-)2.2-3.2 by 1.5-2.2 mm, shiny, smooth.

Distribution

Top of page

P. punctata is native to most of the Americas, from Canada to Chile and including the Caribbean. It is found in all but 13 of the mainland US states and in most Canadian provinces. It is also native to many South and Central American countries. In Illinois, it is described by Illinois Wildflowers (2013) as one of the more common smartweeds in wetland areas.

P. punctata has been introduced to New Zealand, Pakistan and Hawaii, where it is found in shallow water, shores, marshes, swamps, the borders of ponds and small streams, drainage ditches and floodplain forests.

Distribution Table

Top of page

The distribution in this summary table is based on all the information available. When several references are cited, they may give conflicting information on the status. Further details may be available for individual references in the Distribution Table Details section which can be selected by going to Generate Report.

Continent/Country/RegionDistributionLast ReportedOriginFirst ReportedInvasiveReferenceNotes

Asia

ChinaPresentGBIF, 2014
IndiaPresentGBIF, 2014
IndonesiaPresentGBIF, 2014
PakistanPresent, few occurrencesIntroduced Not invasive Flora of Pakistan Editorial Committee, 2013Reported from N.W.F province from Akbarpur, B. L. Burtt 1045, 1052 (E). Seems to be a rare species.

North America

BermudaPresentNativeUSDA-ARS, 2013
CanadaPresentPresent based on regional distribution.
-British ColumbiaPresentNativeFlora of North America, 2013
-ManitobaPresentNativeFlora of North America, 2013
-New BrunswickPresentNativeFlora of North America, 2013
-Nova ScotiaPresentNativeFlora of North America, 2013
-OntarioPresentNativeFlora of North America, 2013
-Prince Edward IslandPresentNativeFlora of North America, 2013
-QuebecPresentNativeFlora of North America, 2013
-SaskatchewanPresentNativeFlora of North America, 2013
MexicoPresentNativeFlora of North America, 2013
USAPresentNativeUSDA-NRCS, 2013
-AlaskaPresentNativeFlora of North America, 2013
-ArizonaPresentNativeFlora of North America, 2013
-ArkansasPresentNativeFlora of North America, 2013
-CaliforniaPresentNativeFlora of North America, 2013
-ColoradoPresentNativeFlora of North America, 2013
-ConnecticutPresentNativeFlora of North America, 2013
-DelawarePresentNativeFlora of North America, 2013
-District of ColumbiaPresentNativeFlora of North America, 2013
-FloridaPresentNativeFlora of North America, 2013
-GeorgiaPresentNativeFlora of North America, 2013
-HawaiiPresentIntroducedFlora of North America, 2013
-IdahoPresentNativeFlora of North America, 2013
-IllinoisPresentNativeFlora of North America, 2013
-IndianaPresentNativeFlora of North America, 2013
-IowaPresentNativeFlora of North America, 2013
-KansasPresentNativeFlora of North America, 2013
-KentuckyPresentNativeFlora of North America, 2013
-LouisianaPresentNativeFlora of North America, 2013
-MainePresentNativeFlora of North America, 2013
-MarylandPresentNativeFlora of North America, 2013
-MassachusettsPresentNativeFlora of North America, 2013
-MichiganPresentNativeFlora of North America, 2013
-MinnesotaPresentNativeFlora of North America, 2013
-MississippiPresentNativeFlora of North America, 2013
-MissouriPresentNativeFlora of North America, 2013
-MontanaPresentNativeFlora of North America, 2013
-NebraskaPresentNativeFlora of North America, 2013
-New HampshirePresentNativeFlora of North America, 2013
-New JerseyPresentNativeFlora of North America, 2013
-New MexicoPresentNativeFlora of North America, 2013
-New YorkPresentNativeFlora of North America, 2013
-North CarolinaPresentNativeFlora of North America, 2013
-North DakotaPresentNativeFlora of North America, 2013
-OhioPresentNativeFlora of North America, 2013
-OklahomaPresentNativeFlora of North America, 2013
-OregonPresentNativeFlora of North America, 2013
-PennsylvaniaPresentNativeFlora of North America, 2013
-Rhode IslandPresentNativeFlora of North America, 2013
-South CarolinaPresentNativeFlora of North America, 2013
-South DakotaPresentNativeFlora of North America, 2013
-TennesseePresentNativeFlora of North America, 2013
-TexasPresentNativeFlora of North America, 2013
-VermontPresentNativeFlora of North America, 2013
-VirginiaPresentNativeFlora of North America, 2013
-WashingtonPresentNativeFlora of North America, 2013
-West VirginiaPresentNativeFlora of North America, 2013
-WisconsinPresentNativeFlora of North America, 2013
-WyomingPresentNativeFlora of North America, 2013

