Persicaria is a genus of herbaceous flowering plants in the knotweed family, Polygonaceae. Plants of the genus are known commonly as knotweeds or smartweeds. It has a cosmopolitan distribution, with species occurring nearly worldwide. The genus was segregated from Polygonum.
Polygonum is a genus of about 130 species of flowering plants in the buckwheat and knotweed family Polygonaceae. Common names include knotweed and knotgrass. In the Middle English glossary of herbs Alphita, it was known as ars-smerte. There have been various opinions about how broadly the genus should be defined. For example, buckwheat has sometimes been included in the genus as Polygonum fagopyrum. Former genera such as Polygonella have been subsumed into Polygonum; other genera have been split off.
Persicaria maculosa is an annual plant in the buckwheat family, Polygonaceae. Common names include lady's thumb, spotted lady's thumb, Jesusplant, and redshank. It is widespread across Eurasia from Iceland south to Portugal and east to Japan. It is also present as an introduced and invasive species in North America, where it was first noted in the Great Lakes region in 1843 and has now spread through most of the continent.
Polygonum arenastrum, commonly known as equal-leaved knotgrass, is a summer annual flowering plant in the knotweed family Polygonaceae. Other common names include common knotweed, prostrate knotweed, mat grass, oval-leaf knotweed, stone grass, wiregrass, and door weed, as well as many others. It is native to Europe and can be found on other continents as an introduced species and a common noxious weed. Knotweed was first seen in North America in 1809 and is now seen across much of the United States and Canada.
Persicaria lapathifolia, known as pale persicaria, is a plant of the family Polygonaceae. It is considered to be native throughout most of the world, from arctic to tropical realms, except South America and Southern Africa. It is closely related to Persicaria maculosa and as such is considered a weed in Britain and Europe. Other common names for the plant include pale smartweed, curlytop knotweed, and willow weed. It is a species complex made up of a great many varying forms, sometimes considered varieties. The environment also has a strong influence on the morphology of an individual plant.
Persicaria hydropiper, also known as water pepper, marshpepper knotweed, arse smart or tade, is a plant of the family Polygonaceae. A widespread species, Persicaria hydropiper is found in Australia, New Zealand, temperate Asia, Europe and North America. The plant grows in damp places and shallow water. Cultivated varieties are eaten in East Asia for their pungent flavor.
Bistorta affinis, the Himalayan bistort, fleece flower, or knotweed, is a species of flowering plant in the family Polygonaceae, native to the Himalayas.
Reynoutria multiflora is a species of flowering plant in the buckwheat family Polygonaceae native to central and southern China. It is known by the English common names tuber fleeceflower and Chinese (climbing) knotweed. It is known as he shou wu in China and East Asia. Another name for the species is fo-ti, which is a misnomer.
Persicaria bicornis is a North American species of flowering plant in the buckwheat family (Polygonaceae). The common name is pink smartweed. It is native to the central and southwestern United States from northern Texas west to Arizona, east to Louisiana, and north as far as eastern Wyoming, South Dakota, Iowa, and Illinois.
Persicaria cespitosa, known as tufted knotweed, is a summer annual weedy plant of the family Polygonaceae, native to eastern Asia, from China to Japan and Southeast Asia, and introduced into North America. The plant grows to 3.5 feet (105 cm) in height with elliptic to lanceolate leaves, usually 20–75 mm long. It has small pink or red flowers arranged in tight terminal spikes.
Persicaria chinensis, commonly known as creeping smartweed or Chinese knotweed, is a plant species from the family Polygonaceae. It is widespread across China, Japan, the Indian Subcontinent, Indonesia, Malaysia, and Vietnam. It is a common plant in Malaysia and Vietnam, where it is used in herbal remedies, such as for the treatment of dysentery, enteritis, and sore throat. It is a weed in some coastal areas of New South Wales and Queensland in Australia.
Persicaria amphibia is a species of flowering plant in the knotweed family known by several common names, including longroot smartweed, water knotweed, water smartweed, and amphibious bistort. It is native to much of North America, Asia, Europe, and parts of Africa, and it grows elsewhere as an introduced species and sometimes a noxious weed.
Fallopia baldschuanica is an Asian species of flowering plant in the knotweed family known by several common names, including Russian-vine, Bukhara fleeceflower, Chinese fleecevine, mile-a-minute and silver lace vine. It is native to Asia, and is growing wild in parts of Europe and North and Central America as an introduced species.
Persicaria punctata is a species of flowering plant in the knotweed family known by the common names dotted smartweed and dotted knotweed.
Persicaria longiseta is a species of flowering plant in the knotweed family known by the common names Oriental lady's thumb, bristly lady's thumb, Asiatic smartweed, long-bristled smartweed, low smartweed, Asiatic waterpepper, bristled knotweed, bunchy knotweed, and tufted knotweed. It is native to Asia, and it is present in North America and Europe as an introduced species and often a weed.
Persicaria sagittata, common names American tearthumb, arrowleaf tearthumb, or arrowvine, is a plant species widespread in the eastern half of North America as well as in eastern Asia. It has been found in every state and province from Texas to Manitoba to Newfoundland to Florida, plus Colorado and Oregon. It also grows in China, the Russian Far East, Siberia, Korea, Japan, northern India and Mongolia. It grows in moist areas along lake shores, stream banks, etc.
Polygonum glaucum, common names seabeach knotweed and seaside knotweed, is a North American species of plant in the buckwheat family. It grows on the Atlantic Coast of the United States, from Alabama to Massachusetts, including in salt-water inlets such as Chesapeake Bay and the Hudson River.
Polygonum patulum, called tree hogweed, is a species of flowering plant in the knotweed family. It is native to the Mediterranean region, eastern Europe, the Caucasus, Siberia, Central Asia, Mongolia, and the Province of Xinjiang in northwestern China. It has also become sparingly naturalized in scattered locations in Australia and North America.
Persicaria decipiens, commonly known as slender knotweed, is a species of flowering plant native to Australia and Asia.
Koenigia × fennica, known as Finnish knotweed, is a hybrid between two species of Koenigia, K. alpina and K. weyrichii, members of the family Polygonaceae, the knotweed family. It generally only known as a cultivated garden plant, but plants have been recorded a few times surviving in abandoned areas in northern Europe, especially in Finland. The cultivar 'Johanniswolke' is considered an attractive ornamental perennial plant.
