Poaceae
Overview
The Poaceae is a large and nearly ubiquitous family of flowering plants. Members of this family are commonly called grasses, although the term "grass" is also applied to plants that are not in the Poaceae lineage, including the rushes (Juncaceae
Juncaceae
Juncaceae, the rush family, are a monocotyledonous family of flowering plants. There are eight genera and about 400 species. Members of the Juncaceae are slow-growing, rhizomatous, herbaceous plants, and they may superficially resemble grasses. They often grow on infertile soils in a wide range...

) and sedges (Cyperaceae
Cyperaceae
Cyperaceae are a family of monocotyledonous graminoid flowering plants known as sedges, which superficially resemble grasses or rushes. The family is large, with some 5,500 species described in about 109 genera. These species are widely distributed, with the centers of diversity for the group...

). This broad and general use of the word "grass" has led to plants of the Poaceae often being called "true grasses". With over 10,025 currently accepted species, the Poaceae represent the fifth largest plant family.
Encyclopedia
The Poaceae is a large and nearly ubiquitous family of flowering plants. Members of this family are commonly called grasses, although the term "grass" is also applied to plants that are not in the Poaceae lineage, including the rushes (Juncaceae
Juncaceae
Juncaceae, the rush family, are a monocotyledonous family of flowering plants. There are eight genera and about 400 species. Members of the Juncaceae are slow-growing, rhizomatous, herbaceous plants, and they may superficially resemble grasses. They often grow on infertile soils in a wide range...

) and sedges (Cyperaceae
Cyperaceae
Cyperaceae are a family of monocotyledonous graminoid flowering plants known as sedges, which superficially resemble grasses or rushes. The family is large, with some 5,500 species described in about 109 genera. These species are widely distributed, with the centers of diversity for the group...

). This broad and general use of the word "grass" has led to plants of the Poaceae often being called "true grasses". With over 10,025 currently accepted species, the Poaceae represent the fifth largest plant family. Only the Orchidaceae
Orchidaceae
The Orchidaceae, commonly referred to as the orchid family, is a morphologically diverse and widespread family of monocots in the order Asparagales. Along with the Asteraceae, it is one of the two largest families of flowering plants, with between 21,950 and 26,049 currently accepted species,...

, Asteraceae
Asteraceae
The Asteraceae or Compositae , is an exceedingly large and widespread family of vascular plants. The group has more than 22,750 currently accepted species, spread across 1620 genera and 12 subfamilies...

, Fabaceae
Fabaceae
The Fabaceae or Leguminosae, commonly known as the legume, pea, or bean family, is a large and economically important family of flowering plants. The group is the third largest land plant family, behind only the Orchidaceae and Asteraceae, with 730 genera and over 19,400 species...

, and Rubiaceae
Rubiaceae
The Rubiaceae is a family of flowering plants, variously called the coffee family, madder family, or bedstraw family. The group contains many commonly known plants, including the economically important coffee , quinine , and gambier , and the horticulturally valuable madder , west indian jasmine ,...

 have more species.

Plant communities dominated by Poaceae are called grassland
Grassland
Grasslands are areas where the vegetation is dominated by grasses and other herbaceous plants . However, sedge and rush families can also be found. Grasslands occur naturally on all continents except Antarctica...

s; grasslands are estimated to comprise 20% of the vegetation cover of the Earth. Grass species also occur in many other habitats not formally considered to be grasslands, including different types of wetland
Wetland
A wetland is an area of land whose soil is saturated with water either permanently or seasonally. Wetlands are categorised by their characteristic vegetation, which is adapted to these unique soil conditions....

s (e.g., fens, marshes), forest
Forest
A forest, also referred to as a wood or the woods, is an area with a high density of trees. As with cities, depending where you are in the world, what is considered a forest may vary significantly in size and have various classification according to how and what of the forest is composed...

s and tundra
Tundra
In physical geography, tundra is a biome where the tree growth is hindered by low temperatures and short growing seasons. The term tundra comes through Russian тундра from the Kildin Sami word tūndâr "uplands," "treeless mountain tract." There are three types of tundra: Arctic tundra, alpine...

.

Poaceae are often considered to be the most important of all plant families to human economies: it includes the staple food
Food
Food is any substance consumed to provide nutritional support for the body. It is usually of plant or animal origin, and contains essential nutrients, such as carbohydrates, fats, proteins, vitamins, or minerals...

 grains and cereal
Cereal
Cereals are grasses cultivated for the edible components of their grain , composed of the endosperm, germ, and bran...

 crops grown around the world, lawn and forage grasses, and bamboo, which is widely used for construction throughout east Asia
East Asia
East Asia or Eastern Asia is a subregion of Asia that can be defined in either geographical or cultural terms...

 and sub-Saharan Africa
Sub-Saharan Africa
Sub-Saharan Africa as a geographical term refers to the area of the African continent which lies south of the Sahara. A political definition of Sub-Saharan Africa, instead, covers all African countries which are fully or partially located south of the Sahara...

. Civilization was founded largely on the ability to domesticate cereal grass crops around the world.