Central America and Caribbean

BahamasPresentNativeUSDA-ARS, 2013
BelizePresentNativeUSDA-ARS, 2013
Cayman IslandsPresentNativeUSDA-ARS, 2013
Costa RicaPresentNativeUSDA-ARS, 2013; USDA-ARS, 2013
CubaPresentNativeUSDA-ARS, 2013
El SalvadorPresentNativePIER, 2013
GuadeloupePresentNativeUSDA-ARS, 2013
GuatemalaPresentNativeFlora of North America, 2013
HondurasPresentNativePIER, 2013
JamaicaPresentNativeUSDA-ARS, 2013
MartiniquePresentNativeUSDA-ARS, 2013
NicaraguaPresentNativePIER, 2013
PanamaPresentNativePIER, 2013
Puerto RicoPresentNativeFlora of North America, 2013
Saint LuciaPresentNativeUSDA-ARS, 2013
Saint Vincent and the GrenadinesPresentNativeUSDA-ARS, 2013

South America

ArgentinaPresentNativeUSDA-ARS, 2013
BoliviaPresentNativeUSDA-ARS, 2013
BrazilPresentNativeFlora of North America, 2013
ColombiaPresentNativeUSDA-ARS, 2013
EcuadorPresentNativePIER, 2013
French GuianaPresentNativeUSDA-ARS, 2013
GuyanaPresentNativeUSDA-ARS, 2013
ParaguayPresentNativeUSDA-ARS, 2013
PeruPresentNativePIER, 2013
SurinamePresentNativeUSDA-ARS, 2013
VenezuelaPresentNativeUSDA-ARS, 2013

Oceania

New ZealandWidespreadIntroduced Invasive Webb et al., 1988

History of Introduction and Spread

Top of page

There is little or no information on how P. punctata was introduced to New Zealand and Pakistan. The first record of it in New Zealand was in 1976 (Webb et al., 1988).

Habitat

Top of page

P. punctata grows in shallow water, shores, marshes, swamps, the borders of ponds and small streams, drainage ditches and floodplain forests (Illinois Wildflowers, 2013). This plant is often found along the edge of stagnant or slow-moving water, and appears to favour degraded wetlands. It grows at altitudes of 0-1500 m above sea level (Flora of North America, 2013). In Illinois, USA, P. punctata occurring in flood-prone areas of woodlands. In New Zealand, it is found in wet places such as swamps, ditches, lakesides and streamsides (Webb et al, 2013); similarly, in Hawaii it is found ‘naturalized along streambeds, wet areas, in running or standing water, and in disturbed wet forest’ (Wagner et al., 1999, cited in PIER, 2013).

Biology and Ecology

Top of page

Little has been reported on the biology or ecology of P. punctata, but the species is similar in appearance and habitat to the cosmopolitan species P. hydropiper, whose biology may be similar.

Genetics

2n = 44 (Flora of North America, 2013).

Longevity

In North America P. punctata is described by Flora of North America (2013) as annual or perennial, but there seems to be no information on how long plants can live for.

Activity patterns

In the United States, P. punctata flowers between June and November (Flora of North America, 2013).

Population size and structure

Illinois wildflowers (2013) reported that P. persicata ‘often forms colonies of varying size in wet areas’.

Associated species

According to Illinois Wildflowers (2013), short-tongued Halictid bees, various kinds of wasps, Syrphid flies and other kinds of flies, and the occasional beetle, including ladybirds, are attracted to the nectar of P. punctata. Halictid bees also collect pollen.

 

Environmental requirements

P. punctata seems to require moist soil or even shallow standing water (Flora of North America, 2013). 

Notes on Natural Enemies

Top of page

At least in Illinois, USA, caterpillars of the butterflies Lycaena hyllus (bronze copper) and Lycaena helloides (purple copper) feed on the foliage, as do the caterpillars of several moth species and the adults of the leaf beetle Gastrophysa polygoni (Illinois Wildflowers, 2013). The same source lists the larvae of the moths Lithocodia carneola, L. synochitis, Orthonoma centrostrigaria, O. obstipata, Acronicta oblinita, Pyrrhia experimens, Dipteryia rosmani, Xanthotype sospeta, Haematopis grataria and Nomophila neararctica as herbivores that feed on the foliage of  Persicaria species.

