There are about 380,000 known species of plants, of which the majority, some 260,000, produce seeds. They range in size from single cells to the tallest trees. Green plants provide a substantial proportion of the world's molecular oxygen; the sugars they create supply the energy for most of Earth's ecosystems and other organisms, including animals, either consume plants directly or rely on organisms which do so. (Full article...)
Banksia coccinea, commonly known as the scarlet banksia, waratah banksia or Albany banksia, is an erect shrub or small tree in the familyProteaceae. Its distribution in the wild is along the south west coast of Western Australia, from Denmark to the Stokes National Park, and north to the Stirling Range, growing on white or grey sand in shrubland, heath or open woodland. Reaching up to 8 m (26 ft) in height, it is a single-stemmed plant that has oblong leaves, which are 3–9 cm (1.2–3.5 in) long and 2–7 cm (0.8–2.8 in) wide. The prominent red and white flower spikes appear mainly in the spring. As they age they develop small follicles that store seeds until opened by fire. Though widely occurring, it is highly sensitive to dieback and large populations of plants have succumbed to the disease.
Collected and described by Robert Brown in the early 19th century, Banksia coccinea appears to be most closely related to Banksia speciosa and B. baxteri. Banksia coccinea plants are killed by bushfire, and regenerate from seed. The flowers attract nectar- and insect-feeding birds, particularly honeyeaters, and a variety of insects. Widely considered one of the most attractive Banksia species, B. coccinea is a popular garden plant and one of the most important Banksia species for the cut flower industry; it is grown commercially in several countries including Australia, South Africa, Canada, the United States, New Zealand and Israel. In cultivation, B. coccinea grows well in a sunny location on well-drained soil, but it cannot survive in areas with humid or wet summers. (Full article...)
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Telopea speciosissima flowerhead with florets opening from the edges towards the centre, Blue Mountains, Australia
The floral emblem for its home state of New South Wales, Telopea speciosissima has featured prominently in art, architecture, and advertising, particularly since Australian federation. Commercially grown in several countries as a cut flower, it is also cultivated in home gardens, requiring good drainage yet adequate moisture, but is vulnerable to various fungal diseases and pests. A number of cultivars with various shades of red, pink and even white flowers are available. Horticulturists have also developed hybrids with T. oreades and T. mongaensis which are more tolerant of cold, shade, and heavier soils. (Full article...)
In nature, B. sceptrum grows in deep yellow or pale red sand in tall shrubland, commonly on dunes, being found as a shrub to 5 metres (16 ft) high, though often smaller in exposed areas. It is killed by fire and regenerates by seed, the woody follicles opening with fire. B. sceptrum is one of the most striking yellow-flowered banksias of all. Its tall bright yellow spikes, known as inflorescences, are terminal and well displayed. Flowering is in summer, mainly December and January, though flowers are occasionally seen at other times. (Full article...)
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Adiantum viridimontanum growing in a dunite roadcut
Adiantum viridimontanum, commonly known as Green Mountain maidenhair fern, is a fern found only in outcrops of serpentine rock in New England and Eastern Canada. The leaf blade is cut into finger-like segments, themselves once-divided, which are borne on the outer side of a curved, dark, glossy rachis. These finger-like segments are not individual leaves, but parts of a single compound leaf. The "fingers" may be drooping or erect, depending on whether the individual fern grows in shade or sunlight. Spores are borne under false indusia at the edge of the subdivisions of the leaf, a characteristic unique to the genus Adiantum.
Until 1991, A. viridimontanum was grouped with the western maidenhair fern, A. aleuticum, which grows both in western North America and as a disjunct on serpentine outcrops in eastern North America. At one time, A. aleuticum itself was classified as a variety (A. pedatum var. aleuticum) of the northern maidenhair fern, A. pedatum. However, after several years of study, botanist Cathy Paris recognized that A. aleuticum was a distinct species, and that some of the specimens that had been attributed to that taxon (group of organisms) were a third, hybrid species intermediate between A. pedatum and A. aleuticum. She named the new species A. viridimontanum for the site of its discovery in the Green Mountains in Vermont; it has since been located in Quebec and in one site in coastal Maine. (Full article...)
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Banksia aculeata, commonly known as prickly banksia, is a species of plant of the family Proteaceae native to the Stirling Range in the southwest of Western Australia. A shrub up to 2 m (7 ft) tall, it has dense foliage and leaves with very prickly serrated margins. Its unusual pinkish, pendent (hanging) flower spikes, known as inflorescences, are generally hidden in the foliage and appear during the early summer. Although it was collected by the naturalist James Drummond in the 1840s, Banksia aculeata was not formally described until 1981, by Alex George in his monograph of the genus.