Description

Grasses generally have the following characteristics (the image gallery can be used for reference):

Poaceae have hollow stems
Plant stem
A stem is one of two main structural axes of a vascular plant. The stem is normally divided into nodes and internodes, the nodes hold buds which grow into one or more leaves, inflorescence , conifer cones, roots, other stems etc. The internodes distance one node from another...

 called culms, which are plugged (solid) at intervals called nodes, the points along the culm at which leaves arise. Grass leaves
Leaf
A leaf is an organ of a vascular plant, as defined in botanical terms, and in particular in plant morphology. Foliage is a mass noun that refers to leaves as a feature of plants....

 are alternate, distichous (in one plane) or rarely spiral, and parallel-veined. Each leaf is differentiated into a lower sheath, which hugs the stem for a distance and a blade with margins usually entire. The leaf blades of many grasses are hardened with silica phytolith
Phytolith
Some plants can take up silica in the soil, whereupon it is deposited within different intracellular and extracellular structures of the plant. After these plants decay, silica is redeposited in the soil in the form of phytoliths , which are rigid, microscopic structures of varying sizes and shapes...

s, which helps discourage grazing animals. In some grasses (such as sword grass
Sword grass
Sword grass is a name used for some species of grasses with blades that are sharp enough to cut human skin. This is because they contain many silica phytoliths, a hardening material in many plants. The sharp blades help to discourage herbivores from grazing, protecting the grasses around it as well....

), this makes the edges of the grass blades sharp enough to cut human skin. A membranous appendage or fringe of hairs, called the ligule
Ligule
A ligule — is a thin outgrowth at the junction of leaf and leafstalk of many grasses and sedges or a strap-shaped corolla, such as that of a ray floret in plants in the daisy family....

, lies at the junction between sheath and blade, preventing water or insects from penetrating into the sheath.

Flower
Flower
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs...

s of Poaceae are characteristically arranged in spikelets, each spikelet having one or more florets (the spikelets are further grouped into panicles or spikes
Raceme
A raceme is a type of inflorescence that is unbranched and indeterminate and bears pedicellate flowers — flowers having short floral stalks called pedicels — along the axis. In botany, axis means a shoot, in this case one bearing the flowers. In a raceme, the oldest flowers are borne...

). A spikelet consists of two (or sometimes fewer) bracts at the base, called glumes, followed by one or more florets. A floret consists of the flower surrounded by two bracts called the lemma
Lemma (botany)
Lemma is a phytomorphological term used in botany referring to a part of the spikelet of grasses . It is the lowermost of two chaff-like bracts enclosing the grass floret. It often bears a long bristle called an awn, and may be similar in form to the glumes - chaffy bracts at the base of each...

 (the external one) and the palea
Palea (botany)
Palea, in botany, refers to one of the bract-like organs of the grass spikelet . It is the uppermost of the two chaff-like bracts that enclose the grass floret . It is often cleft at the tip, implying that it may be a double structure derived from the union of two separate organs...

 (the internal). The flowers are usually hermaphroditic (maize
Maize
Maize known in many English-speaking countries as corn or mielie/mealie, is a grain domesticated by indigenous peoples in Mesoamerica in prehistoric times. The leafy stalk produces ears which contain seeds called kernels. Though technically a grain, maize kernels are used in cooking as a vegetable...

, monoecious, is an exception) and pollination
Pollination
Pollination is the process by which pollen is transferred in plants, thereby enabling fertilisation and sexual reproduction. Pollen grains transport the male gametes to where the female gamete are contained within the carpel; in gymnosperms the pollen is directly applied to the ovule itself...

 is always anemophilous
Anemophily
Anemophily or wind pollination is a form of pollination whereby pollen is distributed by wind. Anemophilous plants may be either gymnosperms or angiosperms ....

, that is, by wind. The perianth
Perianth
The term perianth has two similar but separate meanings in botany:* In flowering plants, the perianth are the outer, sterile whorls of a flower...

 is reduced to two scales, called lodicules, that expand and contract to spread the lemma and palea; these are generally interpreted to be modified sepals. This complex structure can be seen in the image on the left, portraying a wheat
Wheat
Wheat is a cereal grain, originally from the Levant region of the Near East, but now cultivated worldwide. In 2007 world production of wheat was 607 million tons, making it the third most-produced cereal after maize and rice...

 (Triticum aestivum) spike.

The fruit
Fruit
In broad terms, a fruit is a structure of a plant that contains its seeds.The term has different meanings dependent on context. In non-technical usage, such as food preparation, fruit normally means the fleshy seed-associated structures of certain plants that are sweet and edible in the raw state,...

 of Poaceae is a caryopsis
Caryopsis
In botany, a caryopsis is a type of simple dry fruit — one that is monocarpelate and indehiscent and resembles an achene, except that in a caryopsis the pericarp is fused with the thin seed coat....

, in which the seed coat is fused to the fruit wall and thus, not separable from it (as in a maize kernel).

Growth and development

Grass blades grow at the base of the blade and not from elongated stem tips. This low growth point evolved in response to grazing animals and allows grasses to be grazed
Grazing
Grazing generally describes a type of feeding, in which a herbivore feeds on plants , and also on other multicellular autotrophs...

 or mown regularly without severe damage to the plant.

Three general classifications of growth habit present in grasses: bunch-type (also called caespitose), stolon
Stolon
In biology, stolons are horizontal connections between organisms. They may be part of the organism, or of its skeleton; typically, animal stolons are external skeletons.-In botany:...

iferous, and rhizomatous
Rhizome
In botany and dendrology, a rhizome is a characteristically horizontal stem of a plant that is usually found underground, often sending out roots and shoots from its nodes...

.

The success of the grasses lies in part in their morphology and growth processes, and in part in their physiological diversity. Most of the grasses divide into two physiological groups, using the C3
C3 carbon fixation
carbon fixation is a metabolic pathway for carbon fixation in photosynthesis. This process converts carbon dioxide and ribulose bisphosphate into 3-phosphoglycerate through the following reaction:...

 and C4
C4 carbon fixation
C4 carbon fixation is one of three biochemical mechanisms, along with and CAM photosynthesis, used in carbon fixation. It is named for the 4-carbon molecule present in the first product of carbon fixation in these plants, in contrast to the 3-carbon molecule products in plants. fixation is an...

 photosynthetic pathways for carbon fixation. The C4 grasses have a photosynthetic pathway linked to specialized Kranz leaf anatomy that particularly adapts them to hot climates and an atmosphere low in carbon dioxide
Carbon dioxide
Carbon dioxide is a naturally occurring chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom...

