Overview

Comprehensive Description

Comments

This is one of the more common smartweeds in wetland areas. It also occurs in flood-prone areas of woodlands. Water Smartweed is average-sized and not particularly showy, but the seeds are valuable to wildlife in wetlands. To identify a Smartweed species correctly, it is necessary to examine the racemes and ochreae (the leaf-sheaths that wrap around the stem). Water Smartweed produces erect racemes with sparsely distributed flowers, whereas some other Smartweed species produce racemes that droop (e.g., Persicaria lapthifolium), or that are densely packed with flowers (e.g., Persicaria pennsylvanica). The ochreae of Water Smartweed are hairless, except for a few long bristles at the top. Other smartweed species may have ochreae that are hairy across the surface, and they often have very short or no bristles at the top.
Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© John Hilty

Source: Illinois Wildflowers

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Description

This native plant is an annual or short-lived perennial that is 1-2½' tall, branching occasionally and rather erect in habit. The round stems are hairless and somewhat broader where the ocreae occur. The alternate leaves are up to 6" long and ¾" across. They are lanceolate-ovate or narrowly ovate, tapering to short petioles. These leaves are usually hairless, except for a few hairs along the lower midrib in some cases, and they have smooth margins. At the base of each leaf, is a sheath (ocrea) that wraps around the stem. This sheath is membraneous and hairless, except for a few long bristles along its upper edge. With age, it falls away from the stem. The upper stems terminate in more or less erect spike-like racemes about 2-6" in length. Each raceme has small flowers that are sparsely distributed along its length. Each flower is about 1/8" long, white or greenish white, and its outer surface (consisting of sepals) has glandular dots that are either pale- or dark-colored (if pale-colored, a hand lens may be necessary in order to see them). The 5 sepals of the flower are more or less tightly folded against each other, while the short style is divided at its base into 2 or 3 segments. The blooming period occurs from mid-summer to early fall, and lasts about 1-2 months. There is no noticeble floral scent. Each flower is replaced by an achene that is shiny, dark brown to black, three-angled, and rather oblong. This plant often forms colonies of varying size in wet areas.
Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© John Hilty

Source: Illinois Wildflowers

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Distribution

Range and Habitat in Illinois

Water Smartweed is a common plant that occurs in almost every county in Illinois (see Distribution Map). Habitats include moist openings in floodplain forests, swamps, seeps, borders of ponds and small streams, and drainage ditches. This plant is often found along the edge of water that is stagnant or slow-moving, and appears to favor degraded wetlands.
Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© John Hilty

Source: Illinois Wildflowers

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

National Distribution

Canada

Origin: Unknown/Undetermined

Regularity: Regularly occurring

Currently: Unknown/Undetermined

Confidence: Confident

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

National Distribution

Canada

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

National Distribution

Canada

Origin: Unknown/Undetermined

Regularity: Regularly occurring

Currently: Unknown/Undetermined

Confidence: Confident

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

B.C., Man., N.B., N.S., Ont., P.E.I., Que., Sask.; Ala., Ariz., Ark., Calif., Colo., Conn., Del., D.C., Fla., Ga., Idaho, Ill., Ind., Iowa, Kans., Ky., La., Maine, Md., Mass., Mich., Minn., Miss., Mo., Mont., Nebr., N.H., N.J., N.Mex., N.Y., N.C., N.Dak., Ohio, Okla., Oreg., Pa., R.I., S.C., S.Dak., Tenn., Tex., Vt., Va., Wash., W.Va., Wis., Wyo.; Mexico; West Indies (Puerto Rico); Central America (Guatemala); South America (Brazil); Pacific Islands (Hawaii).
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Missouri Botanical Garden, 4344 Shaw Boulevard, St. Louis, MO, 63110 USA

Source: Missouri Botanical Garden

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Distribution: North and South America, introduced elsewhere.
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Missouri Botanical Garden, 4344 Shaw Boulevard, St. Louis, MO, 63110 USA

Source: Missouri Botanical Garden

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Physical Description

Morphology

Description

Plants annual or perennial, 1.5-12 dm; roots also often arising from proximal nodes; rhizomes often present. Stems ascending to erect, branched, without noticeable ribs, glabrous, glandular-punctate. Leaves: ocrea brown, cylindric, (4-)9-18 mm, chartaceous, base inflated, margins truncate, ciliate with bristles 2-11 mm, surface glabrous or strigose, glandular-punctate; petiole 0.1-1 cm, glandular-punctate, leaves sometimes sessile; blade without dark triangular or lunate blotch adaxially, lanceolate to lanceolate-ovate or subrhombic, 4-10(-15) × 0.6-2.4 cm, base tapered or cuneate, margins antrorsely strigose, apex acute to acuminate, faces glabrous or scabrous along midveins, glandular-punctate. Inflorescences mostly terminal, sometimes also axillary, erect, interrupted, 50-200 × 4-8 mm; peduncle 30-60 mm, glabrous, glandular-punctate; 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-punctate 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 exserted, brownish black, usually 3-gonous, rarely biconvex, (1.8-)2.2-3.2 × 1.5-2.2 mm, shiny, smooth. 2n = 44.
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Missouri Botanical Garden, 4344 Shaw Boulevard, St. Louis, MO, 63110 USA

