A ruderal species is a plant species that is first to colonize disturbed lands. The disturbance may be natural – for example, wildfires or avalanches – or the consequences of human activities, such as construction ( of roads , of buildings , mining , etc.) or agriculture (abandoned fields, irrigation , etc.).
14-452: Knotweed is a common name for plants in several genera in the family Polygonaceae . Knotweed may refer to: Fallopia Persicaria Polygonum Reynoutria Reynoutria japonica or Japanese knotweed, a highly invasive species in Europe and North America [REDACTED] Index of plants with the same common name This page
28-414: A corolla and in some, the sepals are petal-like and colorful. The androecium is composed of three to eight stamens that are normally free or united at the base. The ovary consists of three united carpels that form a single locule , which produces only one ovule . The ovary is superior with basal or free-central placentation . The gynoecium terminates in 1 to 3 styles , each of which ends in
42-622: A competitive advantage over the native species that they, too, may permanently prevent a disturbed area from returning to its original state despite natural topsoil. Features contributing to a species' success as ruderal are: Ecologists have proposed various scales for quantifying ruderality, which can be defined as the "ability to thrive where there is disturbance through partial or total destruction of plant biomass" (Grime, Hodgson & Hunt, 1988). The ruderality scale of Grime presents values that are readily available, and it takes into account disturbance factors as well as other indicators such as
56-581: A few more genera have been erected, and some segregates of Brunnichia , Eriogonum , and Persicaria have been given generic status in major works. Some of the genera were found not to be monophyletic and their limits have been revised. These include Ruprechtia , Eriogonum , Chorizanthe , Persicaria , Aconogonon , Polygonum , Fallopia , and Muehlenbeckia . Most Polygonaceae are perennial herbaceous plants with swollen nodes , but trees , shrubs and vines are also present. The leaves of Polygonaceae are simple , and arranged alternately on
70-485: A food item. The leaves of the common sorrel ( Rumex acetosa ) are eaten in salads or as a leaf vegetable . Polygonaceae contain some of the most prolific weeds , including species of Persicaria, Rumex and Polygonum , as well as Japanese knotweed . Polygonaceae are very well-defined and have long been universally recognized. In the APG III system , the family is placed in the order Caryophyllales . Within
84-1066: A single stigma . As of March 2019 , Plants of the World Online accepted 56 genera: The following phylogenetic tree is based on two papers on the molecular phylogenetics of Polygonaceae. Symmeria Afrobrunnichia Brunnichia Antigonon Neomillspaughia Coccoloba Podopterus Leptogonum Ruprechtia Triplaris Gymnopodium Gilmania Pterostegia Eriogonum Chorizanthe Persicaria Bistorta Rubrivena Aconogonon Koenigia Fagopyrum (including Parapteropyrum ) Calligonum Pteropyrum Pteroxygonum Oxyria Rheum Rumex (including Emex ) Knorringia Atraphaxis Polygonella Polygonum Reynoutria Fallopia Muehlenbeckia Ruderal species The term ruderal originates from
98-495: Is an index of articles on plant species (or higher taxonomic groups) with the same common name ( vernacular name). If an internal link led you here, you may wish to edit the linking article so that it links directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Knotweed&oldid=1233368428 " Category : Set index articles on plant common names Hidden categories: Articles with short description Short description
112-467: Is different from Wikidata All set index articles 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 in his book, Genera Plantarum . The name may refer to
126-620: Is present worldwide, but is most diverse in the North Temperate Zone . Several species are cultivated as ornamentals . A few species of Triplaris provide lumber . The fruit of the sea grape ( Coccoloba uvifera ) is eaten, and in Florida , jelly is made from it and sold commercially. The seeds of two species of Fagopyrum , known as buckwheat , are eaten in the form of groats or used to make flour. The petioles of rhubarb ( Rheum rhabarbarum and hybrids) are
140-479: The circumscriptions of these two subfamilies have been changed in light of phylogenetic studies of DNA sequences . Genera related to Coccoloba and Triplaris were moved from Polygonoideae to Eriogonoideae. The genus Symmeria does not belong to either of these subfamilies because it is a sister to the rest of the family. Afrobrunnichia might constitute a new subfamily as well. Brandbyge wrote descriptions for 43 genera of Polygonaceae in 1993. Since then,
154-435: The stems . Each leaf has a peculiar pair of fused, sheathing stipules , known as an ochrea . Those species that do not have the nodal ochrea can be identified by their possession of involucrate flower heads . The flowers are normally bisexual , small, and actinomorphic , with a perianth of three to six sepals . After flowering , the sepals often become thickened and enlarged around the developing fruit . Flowers lack
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#1732781191201168-479: The Latin word rudus , meaning " rubble ". Ruderal species typically dominate the disturbed area for a few years, gradually losing the competition to other native species. However, in extreme disturbance circumstances, such as when the natural topsoil is covered with a foreign substance, a single-species ruderal community may become permanently established. In addition, some ruderal invasive species may have such
182-483: The many swollen nodes the stems of some species have, being derived from Greek [ poly meaning 'many' and gony meaning 'knee' or 'joint']. Alternatively, it may have a different origin, meaning 'many seeds'. The Polygonaceae comprise about 1200 species distributed into about 48 genera. The largest genera are Eriogonum (240 species), Rumex (200 species), Coccoloba (120 species), Persicaria (100 species) and Calligonum (80 species). The family
196-487: The order, it lies outside of the large clade known as the core Caryophyllales. It is a sister to the family Plumbaginaceae , which it does not resemble morphologically . The last comprehensive revision of the family was published in 1993 by John Brandbyge as part of The Families and Genera of Vascular Plants . Brandbyge followed earlier systems of plant classification in dividing Polygonaceae into two subfamilies , Eriogonoideae and Polygonoideae . Since 1993,
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