.

C3 grasses are referred to as "cool season" grasses, while C4 plants are considered "warm season" grasses; they may be either annual
Annual plant
An annual plant is a plant that usually germinates, flowers, and dies in a year or season. True annuals will only live longer than a year if they are prevented from setting seed...

 or perennial.
  • Annual cool season - wheat
    Wheat
    Wheat is a cereal grain, originally from the Levant region of the Near East, but now cultivated worldwide. In 2007 world production of wheat was 607 million tons, making it the third most-produced cereal after maize and rice...

    , rye
    Rye
    Rye is a grass grown extensively as a grain and as a forage crop. It is a member of the wheat tribe and is closely related to barley and wheat. Rye grain is used for flour, rye bread, rye beer, some whiskeys, some vodkas, and animal fodder...

    , annual bluegrass (annual meadowgrass, Poa annua
    Poa annua
    Poa annua, or annual meadow grass , is a widespread low-growing turfgrass in temperate climates. Though P. annua is commonly considered a solely annual plant due to its name, perennial bio-types do exist. 'Poa' is Greek for fodder. It is one of the sweetest grasses for green fodder, but less ...

    ), and oat
    Oat
    The common oat is a species of cereal grain grown for its seed, which is known by the same name . While oats are suitable for human consumption as oatmeal and rolled oats, one of the most common uses is as livestock feed...

  • Perennial cool season - orchardgrass (cocksfoot, Dactylis glomerata
    Dactylis glomerata
    Dactylis glomerata, Cock's-foot and orchard grass, is a common species of grass in the genus Dactylis, native throughout most of Europe, temperate Asia, and northern Africa.-Distribution:...

    ), fescue (Festuca spp), Kentucky bluegrass and perennial ryegrass (Lolium perenne
    Lolium perenne
    Lolium perenne, common name Perennial Ryegrass, is a grass from the family Poaceae. It is native to Europe, Asia and northern Africa, but is widely cultivated and naturalised around the world.-Description:...

    )
  • Annual warm season - corn
    Maize
    Maize known in many English-speaking countries as corn or mielie/mealie, is a grain domesticated by indigenous peoples in Mesoamerica in prehistoric times. The leafy stalk produces ears which contain seeds called kernels. Though technically a grain, maize kernels are used in cooking as a vegetable...

    , sudangrass, and pearl millet
    Pearl millet
    Pearl millet is the most widely grown type of millet. Grown in Africa and the Indian subcontinent since prehistoric times, it is generally accepted that pearl millet originated in Africa and was subsequently introduced into India. The center of diversity, and suggested area of domestication, for...

  • Perennial warm season - big bluestem
    Big Bluestem
    Andropogon gerardii, known also as Big bluestem, Turkey foot, Prairie tallgrass, or simply Tallgrass, is a tall grass native to much of the Great Plains and Prairie regions of central North America- Description :...

    , indiangrass, bermudagrass and switchgrass
    Switchgrass
    Panicum virgatum, commonly known as switchgrass, is a perennial warm season bunchgrass native to North America, where it occurs naturally from 55°N latitude in Canada southwards into the United States and Mexico...

    .

Ecology

Biome
Biome
Biomes are climatically and geographically defined as similar climatic conditions on the Earth, such as communities of plants, animals, and soil organisms, and are often referred to as ecosystems. Some parts of the earth have more or less the same kind of abiotic and biotic factors spread over a...

s dominated by grasses are called grassland
Grassland
Grasslands are areas where the vegetation is dominated by grasses and other herbaceous plants . However, sedge and rush families can also be found. Grasslands occur naturally on all continents except Antarctica...

s. If only large contiguous areas of grasslands are counted, these biomes cover 31% of the planet's land. Grasslands go by various names depending on location, including pampas, plains, steppes, or prairie.

In addition to their use as forage worldwide by many grazing mammals, such as cattle and other livestock, deer, and elephants, grasses are used as food plants by many species of butterflies and moths
Moths
Moths may refer to:* Gustav Moths , German rower* The Moths!, an English indie rock band* MOTHS, members of the Memorable Order of Tin Hats...

; see List of Lepidoptera that feed on grasses.

The evolution of large grazing animals in the Cenozoic
Cenozoic
The Cenozoic era is the current and most recent of the three Phanerozoic geological eras and covers the period from 65.5 mya to the present. The era began in the wake of the Cretaceous–Tertiary extinction event at the end of the Cretaceous that saw the demise of the last non-avian dinosaurs and...

 has contributed to the spread of grasses. Without large grazers, a clearcut of fire-destroyed area would soon be colonized by grasses and, if there is enough rain, tree seedlings. The tree seedlings would eventually produce shade, which kills most grasses. Large animals, however, trample the seedlings, killing the trees. Grasses persist because their lack of woody stems helps them to resist the damage of trampling.

Evolution

Until recently, grasses were thought to have evolved around 55 million years ago, based on fossil records. However, recent findings of 65-million-year-old phytolith
Phytolith
Some plants can take up silica in the soil, whereupon it is deposited within different intracellular and extracellular structures of the plant. After these plants decay, silica is redeposited in the soil in the form of phytoliths , which are rigid, microscopic structures of varying sizes and shapes...

s resembling grass phytoliths (including ancestors of rice
Rice
Rice is the seed of the monocot plants Oryza sativa or Oryza glaberrima . As a cereal grain, it is the most important staple food for a large part of the world's human population, especially in East Asia, Southeast Asia, South Asia, the Middle East, and the West Indies...

 and bamboo
Bamboo
Bamboo is a group of perennial evergreens in the true grass family Poaceae, subfamily Bambusoideae, tribe Bambuseae. Giant bamboos are the largest members of the grass family....