Source: Missouri Botanical Garden

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Description

Erect, 20-40 cm high, simple-branched, glabrous to pubescent or less hairy, annual herb. Stem simple or branched, glabrous to pubescent or ciliate. Leaves 1.5-7 x 0.4-1.75 cm, lanceolate to elliptic, acute - acuminate, pubescent, hairy or ciliate, margin entire, ciliate, glandular-punctate mostly on the ventral side. Ochreae 0.75-1.75 cm long, ciliate or fimbriate, ciliae or fimbriae ± equal to ochrea. Inflorescence few flowered terminal or axillary racemes. Ochreolae 1.0-2.0 mm long, ciliate or fimbriate, ciliae or fimbriae ± equal to ochreolae. Flowers, subsessile on erect ± decurved, axillary or terminal filiform 3-5 (-7) cm long racemes. Tepals 5, biseriate, unequal pink, obovate-elliptic, obtuse, acute 1.5-2 x 1-1.25 mm. Stamens 8, flaments ± equal. Ovary trigonous, elliptic; styles 3, free or free up to half with capitate stigmas. Nuts trigonous, 0.75-1 (-1.25) x c. 0.5 mm, brown, shining.
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Missouri Botanical Garden, 4344 Shaw Boulevard, St. Louis, MO, 63110 USA

Source: Missouri Botanical Garden

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Diagnostic Description

Synonym

Polygonum punctatum Elliott, Sketch Bot. S. Carolina 1: 455. 1817; P. acre Kunth var. leptostachyum Meisner; P. punctatum var. confertiflorum (Meisner) Small; P. punctatum var. ellipticum Fassett; P. punctatum var. leptostachyum (Meisner) Small; P. punctatum var. parviflorum Fassett; P. punctatum var. parvum Marie-Victorin & Rousseau
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Missouri Botanical Garden, 4344 Shaw Boulevard, St. Louis, MO, 63110 USA

Source: Missouri Botanical Garden

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Synonym

Polygonum punctatum Elliott in Bot. Soc. Carol. Georgia 1: 55. 1817; R.R.Stewart, Ann. Cat. Vasc. Pl. W. Pak. & Kashm. 211. 1972.
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Missouri Botanical Garden, 4344 Shaw Boulevard, St. Louis, MO, 63110 USA

Source: Missouri Botanical Garden

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Type Information

Isotype for Persicaria punctata var. tacubayana Nieuwl.
Catalog Number: US 797273
Collection: Smithsonian Institution, National Museum of Natural History, Department of Botany
Preparation: Pressed specimen
Collector(s): C. G. Pringle
Year Collected: 1897
Locality: Tacubaya., Distrito Federal, Mexico, North America
  • Isotype: Nieuwland, J. A. 1913. Amer. Midl. Naturalist. 3: 131.
Creative Commons Attribution 3.0 (CC BY 3.0)

© Smithsonian Institution, National Museum of Natural History, Department of Botany

Source: National Museum of Natural History Collections

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Holotype for Persicaria punctata var. tacubayana Nieuwl.
Catalog Number: US 316887
Collection: Smithsonian Institution, National Museum of Natural History, Department of Botany
Preparation: Pressed specimen
Collector(s): C. G. Pringle
Year Collected: 1897
Locality: Tacubaya., Distrito Federal, Mexico, North America
  • Holotype: Nieuwland, J. A. 1913. Amer. Midl. Naturalist. 3: 131.
Creative Commons Attribution 3.0 (CC BY 3.0)

© Smithsonian Institution, National Museum of Natural History, Department of Botany

Source: National Museum of Natural History Collections

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Isotype for Polygonum punctatum f. stipitatum Fassett
Catalog Number: US 2166154
Collection: Smithsonian Institution, National Museum of Natural History, Department of Botany
Preparation: Pressed specimen
Collector(s): N. C. Fassett
Locality: Colombia, South America
  • Isotype: Fassett, N. C. 1946. Caldasia. 4: 223.
Creative Commons Attribution 3.0 (CC BY 3.0)

© Smithsonian Institution, National Museum of Natural History, Department of Botany

Source: National Museum of Natural History Collections

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Isotype for Polygonum punctatum var. eciliatum Small
Catalog Number: US 797498
Collection: Smithsonian Institution, National Museum of Natural History, Department of Botany
Preparation: Pressed specimen
Collector(s): C. G. Pringle
Year Collected: 1892
Locality: Valley of Toluca., Mexico, North America
  • Isotype: Small, J. K. 1893. Bull. Torrey Bot. Club. 20: 214.
Creative Commons Attribution 3.0 (CC BY 3.0)

© Smithsonian Institution, National Museum of Natural History, Department of Botany

Source: National Museum of Natural History Collections

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Ecology

Habitat

Range and Habitat in Illinois

Water Smartweed is a common plant that occurs in almost every county in Illinois (see Distribution Map). Habitats include moist openings in floodplain forests, swamps, seeps, borders of ponds and small streams, and drainage ditches. This plant is often found along the edge of water that is stagnant or slow-moving, and appears to favor degraded wetlands.
Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© John Hilty