A rare plant, Banksia aculeata is found in gravelly soils in elevated areas. Native to a habitat burnt by periodic bushfires, it is killed by fire and regenerates from seed afterwards. In contrast to other Western Australian banksias, it appears to have some resistance to the soil-borne water mouldPhytophthora cinnamomi. (Full article...)
Banksia spinulosa, the hairpin banksia, is a species of woody shrub, of the genus Banksia in the family Proteaceae, native to eastern Australia. Widely distributed, it is found as an understorey plant in open dry forest or heathland from Victoria to northern Queensland, generally on sandstone though sometimes also clay soils. It generally grows as a small shrub to 2 metres (7 ft) in height, though can be a straggly tree to 6 metres (20 ft). It has long narrow leaves with inflorescences which can vary considerably in coloration; while the spikes are gold or less commonly yellowish, the emergent styles may be a wide range of colours – from black, purple, red, orange or yellow.
Banksia spinulosa was named by James Edward Smith in England in 1793, after being collected by John White, most likely in 1792. He gave it the common name prickly-leaved banksia, though this has fallen out of use. With four currently recognised varieties, the species has had a complicated taxonomic history, with two varieties initially described as separate species in the early 19th century. A fourth, from the New England region, has only recently been described. However, there has been disagreement whether one, var. cunninghamii, is distinct enough to once again have specific status. The pre-eminent authority on Banksia, Alex George, concedes there is still more work to be done on the Banksia spinulosa complex. (Full article...)
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Banksia lemanniana, the yellow lantern banksia or Lemann's banksia, is a species of flowering plant in the familyProteaceae, native to Western Australia. It generally grows as an open woody shrub or small tree to 5 m (16 ft) high, with stiff serrated leaves and unusual hanging inflorescences. Flowering occurs over summer, the greenish buds developing into oval flower spikes before turning grey and developing the characteristic large woody follicles. It occurs within and just east of the Fitzgerald River National Park on the southern coast of the state. B. lemanniana is killed by bushfire and regenerates from seed.
Described by Swiss botanist Carl Meissner in 1856, Banksia lemanniana was named in honour of English botanist Charles Morgan Lemann. It is one of three or four related species all with pendent inflorescences, which is an unusual feature of banksias. No subspecies are recognised. Banksia lemanniana is classified as Not Threatened under the Wildlife Conservation Act of Western Australia. Unlike many Western Australian banksias, it appears to have some resistance to dieback from the soil-borne water mouldPhytophthora cinnamomi, and is one of the easier Western Australian species to grow in cultivation. (Full article...)
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Wild form of Xerochrysum bracteatum
Xerochrysum bracteatum, commonly known as the golden everlasting or strawflower, is a flowering plant in the family Asteraceae native to Australia. Described by Étienne Pierre Ventenat in 1803, it was known as Helichrysum bracteatum for many years before being transferred to a new genus Xerochrysum in 1990. It is an annual up to 1 m (3.3 ft) tall with green or grey leafy foliage. Golden yellow or white flower heads are produced from spring to autumn; their distinctive feature is the papery bracts that resemble petals. The species is widespread, growing in a variety of habitats across the country, from rainforest margins to deserts and subalpine areas. The golden everlasting serves as food for various larvae of lepidopterans (butterflies and moths), and adult butterflies, hoverflies, native bees, small beetles, and grasshoppers visit the flower heads.
The golden everlasting has proven very adaptable to cultivation. It was propagated and developed in Germany in the 1850s, and annual cultivars in a host of colour forms from white to bronze to purple flowers became available. Many of these are still sold in mixed seed packs. In Australia, many cultivars are perennial shrubs, which have become popular garden plants. Sturdier, long-stemmed forms are used commercially in the cut flower industry. (Full article...)
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Banksia prionotes, commonly known as acorn banksia or orange banksia, is a species of shrub or tree of the genus Banksia in the family Proteaceae. It is native to the southwest of Western Australia and can reach up to 10 m (33 ft) in height. It can be much smaller in more exposed areas or in the north of its range. This species has serrated, dull green leaves and large, bright flower spikes, initially white before opening to a bright orange. Its common name arises from the partly opened inflorescence, which is shaped like an acorn. The tree is a popular garden plant and also of importance to the cut flower industry.
Banksia prionotes was first described in 1840 by English botanist John Lindley, probably from material collected by James Drummond the previous year. There are no recognised varieties, although it has been known to hybridise with Banksia hookeriana. Widely distributed in south-west Western Australia, B. prionotes is found from Shark Bay (25° S) in the north, south as far as Kojonup (33°50′S). It grows exclusively in sandy soils, and is usually the dominant plant in scrubland or low woodland. Pollinated by birds, it provides food for a wide array of vertebrate and invertebrate animals in the autumn and winter months. It is an important source of food for honeyeaters (Meliphagidae), and is critical to their survival in the Avon Wheatbelt region, where it is the only nectar-producing plant in flower at some times of the year. (Full article...)