) in Cretaceous
Cretaceous
The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...

 dinosaur
Dinosaur
Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...

 coprolite
Coprolite
A coprolite is fossilized animal dung. Coprolites are classified as trace fossils as opposed to body fossils, as they give evidence for the animal's behaviour rather than morphology. The name is derived from the Greek words κοπρος / kopros meaning 'dung' and λιθος / lithos meaning 'stone'. They...

s, may place the diversification of grasses to an earlier date. Indeed, revised dating of the origins of the rice tribe Oryzeae
Oryzeae
Oryzeae is a tribe of flowering plants in the grass family, Poaceae. It contains 12 genera, including both cultivated rice and wild rice .-Genera:* Chikusichloa Koidz.* Hygroryza Nees* Leersia Sw.* Luziola Juss....

 have been led to the suggestion that the date might be pushed back as early as 107 Ma to 129 Ma.

The relationships among the subfamilies Bambusoideae, Ehrhartoideae and Pooideae in the BEP clade have been resolved: Bambusoideae and Pooideae are more closely related than Ehrhartoideae. This separation occurred within a relatively short time span (~4 million years).

Distribution

The grass family is one of the most widely distributed and abundant groups of plants on Earth. They are found on every continent, and are essentially only absent from central Greenland and much of Antarctica.

Taxonomy

The most recent classification of the grass family recognizes 12 subfamilies:
  • Anomochlooideae, a small lineage of broad-leaved grasses that includes two genera (Anomochloa, Streptochaeta)
  • Pharoideae, a small lineage of grasses that includes three genera, including Pharus and Leptaspis
  • Puelioideae, a small lineage that includes the African genus Puelia
  • Pooideae
    Pooideae
    The Pooideae is a subfamily of the true grass family Poaceae. It includes some major cereals such as wheat, barley, oat, rye and many lawn and pasture grasses.- List :...

    , including wheat
    Wheat
    Wheat is a cereal grain, originally from the Levant region of the Near East, but now cultivated worldwide. In 2007 world production of wheat was 607 million tons, making it the third most-produced cereal after maize and rice...

    , barley
    Barley
    Barley is a major cereal grain, a member of the grass family. It serves as a major animal fodder, as a base malt for beer and certain distilled beverages, and as a component of various health foods...

    , oat
    Oat
    The common oat is a species of cereal grain grown for its seed, which is known by the same name . While oats are suitable for human consumption as oatmeal and rolled oats, one of the most common uses is as livestock feed...

    s, brome-grass (Bromus
    Bromus
    Bromus is a large genus of the grass family . Estimates in the scientific literature of the number of species have ranged from 100 to 400, but plant taxonomists currently recognize around 160–170 species...

    ), reed-grasses (Calamagrostis) and many lawn and pasture grasses
  • Bambusoideae
    Bambusoideae
    The Bambusoideae is a subfamily of the true grass family Poaceae, and is characterized by having 3 stigmas and are mostly tree-like. However, there are uncertainties at practically every taxonomic level within the Bambusoideae, and different types of data often result in support for differing...

    , including bamboo
    Bamboo
    Bamboo is a group of perennial evergreens in the true grass family Poaceae, subfamily Bambusoideae, tribe Bambuseae. Giant bamboos are the largest members of the grass family....

  • Ehrhartoideae, including rice
    Rice
    Rice is the seed of the monocot plants Oryza sativa or Oryza glaberrima . As a cereal grain, it is the most important staple food for a large part of the world's human population, especially in East Asia, Southeast Asia, South Asia, the Middle East, and the West Indies...

    , wild rice
    Wild rice
    Wild rice is four species of grasses forming the genus Zizania, and the grain which can be harvested from them. The grain was historically gathered and eaten in both North America and China...

  • Arundinoideae
    Arundinoideae
    The Arundinoideae is a subfamily of the true grass family Poaceae, including giant reed and common reed.-Genera:Tribe AmphipogoneaeAmphipogonDiplopogonTribe AristideaeAristidaSartidiaStipagrostiTribe ArundineaeArundo...

    , including giant reed, common reed
  • Centothecoideae
    Centothecoideae
    The Centothecoideae is a subfamily of the true grass family ....

    , a small subfamily of 11 genera that is sometimes included in Panicoideae
  • Chloridoideae
    Chloridoideae
    Chloridoideae is a subfamily of the true grass family . The systematics of the main group of genera is in need of revision; they are traditionally divided into several tribes like the Eragrostideae....

    , including the lovegrasses (Eragrostis, about 350 species, including teff
    Teff
    Eragrostis tef, known as teff, taf , or khak shir , is an annual grass, a species of lovegrass native to the northern Ethiopian Highlands of Northeast Africa....

    ), dropseeds (Sporobolus, some 160 species), finger millet
    Finger millet
    Eleusine coracana, commonly Finger millet , also known as African millet or Ragi is an annual plant widely grown as a cereal in the arid areas of Africa and Asia. E...

     (Eleusine coracana (L.) Gaertn.), and the muhly grasses (Muhlenbergia, about 175 species)
  • Panicoideae
    Panicoideae
    Panicoideae is a subfamily of the true grass family. It probably constitutes two well-distinct lineages, the Andropogonodae and the Panicodae, which are further subdivided into tribes and subtribes...