Source: Illinois Wildflowers

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Shallow water, shores, marshes, floodplain forests; 0-1500m.
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Missouri Botanical Garden, 4344 Shaw Boulevard, St. Louis, MO, 63110 USA

Source: Missouri Botanical Garden

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Reported from N.W.F. province from Akbarpur, B. L. Burtt 1045, 1052 (E), by R. R. Stewart, l.c. but we have not come across any specimen from our area. Seems to be a rare species. Also reported by Munshi & Javeid l.c. from Benhama (Ganderbal) and Srinagar, probably a recent introduction. Closely related to Persicaria pubescens in overall features but differs by having erect racemes and smaller nuts whereas in P. pubescens the racemes are drooping and nuts are larger.
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Missouri Botanical Garden, 4344 Shaw Boulevard, St. Louis, MO, 63110 USA

Source: Missouri Botanical Garden

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Associations

Faunal Associations

The nectar of the flowers attracts short-tongued Halictid bees, various kinds of wasps, Syrphid flies and other kinds of flies, and the occasional beetle, including ladybird beetles. The Halictid bees often collect pollen as well. The 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 Gastrophysa polygoni (Leaf Beetle sp.). See the Moth Table for a list of moth species that feed on smartweeds. The nutritious seeds of wetland smartweeds are popular with many species of ducks, seed-eating rails, and various songbirds (see Bird Table for a list of species), which may help to distribute the seeds. The plants and seeds of wetland smartweeds are a minor source of food to muskrats.
Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© John Hilty

Source: Illinois Wildflowers

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Flower-Visiting Insects of Dotted Smartweed in Illinois

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Life History and Behavior

Cyclicity

Flowering/Fruiting

Flowering Jun-Nov.
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Missouri Botanical Garden, 4344 Shaw Boulevard, St. Louis, MO, 63110 USA

Source: Missouri Botanical Garden

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Molecular Biology and Genetics

Molecular Biology

Statistics of barcoding coverage: Polygonum punctatum

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 1
Specimens with Barcodes: 8
Species With Barcodes: 1
Creative Commons Attribution 3.0 (CC BY 3.0)

© Barcode of Life Data Systems

Source: Barcode of Life Data Systems (BOLD)

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Conservation

Conservation Status

National NatureServe Conservation Status

Canada

Rounded National Status Rank: NNR - Unranked

United States

Rounded National Status Rank: N5 - Secure

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

NatureServe Conservation Status

Rounded Global Status Rank: T5 - Secure

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

National NatureServe Conservation Status

Canada

Rounded National Status Rank: N5 - Secure

United States

Rounded National Status Rank: N5 - Secure

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

NatureServe Conservation Status

Rounded Global Status Rank: T5 - Secure

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

National NatureServe Conservation Status

Canada

Rounded National Status Rank: NNR - Unranked

United States

Rounded National Status Rank: N5 - Secure

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

NatureServe Conservation Status

Rounded Global Status Rank: G5 - Secure

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Relevance to Humans and Ecosystems

Benefits

Cultivation

The preference is full or partial sun, moist to wet conditions, in mucky soil that is high in organic matter. This plant tolerates shallow standing water.
Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© John Hilty

Source: Illinois Wildflowers

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Wikipedia

Persicaria punctata

Persicaria punctata (syn. Polygonum punctatum) is a species of flowering plant in the knotweed family known by the common name dotted knotweed.

It is native to the Americas, where it can be found in moist and wet habitat types from Canada to Argentina. It is an extremely variable plant. It may be annual or perennial.

It grows from a rhizome and produces decumbent or erect stems which may just exceed one meter in length. The branching stems may root at nodes that come in contact with the substrate. The lance-shaped leaves are up to 15 centimeters long and have stipules widened into bristly brown ochrea that wrap around their bases. The inflorescence is a number of branching clusters of dotted greenish flowers with white edges, sometimes tinged pink.

Creative Commons Attribution Share Alike 3.0 (CC BY-SA 3.0)

Source: Wikipedia

Unreviewed

Article rating from 0 people

Default rating: 2.5 of 5

Notes

Comments

Persicaria punctata with 12 varieties in North America and South America. He also identified numerous specimens that he considered to be morphologically intermediate between various varieties. M. Dalci (1972) 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. Persicaria 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. Persicaria punctata is confused most frequently with P. hydropiper; the achenes are diagnostic.  

The Chippewa, Houma, and Iroquois prepared decoctions from leaves, flowers, and roots for use as analgesics as well as gastrointestinal, orthopedic, and psychological aids (D. E. Moerman 1998).

Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Missouri Botanical Garden, 4344 Shaw Boulevard, St. Louis, MO, 63110 USA

Source: Missouri Botanical Garden

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Disclaimer

EOL content is automatically assembled from many different content providers. As a result, from time to time you may find pages on EOL that are confusing.

To request an improvement, please leave a comment on the page. Thank you!