Means of Movement and Dispersal

Top of page

Natural dispersal (non-biotic)

P. punctata has no means of vegetative spread and the seeds are not adapted for dispersal other than by floating in water.

Vector transmission (biotic)

The seeds may be transported by mud on the feet of water birds, or possibly scattered by birds feeding on the seeds.

Accidental introduction

Presumably its introductions to countries well outside its native range were accidental, so further accidental introductions are always possible. 

Impact

Top of page

In the countries to which it has been introduced P. punctata seems to have had little impact so far, and is seen simply as another the introduced weedy species in wetland areas.

Risk and Impact Factors

Top of page Invasiveness
  • Proved invasive outside its native range
  • Has a broad native range
  • Tolerant of shade
  • Fast growing
  • Has high reproductive potential
  • Has propagules that can remain viable for more than one year
  • Has high genetic variability

Uses

Top of page

Social benefit

The Chippewa, Houma, and Iroquois people of North America prepared decoctions from the leaves, flowers and roots of P. punctata for use as analgesics as well as gastrointestinal, orthopedic and psychological aids (Moerman, 1998, cited in Flora of North America, 2013).

In parts of Brazil the plant is used as a herb to treat intestinal disorders. De Almeida Alves et al. (2001) extracted the compound polygodial from aerial parts of the plant and found that it had strong fungitoxic activity. Since this compound also has antibiotic, anti-inflammatory and anti-hyperalgesic properties, it may account for the effects attributed to this species by folk medicine.

Environmental services

The seeds are eaten by many species of ducks, seed-eating rails and various songbirds, and may be a minor source of food to muskrats (Illinois Wildflowers, 2013). According to Hickman (2013), the species is planted as waterfowl food.

 

Similarities to Other Species/Conditions

Top of page

P. punctata and its close relatives P. robustior and P. glabra are unique among native North American smartweeds in possessing complex glands called valvate chambers in their epidermises.

P. punctata is confused most often with P. hydropiper (Flora of North America, 2013). Fassett (1949) noted that P. punctata shares with P. hydropiper the characteristic features of glandular dots on the perianth. However, P. punctata has smooth and shining rather than roughened and dull achenes and a strong tendency to longer internodes, less drooping spikes and less red colouring in the perianth.

Webb et al. (1988) experienced some slight difficulties with identifying the New Zealand material of P. punctata:  ‘Characters of the New Zealand plants put them closer to P. punctata than any other species, judging from descriptions in eFloras and from specimens. However, in the few American specimens examined, the fruits are smooth instead of being finely granular as in New Zealand plants, although they are more or less glossy in both cases. Otherwise, the tallness and robustness of the New Zealand plants mean that they also resemble descriptions of the American P. robustius (small) fern. Both species are related to the Old World P. hydropiper. Within New Zealand, North Island plants have deep green leaves, whereas South Island plants have yellowish green leaves, but the greater size of vegetative parts still distinguishes them all from P. hydropiper. Also, the only moderately peppery taste, the more or less tubular and appressed upper ochreae, white perianth, and obviously shining fruits usually distinguish P. punctatum from P. hydropiper.’

Prevention and Control

Top of page

Due to the variable regulations around (de)registration of pesticides, your national list of registered pesticides or relevant authority should be consulted to determine which products are legally allowed for use in your country when considering chemical control. Pesticides should always be used in a lawful manner, consistent with the product's label.

Physical/mechanical control

Individual plants of P. punctata could be pulled or dug up, but this would not be recommended for large areas.

Biological control

The caterpillars of several moth species feed on Persicaria species in its native North America (see Notes on Natural Enemies; Illinois Wildflowers, 2013). However, P. punctata has not become a serious enough weed in its introduced range to warrant biological control yet.

Chemical control

Species of Persicaria can be controlled with glyphosate, 2,4-D, aminopyralid, clopyralid, dicamba, triclopyr or imazapyr, but all these compounds will adversely affect other plant species, including desirable species (DiTomaso et al., 2013).

Gaps in Knowledge/Research Needs

Top of page

There seems to be very little published information on the biology, ecology and associated species of P. punctata. More information on longevity of plants and seeds, environmental preferences and reproduction would be very useful.