    , including panic grass, maize
    Maize
    Maize known in many English-speaking countries as corn or mielie/mealie, is a grain domesticated by indigenous peoples in Mesoamerica in prehistoric times. The leafy stalk produces ears which contain seeds called kernels. Though technically a grain, maize kernels are used in cooking as a vegetable...

    , sorghum
    Sorghum
    Sorghum is a genus of numerous species of grasses, one of which is raised for grain and many of which are used as fodder plants either cultivated or as part of pasture. The plants are cultivated in warmer climates worldwide. Species are native to tropical and subtropical regions of all continents...

    , sugarcane
    Sugarcane
    Sugarcane refers to any of six to 37 species of tall perennial grasses of the genus Saccharum . Native to the warm temperate to tropical regions of South Asia, they have stout, jointed, fibrous stalks that are rich in sugar, and measure two to six metres tall...

    , most millet
    Millet
    The millets are a group of small-seeded species of cereal crops or grains, widely grown around the world for food and fodder. They do not form a taxonomic group, but rather a functional or agronomic one. Their essential similarities are that they are small-seeded grasses grown in difficult...

    s, fonio
    Fonio
    Fonio is the term for cultivated grains in the Digitaria genus. These are notable in parts of West Africa and one species in India. The grains are very small.-White fonio :...

    , and bluestem grass
    Bluestem grass
    Bluestem can refer to various grasses:* Little bluestem * Big bluestem and other species of the genus Andropogon* Cane bluestem and Caucasian bluestem of the Bothriochloa genus...

    es
  • Micrairoideae
  • Danthonioideae, including pampas grass
    Pampas Grass
    Cortaderia selloana, commonly known as pampas grass, is a tall grass native to southern South America, including the pampas after which it is named, and Patagonia....



Depending on the classification followed, the family includes approximately 668 genera.

Etymology

The Poaceae was named by John Hendley Barnhart in 1895, based on the tribe Poeae (described in 1814 by Robert Brown), and the type genus Poa
Poa
Poa is a genus of about 500 species of grasses, native to the temperate regions of both hemispheres. Common names include meadow-grass , bluegrass , tussock , and speargrass. "Poa" is Greek for fodder...

(described in 1753 by Linnaeus). The term is derived from the Ancient Greek term for "grass".

Uses

Grasses are, in human terms, perhaps the most economically important plant family. Grasses' economic importance stems from several areas, including food production, industry, and lawns.

Food production

Agricultural grasses grown for their edible seeds are called cereal
Cereal
Cereals are grasses cultivated for the edible components of their grain , composed of the endosperm, germ, and bran...

s. Three cereals – rice
Rice
Rice is the seed of the monocot plants Oryza sativa or Oryza glaberrima . As a cereal grain, it is the most important staple food for a large part of the world's human population, especially in East Asia, Southeast Asia, South Asia, the Middle East, and the West Indies...

, wheat
Wheat
Wheat is a cereal grain, originally from the Levant region of the Near East, but now cultivated worldwide. In 2007 world production of wheat was 607 million tons, making it the third most-produced cereal after maize and rice...

, and maize
Maize
Maize known in many English-speaking countries as corn or mielie/mealie, is a grain domesticated by indigenous peoples in Mesoamerica in prehistoric times. The leafy stalk produces ears which contain seeds called kernels. Though technically a grain, maize kernels are used in cooking as a vegetable...

 (corn) – provide more than half of all calories eaten by humans. Of all crops, 70% are grasses. Cereals constitute the major source of carbohydrate
Carbohydrate
A carbohydrate is an organic compound with the empirical formula ; that is, consists only of carbon, hydrogen, and oxygen, with a hydrogen:oxygen atom ratio of 2:1 . However, there are exceptions to this. One common example would be deoxyribose, a component of DNA, which has the empirical...

s for humans and perhaps the major source of protein, and include rice
Rice
Rice is the seed of the monocot plants Oryza sativa or Oryza glaberrima . As a cereal grain, it is the most important staple food for a large part of the world's human population, especially in East Asia, Southeast Asia, South Asia, the Middle East, and the West Indies...

 in southern and eastern Asia, maize in Central
Central America
Central America is the central geographic region of the Americas. It is the southernmost, isthmian portion of the North American continent, which connects with South America on the southeast. When considered part of the unified continental model, it is considered a subcontinent...

 and South America
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...

, and wheat and barley
Barley
Barley is a major cereal grain, a member of the grass family. It serves as a major animal fodder, as a base malt for beer and certain distilled beverages, and as a component of various health foods...

 in Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...

, northern Asia and the Americas
Americas
The Americas, or America , are lands in the Western hemisphere, also known as the New World. In English, the plural form the Americas is often used to refer to the landmasses of North America and South America with their associated islands and regions, while the singular form America is primarily...

.

Sugarcane
Sugarcane
Sugarcane refers to any of six to 37 species of tall perennial grasses of the genus Saccharum . Native to the warm temperate to tropical regions of South Asia, they have stout, jointed, fibrous stalks that are rich in sugar, and measure two to six metres tall...

 is the major source of sugar
Sugar
Sugar is a class of edible crystalline carbohydrates, mainly sucrose, lactose, and fructose, characterized by a sweet flavor.Sucrose in its refined form primarily comes from sugar cane and sugar beet...

 production. Many other grasses are grown for forage and fodder
Fodder
Fodder or animal feed is any agricultural foodstuff used specifically to feed domesticated livestock such as cattle, goats, sheep, horses, chickens and pigs. Most animal feed is from plants but some is of animal origin...

 for animal
Animal
Animals are a major group of multicellular, eukaryotic organisms of the kingdom Animalia or Metazoa. Their body plan eventually becomes fixed as they develop, although some undergo a process of metamorphosis later on in their life. Most animals are motile, meaning they can move spontaneously and...

 feed, particularly for sheep and cattle
Cattle
Cattle are the most common type of large domesticated ungulates. They are a prominent modern member of the subfamily Bovinae, are the most widespread species of the genus Bos, and are most commonly classified collectively as Bos primigenius...

