In horticulture , the term ( per- + -ennial , "through the year") is used to differentiate a plant from shorter-lived annuals and biennials . It has thus been defined as a plant that lives more than two years. The term is also loosely used to distinguish plants with little or no woody growth (secondary growth in girth) from trees and shrubs, which are also technically perennials . Notably, it is estimated that 94% of plant species fall under the category of perennials, underscoring the prevalence of plants with lifespans exceeding two years in the botanical world.
41-550: 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 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
82-443: A century plant can live for 80 years and grow 30 meters tall before flowering and dying. However, most perennials are polycarpic (or iteroparous ), flowering over many seasons in their lifetime. Perennials invest more resources than annuals into roots, crowns, and other structures that allow them to live from one year to the next. They often have a competitive advantage because they can commence their growth and leaf out earlier in
123-414: 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
164-940: A photolyase and the other, a protein involved in nucleotide excision repair ). Perennials that are cultivated include: woody plants like fruit trees grown for their edible fruits; shrubs and trees grown as landscaping ornamentals ; herbaceous food crops like asparagus , rhubarb , strawberries ; and subtropical plants not hardy in colder areas such as tomatoes , eggplant , and coleus (which are treated as annuals in colder areas). Perennials also include plants grown for their flowering and other ornamental value including bulbs (like tulips, narcissus, and gladiolus); lawn grass, and other groundcovers , (such as periwinkle and Dichondra ). Each type of plant must be separated differently; for example, plants with fibrous root systems like daylilies, Siberian iris, or grasses can be pried apart with two garden forks inserted back to back, or cut by knives. However, plants such as bearded irises have
205-555: 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 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
246-471: A hundred taxonomic publications. Such descriptions typically result from either the discovery of organisms with unique combinations of characters that do not fit existing families, or from phylogenetic analyses that reveal the need for reclassification. The taxonomic term familia was first used by French botanist Pierre Magnol in his Prodromus historiae generalis plantarum, in quo familiae plantarum per tabulas disponuntur (1689) where he called
287-666: A lack of widespread consensus within the scientific community for extended periods. The continual publication of new data and diverse opinions plays a crucial role in facilitating adjustments and ultimately reaching a consensus over time. The naming of families is codified by various international bodies using the following suffixes: Name changes at the family level are regulated by the codes of nomenclature. For botanical families, some traditional names like Palmae ( Arecaceae ), Cruciferae ( Brassicaceae ), and Leguminosae ( Fabaceae ) are conserved alongside their standardized -aceae forms due to their historical significance and widespread use in
328-407: A root system of rhizomes; these root systems should be planted with the top of the rhizome just above ground level, with leaves from the following year showing. The point of dividing perennials is to increase the amount of a single breed of plant in your garden. In the United States more than 900 million dollars worth of potted herbaceous perennial plants were sold in 2019. Although most of humanity
369-509: A significant practical role in biological education and research. They provide an efficient framework for teaching taxonomy, as they group organisms with general similarities while remaining specific enough to be useful for identification purposes. For example, in botany, learning the characteristics of major plant families helps students identify related species across different geographic regions, since families often have worldwide distribution patterns. In many groups of organisms, families serve as
410-1054: 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 Family (biology) Family ( Latin : familia , pl. : familiae )
451-479: A very few (e.g. Zostera ) occurring in shallow sea water. Herbaceous perennial plants are particularly dominant in conditions too fire-prone for trees and shrubs, e.g., most plants on prairies and steppes are perennials; they are also dominant on tundra too cold for tree growth. Nearly all forest plants are perennials, including trees and shrubs. Perennial plants are usually better long-term competitors, especially under stable, resource-poor conditions. This
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#1733094130591492-758: 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, 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
533-496: Is commonly referred to as the "walnut family". The delineation of what constitutes a family—or whether a described family should be acknowledged—is established and decided upon by active taxonomists . There are not strict regulations for outlining or acknowledging a family, yet in the realm of plants, these classifications often rely on both the vegetative and reproductive characteristics of plant species. Taxonomists frequently hold varying perspectives on these descriptions, leading to
574-783: Is due to the development of larger root systems which can access water and soil nutrients deeper in the soil and to earlier emergence in the spring. Annual plants have an advantage in disturbed environments because of their faster growth and reproduction rates. Each section contains a short list of species related to that topic, these are an example as the true lists would fill several books. Perennials grown for their decorative flowers include very many species and types. Some examples include: The majority of fruit bearing plants are perennial even in temperate climates. Examples include: Many herbs are perennial, including these examples: Many vegetable plants can grow as perennials in tropical climates, but die in cold weather. Examples of some of