Banksia sessilis, commonly known as parrot bush, is a species of shrub or tree in the plantgenusBanksia of the family Proteaceae. It had been known as Dryandra sessilis until 2007, when the genus Dryandra was sunk into Banksia. The Noongar peoples know the plant as budjan or butyak. Widespread throughout southwestWestern Australia, it is found on sandy soils over laterite or limestone, often as an understorey plant in open forest, woodland or shrubland. Encountered as a shrub or small tree up to 6 m (20 ft) in height, it has prickly dark green leaves and dome-shaped cream-yellow flowerheads. Flowering from winter through to late spring, it provides a key source of food—both the nectar and the insects it attracts—for honeyeaters in the cooler months, and species diversity is reduced in areas where there is little or no parrot bush occurring. Several species of honeyeater, some species of native bee, and the European honey bee seek out and consume the nectar, while the long-billed black cockatoo and Australian ringneck eat the seed. The life cycle of Banksia sessilis is adapted to regular bushfires. Killed by fire and regenerating by seed afterwards, each shrub generally produces many flowerheads and a massive amount of seed. It can recolonise disturbed areas, and may grow in thickets.
Banksia sessilis has a somewhat complicated taxonomic history. It was collected from King George Sound in 1801 and described by Robert Brown in 1810 as Dryandra floribunda, a name by which it was known for many years. However, Joseph Knight had published the name Josephia sessilis in 1809, which had precedence due to its earlier date, and the specific name was formalised in 1924. Four varieties are recognised. It is a prickly plant with little apparent horticultural potential; none of the varieties are commonly seen in cultivation. A profuse producer of nectar, B. sessilis is valuable to the beekeeping industry. (Full article...)
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Persoonia lanceolata, commonly known as lance-leaf geebung, is a shrub native to New South Wales in eastern Australia. It reaches 3 m (10 ft) in height and has smooth grey bark and bright green foliage. Its small yellow flowers grow on racemes and appear in the austral summer and autumn (January to April), followed by green fleshy fruits (known as drupes) which ripen the following spring (September to October). Within the genus Persoonia, P. lanceolata belongs to the lanceolata group of 58 closely related species. It interbreeds with several other species found in its range.
The species is usually found in dry sclerophyll forest on sandstone-based nutrient-deficient soil. It has adapted to a fire-prone environment; plants lost in bushfires can regenerate through a ground-stored seed bank. Seedlings mostly germinate within two years of fires. Several species of native bee of the genus Leioproctus pollinate the flowers. Swamp wallabies are a main consumer of its fruit, and the seeds are spread in wallaby faeces. Its lifespan ranges from 25 to 60 years, though difficulties in propagation have seen low cultivation rates. (Full article...)
Banksia brownii, commonly known as feather-leaved banksia or Brown's banksia, is a species of shrub that grows in southwestWestern Australia. A plant with fine feathery leaves and large red-brown flower spikes, it usually grows as an upright bush around two metres (6.6 ft) high, but can also occur as a small tree or a low spreading shrub. First collected in 1829 and published the following year, it is placed in Banksiasubgenus Banksia, section Oncostylis, series Spicigerae. There are two genetically distinct forms.
Banksia brownii occurs naturally only in two population clusters between Albany and the Stirling Range in southwest Western Australia. In the Stirling Range it occurs among heath on rocky mountain slopes; further south it occurs among jarrahwoodland in shallow nutrient-poor sand. It has been evaluated as critically endangered by the International Union for Conservation of Nature (IUCN); all major populations are threatened by Phytophthora cinnamomi dieback, a disease to which the species is highly susceptible. Other threats include loss of habitat, commercial exploitation and changes to the fire regime. Highly valued by Australia's horticultural and cut flower industries, B. brownii is widely cultivated in areas not exposed to dieback. It prefers a sheltered position in soil with good drainage, and must be provided with some moisture over summer. (Full article...)
Banksia serrata, commonly known as the saw banksia, the old man banksia, the saw-tooth banksia or the red honeysuckle and as wiriyagan by the Cadigal people, is a species of woody shrub or tree of the genus Banksia, in the family Proteaceae. Native to the east coast of Australia, it is found from Queensland to Victoria with outlying populations on Tasmania and Flinders Island. Commonly growing as a gnarled tree up to 16 m (50 ft) in height, it can be much smaller in more exposed areas. This Banksia species has wrinkled grey bark, shiny dark green serrated leaves and large yellow or greyish-yellow flower spikes appearing over summer. The flower spikes, or inflorescences, turn grey as they age and pollinated flowers develop into large, grey, woody seed pods called follicles.