, thereby indirectly providing more human calories.

Industry

Grasses are used for construction. Scaffolding
Scaffolding
Scaffolding is a temporary structure used to support people and material in the construction or repair of buildings and other large structures. It is usually a modular system of metal pipes or tubes, although it can be from other materials...

 made from bamboo
Bamboo
Bamboo is a group of perennial evergreens in the true grass family Poaceae, subfamily Bambusoideae, tribe Bambuseae. Giant bamboos are the largest members of the grass family....

 is able to withstand typhoon-force winds that would break steel scaffolding. Larger bamboos and Arundo donax
Arundo donax
Arundo donax, Giant Cane, is a tall perennial cane growing in damp soils, either fresh or moderately saline. Other common names include Carrizo, Arundo, Spanish cane, Wild cane, and Giant reed....

have stout culms that can be used in a manner similar to timber, and grass roots stabilize the sod of sod house
Sod house
The sod house or "soddy" was a corollary to the log cabin during frontier settlement of Canada and the United States. The prairie lacked standard building materials such as wood or stone; however, sod from thickly-rooted prairie grass was abundant...

s. Arundo is used to make reeds for woodwind instrument
Woodwind instrument
A woodwind instrument is a musical instrument which produces sound when the player blows air against a sharp edge or through a reed, causing the air within its resonator to vibrate...

s, and bamboo is used for innumerable implements.

Grass fiber
Fiber
Fiber is a class of materials that are continuous filaments or are in discrete elongated pieces, similar to lengths of thread.They are very important in the biology of both plants and animals, for holding tissues together....

 can be used for making paper
Paper
Paper is a thin material mainly used for writing upon, printing upon, drawing or for packaging. It is produced by pressing together moist fibers, typically cellulose pulp derived from wood, rags or grasses, and drying them into flexible sheets....

, and for biofuel
Biofuel
Biofuel is a type of fuel whose energy is derived from biological carbon fixation. Biofuels include fuels derived from biomass conversion, as well as solid biomass, liquid fuels and various biogases...

 production.

Phragmites australis
Phragmites
Phragmites, the Common reed, is a large perennial grass found in wetlands throughout temperate and tropical regions of the world. Phragmites australis is sometimes regarded as the sole species of the genus Phragmites, though some botanists divide Phragmites australis into three or four species...

(common reed) is important in water treatment, wetland habitat preservation and land reclamation in Afro-Eurasia
Afro-Eurasia
Afro-Eurasia or less commonly Afrasia or Eurafrasia is the term used to describe the largest landmass on earth. It may be defined as a supercontinent, consisting of Africa and Eurasia...

.

Lawn and ornamental grasses

Grasses are the primary plant used in lawn
Lawn
A lawn is an area of aesthetic and recreational land planted with grasses or other durable plants, which usually are maintained at a low and consistent height. Low ornamental meadows in natural landscaping styles are a contemporary option of a lawn...

s, which themselves derive from grazed grassland
Grassland
Grasslands are areas where the vegetation is dominated by grasses and other herbaceous plants . However, sedge and rush families can also be found. Grasslands occur naturally on all continents except Antarctica...

s in Europe. They also provide an important means of erosion control (e.g., along roadsides), especially on sloping land.

Although supplanted by artificial turf
Artificial turf
Artificial turf is a surface manufactured from synthetic fibers made to look like natural grass. It is most often used in arenas for sports that were originally or are normally played on grass. However, it is now being used on residential lawns and commercial applications as well...

 in some games, grasses are still an important covering of playing surfaces in many sports, including football
Football (soccer)
Association football, more commonly known as football or soccer, is a sport played between two teams of eleven players with a spherical ball...

, tennis
Tennis
Tennis is a sport usually played between two players or between two teams of two players each . Each player uses a racket that is strung to strike a hollow rubber ball covered with felt over a net into the opponent's court. Tennis is an Olympic sport and is played at all levels of society at all...

, golf
Golf
Golf is a precision club and ball sport, in which competing players use many types of clubs to hit balls into a series of holes on a golf course using the fewest number of strokes....

, cricket
Cricket
Cricket is a bat-and-ball game played between two teams of 11 players on an oval-shaped field, at the centre of which is a rectangular 22-yard long pitch. One team bats, trying to score as many runs as possible while the other team bowls and fields, trying to dismiss the batsmen and thus limit the...

, and softball
Softball
Softball is a bat-and-ball sport played between two teams of 10 to 14 players. It is a direct descendant of baseball although there are some key differences: softballs are larger than baseballs, and the pitches are thrown underhand rather than overhand...

/baseball
Baseball
Baseball is a bat-and-ball sport played between two teams of nine players each. The aim is to score runs by hitting a thrown ball with a bat and touching a series of four bases arranged at the corners of a ninety-foot diamond...

.

Ornamental grass
Ornamental grass
Ornamental grasses are grasses grown as ornamental plants. They have become increasingly popular in gardens in recent years.-Classifications:...

es, such as perennial bunch grasses, are used in many styles of garden design
Garden design
Garden design is the art and process of designing and creating plans for layout and planting of gardens and landscapes. Garden design may be done by the garden owner themselves, or by professionals of varying levels of experience and expertise...

 for their foliage, inflorescences, seed heads, and slope stabilization. They are often used in natural landscaping
Natural landscaping
.Natural landscaping, also called native gardening, is the use of native plants, including trees, shrubs, groundcover, and grasses which are indigenous to the geographic area of the garden.-Maintenance:...