615-483: Is fed by the re-sowing of the seeds of annual grain crops, (either naturally or by the manual efforts of humans), perennial crops provide numerous benefits. Perennial plants often have deep, extensive root systems which can hold soil to prevent erosion , capture dissolved nitrogen before it can contaminate ground and surface water, and out-compete weeds (reducing the need for herbicides ). These potential benefits of perennials have resulted in new attempts to increase
656-480: Is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy . It is classified between order and genus . A family may be divided into subfamilies , which are intermediate ranks between the ranks of family and genus. The official family names are Latin in origin; however, popular names are often used: for example, walnut trees and hickory trees belong to the family Juglandaceae , but that family
697-429: Is too cold or dry. In many parts of the world, seasonality is expressed as wet and dry periods rather than warm and cold periods, and deciduous perennials lose their leaves in the dry season. Some perennial plants are protected from wildfires because they have underground roots that produce adventitious shoots, bulbs, crowns , or stems ; other perennials like trees and shrubs may have thick cork layers that protect
738-569: The Prodromus of Augustin Pyramus de Candolle and the Genera Plantarum of George Bentham and Joseph Dalton Hooker this word ordo was used for what now is given the rank of family. Families serve as valuable units for evolutionary, paleontological, and genetic studies due to their relatively greater stability compared to lower taxonomic levels like genera and species. Families play
779-475: The astronomical symbol for the planet Jupiter . Perennial plants can be short-lived (only a few years) or long-lived. They include a wide assortment of plant groups from non-flowering plants like ferns and liverworts to highly diverse flowering plants like orchids , grasses , and woody plants . Plants that flower and fruit only once and then die are termed monocarpic or semelparous ; these species may live for many years before they flower. For example,
820-435: 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
861-447: The -idae suffix for animal family names, derived from the Greek 'eidos' meaning 'resemblance' or 'like'. The adoption of this naming convention helped establish families as an important taxonomic rank. By the mid-1800s, many of Linnaeus's broad genera were being elevated to family status to accommodate the rapidly growing number of newly discovered species. In nineteenth-century works such as
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#1733094130591902-446: The advantage of generating larger seedlings that can better compete with other plants. Perennials also produce seeds over many years. An important aspect of cold acclimation is overexpression of DNA repair genes. In Thinopyrum intermedium a perennial relative of common wheat Triticum aestivum , conditions of freezing stress were shown to be associated with large increases in expression of two DNA repair genes (one gene product
943-510: The dormancy period is over and new growth begins. In climates that are warm all year long, perennials may grow continuously. Annuals which complete their life cycle in one growing season, in contrast with perennials, produce seeds as the next generation and die; the seeds may survive cold or dry periods or germinate soon after dispersal depending on the climate. Some perennials retain their foliage year-round; these are evergreen perennials. Deciduous perennials shed all their leaves part of
984-566: 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, 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
1025-541: The growing season, and can grow taller than annuals. In doing so they can better compete for space and collect more light. Perennials typically grow structures that allow them to adapt to living from one year to the next through a form of vegetative reproduction rather than seeding. These structures include bulbs , tubers , woody crowns, rhizomes , turions , woody stems, or crowns which allows them to survive periods of dormancy over cold or dry seasons; these structures typically store carbohydrates which are used once
1066-620: The hormones produced due to environmental situations (i.e., seasons), reproduction, and stage of development to begin and halt the ability to grow or flower. There is also a distinction between the ability to grow and the actual task of growth. For example, most trees regain the ability to grow during winter but do not initiate physical growth until the spring and summer months. The start of dormancy can be seen in perennial plants through withering flowers, loss of leaves on trees, and halting of reproduction in both flowering and budding plants. Perennial species may produce relatively large seeds that have
1107-406: The literature. Family names are typically formed from the stem of a type genus within the family. In zoology, when a valid family name is based on a genus that is later found to be a junior synonym , the family name may be maintained for stability if it was established before 1960. In botany, some family names that were found to be junior synonyms have been conserved due to their widespread use in
1148-545: 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 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