References

Top of page

Alves TMde A; Ribeiro FL; Kloos H; Zani CL, 2001. Polygodial, the fungitoxic component from the Brazilian medicinal plant Polygonum punctatum. Memórias do Instituto Oswaldo Cruz, 96(6):831-833.

Dalci M, 1972. The taxonomy of section Persicaria (Tourn. in the genus Polygonum (Tourn. (Polygonaceae) in the United States east of the Rocky Mountains. dissertation. Nebraska, USA: University of Nebraska.

DiTomaso JM; Kyser GB, 2013. Lady's thumb and pale smartweed. Weed control in natural areas in the western United States. California, USA: Weed Research and Information Centre, University of California, 544 pp. http://wric.ucdavis.edu/information/natural%20areas/wr_P/Polygonum_lapathifolium-persicaria.pdf

Fassett NC, 1949. The variation of Polygonum punctatum. Brittonia, 6(4):369-393.

Flora of North America, 2013. Flora of North America. FNA. http://www.efloras.org/flora_page.aspx?flora_id=1

Flora of Pakistan Editorial Committee, 2013. Flora of Pakistan, eFloras website. St. Louis, Missouri and Cambridge, Massachusetts, USA: Missouri Botanical Garden and Harvard University Herbaria. http://www.efloras.org/flora_page.aspx?flora_id=5

GBIF, 2015. Global Biodiversity Information Facility. http://www.gbif.org/species

Hickman JC, 2013. Polygonaceae: Buckwheat Family. Treatment from the Jepson Manual. http://ucjeps.berkeley.edu/cgi-bin/get_JM_treatment

Homeopathic Materia Medica, 2013. Polygonum punctatum. International Academy of Classical Homeopathy. http://www.vithoulkas.com/en/component/content/article/240-materia-medica-by-boericke/3741-polygonum-punctatum.html

Illinois Wildflowers, 2013. Water Smartweed: Persicaria punctate. Wetland Wildflowers. http://www.illinoiswildflowers.info/wetland/plants/water_smartweed.htm

Invasiveorg, 2013. Dotted smartweed: Persicaria punctata (Ell.) Small. Invasive and Exotic Species of North America. http://www.invasive.org/browse/subinfo.cfm?sub=14141

ITIS, 2013. Integrated Taxonomic Information System (ITIS). Washington, DC, USA: Smithsonian Institution/NMNH. http://www.itis.gov/

Justice OL, 1941. A study of dormancy in seeds of Polygonum. Agricultural Experiment Station. Memoir, No. 235. 43 pp.

Missouri Botanical Garden, 2014. Tropicos database. St. Louis, Missouri, USA: Missouri Botanical Garden. http://www.tropicos.org/

Moerman DE, 1998. Native American Ethnobotany. Oregon, USA: Timber Press, 927 pp.

New Zealand History online, 2012. US forces in New Zealand. http://www.nzhistory.net.nz/war/us-forces-in-new-zealand

PIER, 2013. Pacific Islands Ecosystems at Risk. Honolulu, Hawaii, USA: HEAR, University of Hawaii. http://www.hear.org/pier/index.html

Swearingen JM, 2013. Survey of invasive plants occurring on National Park Service lands, 2000-2007. http://www.invasive.org/species/list.cfm?id=103

Timson J, 1996. Polygonum hydropiper L. Journal of Ecology, 54:815-821.

USDA-ARS, 2013. Germplasm Resources Information Network (GRIN). Online Database. Beltsville, Maryland, USA: National Germplasm Resources Laboratory. https://npgsweb.ars-grin.gov/gringlobal/taxon/taxonomysearch.aspx

USDA-NRCS, 2013. The PLANTS Database. Baton Rouge, USA: National Plant Data Center. http://plants.usda.gov/

Wagner WI; Herbst DR; Sohmer SH, 1999. Manual of the Flowering Plants of Hawaii, revised edition. Honolulu, Hawaii, USA: University of Hawaii Press.

Webb CJ; Sykes WR; Garnock-Jones PJ, 1988. Flora of New Zealand Volume IV. Naturalised Pteridophytes, Gymnosperms and Dicotyledons. Christchurch, New Zealand: DSIR Botany Division, 1365 pp. http://floraseries.landcareresearch.co.nz/pages/Book.aspx?fileName=Flora%204.xml

Contributors

Top of page

Original text by:

Ian Popay, consultant, New Zealand, with the support of Landcare Research.

Distribution Maps

Top of page
You can pan and zoom the map
Save map