, xeriscaping
Xeriscaping
Xeriscaping and xerogardening refers to landscaping and gardening in ways that reduce or eliminate the need for supplemental water from irrigation...

, contemporary or modern landscaping, wildlife gardening, and native plant gardening.

Economically important grasses


Grain crops
GRAIN
GRAIN is a small international non-profit organisation that works to support small farmers and social movements in their struggles for community-controlled and biodiversity-based food systems. Our support takes the form of independent research and analysis, networking at local, regional and...

  • Barley
    Barley
    Barley is a major cereal grain, a member of the grass family. It serves as a major animal fodder, as a base malt for beer and certain distilled beverages, and as a component of various health foods...

  • Maize
    Maize
    Maize known in many English-speaking countries as corn or mielie/mealie, is a grain domesticated by indigenous peoples in Mesoamerica in prehistoric times. The leafy stalk produces ears which contain seeds called kernels. Though technically a grain, maize kernels are used in cooking as a vegetable...

     (Corn)
  • Oats
    OATS
    OATS - Open Source Assistive Technology Software - is a source code repository or "forge" for assistive technology software. It was launched in 2006 with the goal to provide a one-stop “shop” for end users, clinicians and open-source developers to promote and develop open source assistive...

  • Rice
    Rice
    Rice is the seed of the monocot plants Oryza sativa or Oryza glaberrima . As a cereal grain, it is the most important staple food for a large part of the world's human population, especially in East Asia, Southeast Asia, South Asia, the Middle East, and the West Indies...

  • Rye
    Rye
    Rye is a grass grown extensively as a grain and as a forage crop. It is a member of the wheat tribe and is closely related to barley and wheat. Rye grain is used for flour, rye bread, rye beer, some whiskeys, some vodkas, and animal fodder...

  • Sorghum
    Sorghum
    Sorghum is a genus of numerous species of grasses, one of which is raised for grain and many of which are used as fodder plants either cultivated or as part of pasture. The plants are cultivated in warmer climates worldwide. Species are native to tropical and subtropical regions of all continents...

  • Wheat
    Wheat
    Wheat is a cereal grain, originally from the Levant region of the Near East, but now cultivated worldwide. In 2007 world production of wheat was 607 million tons, making it the third most-produced cereal after maize and rice...

  • Millet
    Millet
    The millets are a group of small-seeded species of cereal crops or grains, widely grown around the world for food and fodder. They do not form a taxonomic group, but rather a functional or agronomic one. Their essential similarities are that they are small-seeded grasses grown in difficult...


Leaf and stem crops
  • Bamboo
    Bamboo
    Bamboo is a group of perennial evergreens in the true grass family Poaceae, subfamily Bambusoideae, tribe Bambuseae. Giant bamboos are the largest members of the grass family....

  • Marram grass
    Marram grass
    Ammophila is a genus consisting of two or three very similar species of grasses; common names for these grasses include Marram Grass, Bent Grass, and Beachgrass...

  • Meadow-grass
    Poa
    Poa is a genus of about 500 species of grasses, native to the temperate regions of both hemispheres. Common names include meadow-grass , bluegrass , tussock , and speargrass. "Poa" is Greek for fodder...

  • Reed
    Phragmites
    Phragmites, the Common reed, is a large perennial grass found in wetlands throughout temperate and tropical regions of the world. Phragmites australis is sometimes regarded as the sole species of the genus Phragmites, though some botanists divide Phragmites australis into three or four species...

  • Ryegrass
    Ryegrass
    Ryegrass is a genus of nine species of tufted grasses in the Pooideae subfamily of the Poaceae family. Also called tares , these plants are native to Europe, Asia and northern Africa, but are...

  • Sugarcane
    Sugarcane
    Sugarcane refers to any of six to 37 species of tall perennial grasses of the genus Saccharum . Native to the warm temperate to tropical regions of South Asia, they have stout, jointed, fibrous stalks that are rich in sugar, and measure two to six metres tall...


Lawn grasses
Lawn
A lawn is an area of aesthetic and recreational land planted with grasses or other durable plants, which usually are maintained at a low and consistent height. Low ornamental meadows in natural landscaping styles are a contemporary option of a lawn...

  • Bahia grass
    Bahia grass
    Paspalum notatum, also known as Bahia Grass, Common Bahia, or Pensacola Bahia, is a tropical to subtropical perennial grass...

  • Bent grass
    Agrostis
    Agrostis is a genus of over 100 species belonging to the grass family Poaceae, commonly referred to as the bent grasses...

  • Bermuda grass
    Cynodon
    Cynodon is a genus of nine species of grasses, native to warm temperate to tropical regions of the Old World. The genus as a whole as well as its species are commonly known as Bermuda Grass or Dog's Tooth Grass.-Species:...

  • Centipede grass
    Centipede grass
    Centipedegrass is a warm season lawn grass that is thick sod forming, uniform growing, and medium to light green colored. It has a coarse texture with short upright stems that grow to about 3-5 inches and spread by stolons....

  • Fescue
  • Meadow-grass
    Poa
    Poa is a genus of about 500 species of grasses, native to the temperate regions of both hemispheres. Common names include meadow-grass , bluegrass , tussock , and speargrass. "Poa" is Greek for fodder...

  • Ryegrass
    Ryegrass
    Ryegrass is a genus of nine species of tufted grasses in the Pooideae subfamily of the Poaceae family. Also called tares , these plants are native to Europe, Asia and northern Africa, but are...