1189-907: The primary level for taxonomic identification keys, making them particularly valuable for field guides and systematic work as they often represent readily recognizable groups of related organisms with shared characteristics. In ecological and biodiversity research, families frequently serve as the foundational level for identification in survey work and environmental studies. This is particularly useful because families often share life history traits or occupy similar ecological niches . Some families show strong correlations between their taxonomic grouping and ecological functions, though this relationship varies among different groups of organisms. The stability of family names has practical importance for applied biological work, though this stability faces ongoing challenges from new scientific findings. Modern molecular studies and phylogenetic analyses continue to refine
1230-486: The scientific literature. The family-group in zoological nomenclature includes several ranks: superfamily (-oidea), family (-idae), subfamily (-inae), and tribe (-ini). Under the principle of coordination, a name established at any of these ranks can be moved to another rank while retaining its original authorship and date, requiring only a change in suffix to reflect its new rank. New family descriptions are relatively rare in taxonomy, occurring in fewer than one in
1271-497: 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 a food item. The leaves of the common sorrel ( Rumex acetosa ) are eaten in salads or as a leaf vegetable . Polygonaceae contain some of
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1312-465: The seed yield of perennial species, which could result in the creation of new perennial grain crops. Some examples of new perennial crops being developed are perennial rice and intermediate wheatgrass . A perennial rice developed in 2018, was reported in 2023, to have provided a similar yield to replanted annual rice when evaluated over eight consecutive harvests. Perennial plants dominate many natural ecosystems on land and in fresh water, with only
1353-567: The seventy-six groups of plants he recognised in his tables families ( familiae ). The concept of rank at that time was not yet settled, and in the preface to the Prodromus Magnol spoke of uniting his families into larger genera , which is far from how the term is used today. In his work Philosophia Botanica published in 1751, Carl Linnaeus employed the term familia to categorize significant plant groups such as trees , herbs , ferns , palms , and so on. Notably, he restricted
1394-668: The spring and summer, die back every autumn and winter, and then return in the spring from their rootstock or other overwintering structure, are known as herbaceous perennials . However, depending on the rigours of the local climate (temperature, moisture, organic content in the soil, microorganisms), a plant that is a perennial in its native habitat, may be treated by a gardener as an annual and planted out every year, from seed, from cuttings, or from divisions. Tomato vines, for example, live several years in their natural tropical/ subtropical habitat but are grown as annuals in temperate regions because their above-ground biomass does not survive
1435-431: The stems. Herbaceous perennials from temperate and alpine regions of the world can tolerate the cold during winter. Perennial plants may remain dormant for long periods and then recommence growth and reproduction when the environment is more suitable, while most annual plants complete their life cycle during one growing period, and biennials have two growing periods. The meristem of perennial plants communicates with
1476-551: The understanding of family relationships, sometimes leading to reclassification. The impact of these changes varies among different groups of organisms – while some families remain well-defined and easily recognizable, others require revision as new evidence emerges about evolutionary relationships. This balance between maintaining nomenclatural stability and incorporating new scientific discoveries remains an active area of taxonomic practice. Perennial plant Perennials (especially small flowering plants ) that grow and bloom over
1517-556: The use of this term solely within the book's morphological section, where he delved into discussions regarding the vegetative and generative aspects of plants. Subsequently, in French botanical publications, from Michel Adanson 's Familles naturelles des plantes (1763) and until the end of the 19th century, the word famille was used as a French equivalent of the Latin ordo (or ordo naturalis ). The family concept in botany
1558-405: The winter. There is also a class of evergreen perennials which lack woody stems, such as Bergenia which retain a mantle of leaves throughout the year. An intermediate class of plants is known as subshrubs , which retain a vestigial woody structure in winter, e.g. Penstemon . The symbol for a perennial plant, based on Species Plantarum by Linnaeus , is [REDACTED] , which is also
1599-439: The year. Deciduous perennials include herbaceous and woody plants; herbaceous plants have stems that lack hard, fibrous growth, while woody plants have stems with buds that survive above ground during dormancy. Some perennials are semi-deciduous, meaning they lose some of their leaves in either winter or summer. Deciduous perennials shed their leaves when growing conditions are no longer suitable for photosynthesis, such as when it
1640-412: Was further developed by the French botanists Antoine Laurent de Jussieu and Michel Adanson . Jussieu's 1789 Genera Plantarum divided plants into 100 'natural orders,' many of which correspond to modern plant families. However, the term 'family' did not become standardized in botanical usage until after the mid-nineteenth century. In zoology , the family as a rank intermediate between order and genus
1681-435: Was introduced by Pierre André Latreille in his Précis des caractères génériques des insectes, disposés dans un ordre naturel (1796). He used families (some of them were not named) in some but not in all his orders of "insects" (which then included all arthropods ). The standardization of zoological family names began in the early nineteenth century. A significant development came in 1813 when William Kirby introduced