''Persicaria pensylvanica'' (syn. ''Polygonum pensylvanicum'') is a species of

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants th ...

in the

buckwheat Buckwheat (''Fagopyrum esculentum''), or common buckwheat, is a flowering plant in the knotweed family Polygonaceae cultivated for its grain-like seeds and as a cover crop. The name "buckwheat" is used for several other species, such as '' Fago ...

family,

Polygonaceae The Polygonaceae are a family of flowering plants known informally as the knotweed family or smartweed—buckwheat family in the United States. The name is based on the genus ''Polygonum'', and was first used by Antoine Laurent de Jussieu in 1789 ...

. It is native to parts of

North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...

, where it is widespread in Canada and the United States. It has also been noted as an

introduced species An introduced species, alien species, exotic species, adventive species, immigrant species, foreign species, non-indigenous species, or non-native species is a species living outside its native distributional range, but which has arrived there ...

in parts of Europe and South America.''Persicaria pensylvanica''.
Flora of North America. Common names include Pennsylvania smartweed and pinkweed.

Description

Pennsylvania smartweed is a variable annual herb reaching to tall. The upright, ribbed stems are branching or unbranched. The lance-shaped leaves reach up to about in length. The blade may be marked with a dark blotch. The brownish

ochrea An ochrea (Latin ''ocrea'', greave or protective legging), also spelled ocrea, is a plant structure formed of stipules fused into a sheath surrounding the stem, and is typically found in the Polygonaceae The Polygonaceae are a family of flower ...

at the base is up to . The

inflorescences An inflorescence is a group or cluster of flowers arranged on a Plant stem, stem that is composed of a main branch or a complicated arrangement of branches. Morphology (biology), Morphologically, it is the modified part of the shoot of sperma ...

grow at the top of the stem and from the leaf axils. The flowers have five pinkish or greenish

tepal A tepal is one of the outer parts of a flower (collectively the perianth). The term is used when these parts cannot easily be classified as either sepals or petals. This may be because the parts of the perianth are undifferentiated (i.e. of very ...

s each a few millimeters long. This plant grows in moist, disturbed habitat types, such as ponds,

reservoir A reservoir (; from French ''réservoir'' ) is an enlarged lake behind a dam. Such a dam may be either artificial, built to store fresh water or it may be a natural formation. Reservoirs can be created in a number of ways, including contro ...

s, riverbanks, irrigated fields, and ditches.

Ecology

This plant is an important part of the habitat for

waterfowl Anseriformes is an order of birds also known as waterfowl that comprises about 180 living species of birds in three families: Anhimidae (three species of screamers), Anseranatidae (the magpie goose), and Anatidae, the largest family, which in ...

and other birds, which use it for food and cover. At least 50 species of birds have been observed feeding on the seeds, including

duck Duck is the common name for numerous species of waterfowl in the family Anatidae. Ducks are generally smaller and shorter-necked than swans and geese, which are members of the same family. Divided among several subfamilies, they are a form t ...

geese A goose (plural, : geese) is a bird of any of several waterfowl species in the family (biology), family Anatidae. This group comprises the genera ''Anser (bird), Anser'' (the grey geese and white geese) and ''Branta'' (the black geese). Some o ...

rails Rail or rails may refer to: Rail transport *Rail transport and related matters *Rail (rail transport) or railway lines, the running surface of a railway Arts and media Film * ''Rails'' (film), a 1929 Italian film by Mario Camerini * ''Rail'' ( ...

, bobwhites,

mourning dove The mourning dove (''Zenaida macroura'') is a member of the dove family, Columbidae. The bird is also known as the American mourning dove, the rain dove, and colloquially as the turtle dove, and was once known as the Carolina pigeon and Caroli ...

, and

ring-necked pheasant The common pheasant (''Phasianus colchicus'') is a bird in the pheasant family (Phasianidae). The genus name comes from Latin ''phasianus'', "pheasant". The species name ''colchicus'' is Latin for "of Colchis" (modern day Georgia), a country on ...

. The seeds and other parts are eaten by mammals such as the

white-footed mouse The white-footed mouse (''Peromyscus leucopus'') is a rodent native to North America from Ontario, Quebec, Labrador, and the Maritime Provinces (excluding the island of Newfoundland) to the southwestern United States and Mexico. In the Maritimes, ...

muskrat The muskrat (''Ondatra zibethicus'') is a medium-sized semiaquatic rodent native to North America and an introduced species in parts of Europe, Asia, and South America. The muskrat is found in wetlands over a wide range of climates and habitat ...

raccoon The raccoon ( or , ''Procyon lotor''), sometimes called the common raccoon to distinguish it from other species, is a mammal native to North America. It is the largest of the procyonid family, having a body length of , and a body weight of ...

, and

fox squirrel The fox squirrel (''Sciurus niger''), also known as the eastern fox squirrel or Bryant's fox squirrel, is the largest species of tree squirrel native to North America. Despite the differences in size and coloration, it is sometimes mistaken for ...

.''Polygonum pensylvanicum'' L.
Plant Fact Sheet. USDA NRCS.

Traditional native American medicine

Native Americans have various uses for the plant. The Chippewa use it for

epilepsy Epilepsy is a group of non-communicable neurological disorders characterized by recurrent epileptic seizures. Epileptic seizures can vary from brief and nearly undetectable periods to long periods of vigorous shaking due to abnormal electrical ...

.''Polygonum pensylvanicum''
Native American Ethnobotany. University of Michigan, Dearborn. The

Iroquois The Iroquois ( or ), officially the Haudenosaunee ( meaning "people of the longhouse"), are an Iroquoian-speaking confederacy of First Nations peoples in northeast North America/ Turtle Island. They were known during the colonial years to ...

use it for

horse colic Colic in horses is defined as abdominal pain, but it is a clinical symptom rather than a diagnosis. The term colic can encompass all forms of gastrointestinal conditions which cause pain as well as other causes of abdominal pain not involving the g ...

. The

Menominee The Menominee (; mez, omǣqnomenēwak meaning ''"Menominee People"'', also spelled Menomini, derived from the Ojibwe language word for "Wild Rice People"; known as ''Mamaceqtaw'', "the people", in the Menominee language) are a federally recog ...

take a leaf infusion for hemorrhage of blood from the mouth and post-partum healing. The

Meskwaki The Meskwaki (sometimes spelled Mesquaki), also known by the European exonyms Fox Indians or the Fox, are a Native American people. They have been closely linked to the Sauk people of the same language family. In the Meskwaki language, the ...

use it on bleeding

hemorrhoid Hemorrhoids (or haemorrhoids), also known as piles, are vascular structures in the anal canal. In their normal state, they are cushions that help with stool control. They become a disease when swollen or inflamed; the unqualified term ''hemo ...

s.Smith, Huron H. 1928 Ethnobotany of the Meskwaki Indians. Bulletin of the Public Museum of the City of Milwaukee 4:175-326 (p. 236,237)

Notes

External links

''Polygonum pensylvanicum''.
United States Department of Agriculture plants profile
''Polygonum pensylvanicum''.
Freckmann Herbarium, University of Wisconsin, Stevens Point.
photo of herbarium specimen at Missouri Botanical Garden, collected in Missouri in 1893
{{Taxonbar, from=Q15596461 pensylvanica Flora of the Eastern United States Flora of Eastern Canada Plants used in traditional Native American medicine Garden plants of North America Plants described in 1753 Taxa named by Carl Linnaeus