  • St. Augustine grass
    St. Augustine grass
    St. Augustine Grass or Buffalo Grass is a warm season lawn grass that is popular for use in tropical and subtropical regions. It is a medium to high maintenance grass that forms a thick, carpetlike lawn, crowding out most weeds and other grasses.-Characteristics:St...

  • Zoysia
    Zoysia
    Zoysia is a genus of creeping grasses native to southeast and east Asia and Australasia. These species, commonly called zoysia or zoysiagrass, are found in coastal areas or grasslands. The genus is named after the Austrian botanist Karl von Zois.-Species:*Zoysia japonica Steud.*Zoysia macrantha...


Ornamental grass
Ornamental grass
Ornamental grasses are grasses grown as ornamental plants. They have become increasingly popular in gardens in recent years.-Classifications:...

es (Horticultural
Horticulture
Horticulture is the industry and science of plant cultivation including the process of preparing soil for the planting of seeds, tubers, or cuttings. Horticulturists work and conduct research in the disciplines of plant propagation and cultivation, crop production, plant breeding and genetic...

)
  • Calamagrostis
    Calamagrostis
    Calamagrostis, or Small-reed or Reedgrass, is a genus in the Grass family Poaceae with about 260 species that occur mainly in temperate regions of the Northern Hemisphere and the southern hemisphere. Towards equatorial latitudes, species of Calamagrostis generally occur at higher elevations in...

     spp.
  • Cortaderia
    Cortaderia
    Cortaderia is a genus of 20-25 species of grasses in the family Poaceae. Members of the genus are native to South America , New Zealand and New Guinea . The name of the genus is derived from the Argentine Spanish word cortadera, which in turn refers to the sharp serrations on the leaves....

     spp.
  • Deschampsia
    Deschampsia
    Deschampsia is a genus of grasses in the family Poaceae, commonly known as hair grass or tussock grass. There are 30 to 40 species....

     spp.
  • Festuca spp.
  • Melica
    Melica
    Melica is a genus of perennial grasses known generally as melic or melic grass. They are found in most temperate regions of the world. They are clumping grasses with long, erect stems bearing spikelets of papery grass flowers...

     spp.
  • Muhlenbergia
    Muhlenbergia
    Muhlenbergia is a genus of grass in the Poaceae family. It is named in honour of the American amateur botanist Gotthilf Heinrich Ernst Muhlenberg. There are around 155 species. Many are known by the common name muhly....

     spp.
  • Stipa
    Stipa
    This article is about a type of grass.For Speech Transmission Index for Public Address Systems, see Speech transmission index.For the Italian aircraft designer, see Luigi Stipa...

     spp.

Model organism
Model organism
A model organism is a non-human species that is extensively studied to understand particular biological phenomena, with the expectation that discoveries made in the organism model will provide insight into the workings of other organisms. Model organisms are in vivo models and are widely used to...

s
  • Brachypodium distachyon
    Brachypodium distachyon
    Brachypodium distachyon, commonly called purple false brome, is a grass species native to southern Europe, northern Africa and southwestern Asia east to India. It is related to the major cereal grain species wheat, barley, oats, maize, rice, rye, sorghum, and millet...

  • Maize (Corn)
  • Rice
  • Sorghum
  • Wheat

Grasses and society

Grasses have long had significance in human society. They have been cultivated as a food source for domesticated animals for up to 10,000 years, and have been used to make paper
Paper
Paper is a thin material mainly used for writing upon, printing upon, drawing or for packaging. It is produced by pressing together moist fibers, typically cellulose pulp derived from wood, rags or grasses, and drying them into flexible sheets....

 since the second century AD. Also, the primary ingredient of beer is usually barley or wheat, both of which have been used for this purpose for over 4,000 years.

Some common aphorism
Aphorism
An aphorism is an original thought, spoken or written in a laconic and memorable form.The term was first used in the Aphorisms of Hippocrates...

s involve grass. For example:
  • "The grass is always greener on the other side" suggests an alternate state of affairs will always seem preferable to one's own.
  • "Don't let the grass grow under your feet" tells someone to get moving.
  • "A snake
    Snake
    Snakes are elongate, legless, carnivorous reptiles of the suborder Serpentes that can be distinguished from legless lizards by their lack of eyelids and external ears. Like all squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales...

     in the grass" means dangers that are hidden.
  • "When elephants fight, it is the grass which suffers" tells of bystanders caught in the crossfire.


A folk myth about grass is that it refuses to grow where any violent death has occurred.

See also

  • Agrostology
    Agrostology
    Agrostology , sometimes graminology, is the scientific study of grasses. It typically encompasses the true grasses , as well as the more grasslike species of the sedge family , the rush family , and the bulrush or cattail family Typhaceae...

  • Grass
    Grass
    Grasses, or more technically graminoids, are monocotyledonous, usually herbaceous plants with narrow leaves growing from the base. They include the "true grasses", of the Poaceae family, as well as the sedges and the rushes . The true grasses include cereals, bamboo and the grasses of lawns ...

  • Bunch grass
  • Ornamental grass
    Ornamental grass
    Ornamental grasses are grasses grown as ornamental plants. They have become increasingly popular in gardens in recent years.-Classifications:...

  • Sedges
    Cyperaceae
    Cyperaceae are a family of monocotyledonous graminoid flowering plants known as sedges, which superficially resemble grasses or rushes. The family is large, with some 5,500 species described in about 109 genera. These species are widely distributed, with the centers of diversity for the group...

  • Rushes
    Juncaceae
    Juncaceae, the rush family, are a monocotyledonous family of flowering plants. There are eight genera and about 400 species. Members of the Juncaceae are slow-growing, rhizomatous, herbaceous plants, and they may superficially resemble grasses. They often grow on infertile soils in a wide range...


External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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