B. serrata is one of the four original Banksia species collected by Sir Joseph Banks in 1770, and one of four species published in 1782 as part of Carolus Linnaeus the Younger's original description of the genus. There are no recognised varieties, although it is closely related to Banksia aemula. Throughout its range, it grows exclusively in sandy soil, and is usually the dominant plant in scrubland or low woodland. B. serrata is pollinated by and provides food for a wide array of vertebrate and invertebrate animals in the autumn and winter months, and is an important source of food for honeyeaters. It is a common plant of parks and gardens. (Full article...)
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Telopea oreades, commonly known as the Gippsland-, mountain- or Victorian waratah, is a large shrub or small tree in the family Proteaceae. Native to southeastern Australia, it is found in wet sclerophyll forest and rainforest on rich acidic soils high in organic matter. No subspecies are recognised, though a northern isolated population hybridises extensively with the Braidwood waratah (T. mongaensis). Reaching a height of up to 19 metres (62 feet), T. oreades grows with a single trunk and erect habit. It has dark green leaves with prominent veins that are 11–28 centimetres (4.3–11 in) long and 1.5–6 cm (0.6–2.4 in) wide. The red flower heads, known as inflorescences, appear in late spring. Each is composed of up to 60 individual flowers.
In the garden, T. oreades grows in soils with good drainage and ample moisture in part-shaded or sunny positions. Several commercially available cultivars that are hybrid forms with T. speciosissima have been developed, such as the 'Shady Lady' series. The timber is hard and has been used for making furniture and tool handles. (Full article...)
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Flowers emerging from base of cone
Isopogon anethifolius, commonly known as narrow-leaf drumsticks or narrow-leafed drumsticks, is a shrub in the family Proteaceae. The species is found only in coastal areas near Sydney in New South Wales, and to the immediate west. It occurs naturally in woodland, open forest and heathland on sandstone soils. An upright shrub, it can reach to 3 m (9.8 ft) in height, with terete leaves that are divided and narrow. The yellow flowers appear in the Spring, from September to December, and are prominently displayed. They are followed by round grey cones, which give the plant its common name of drumsticks. The small hairy seeds are found in the old flower parts.
Isopogon anethifolius regenerates after bushfire by resprouting from its woody base, known as a lignotuber, as well as from seed. It was described by Richard Salisbury in 1796, and was first grown in the United Kingdom the same year. One of the easiest members of the genus Isopogon to grow in cultivation, I. anethifolius grows readily in the garden if located in a sunny or part-shaded spot with sandy soil and good drainage. (Full article...)
Genetically modified crops (GM crops) are plants used in agriculture, the DNA of which has been modified using genetic engineering methods. Plant genomes can be engineered by physical methods or by use of Agrobacterium for the delivery of sequences hosted in T-DNA binary vectors. In most cases, the aim is to introduce a new trait to the plant which does not occur naturally in the species. Examples in food crops include resistance to certain pests, diseases, environmental conditions, reduction of spoilage, resistance to chemical treatments (e.g. resistance to a herbicide), or improving the nutrient profile of the crop. Examples in non-food crops include production of pharmaceutical agents, biofuels, and other industrially useful goods, as well as for bioremediation.
Farmers have widely adopted GM technology. Acreage increased from 1.7 million hectares in 1996 to 185.1 million hectares in 2016, some 12% of global cropland. As of 2016, major crop (soybean, maize, canola and cotton) traits consist of herbicide tolerance (95.9 million hectares) insect resistance (25.2 million hectares), or both (58.5 million hectares). In 2015, 53.6 million ha of Genetically modified maize were under cultivation (almost 1/3 of the maize crop). GM maize outperformed its predecessors: yield was 5.6 to 24.5% higher with less mycotoxins (−28.8%), fumonisin (−30.6%) and thricotecens (−36.5%). Non-target organisms were unaffected, except for lower populations some parasitoid wasps due to decreased populations of their pest host European corn borer; European corn borer is a target of Lepidoptera active Bt maize. Biogeochemical parameters such as lignin content did not vary, while biomass decomposition was higher. (Full article...)
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Potato cultivars appear in a variety of colors, shapes, and sizes.
Wild potato species can be found from the southern United States to southern Chile. Genetic studies show that the potato has a single origin, in the area of present-day southern Peru and extreme northwestern Bolivia. Potatoes were domesticated there about 7,000–10,000 years ago from a species in the S. brevicaule complex. Many varieties of the potato are cultivated in the Andes region of South America, where the species is indigenous. (Full article...)
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Ethylene (CH 2=CH 2) is an unsaturatedhydrocarbon gas (alkene) acting as a naturally occurring plant hormone. It is the simplest alkene gas and is the first gas known to act as hormone. It acts at trace levels throughout the life of the plant by stimulating or regulating the ripening of fruit, the opening of flowers, the abscission (or shedding) of leaves and, in aquatic and semi-aquatic species, promoting the 'escape' from submergence by means of rapid elongation of stems or leaves. This escape response is particularly important in rice farming. Commercial fruit-ripening rooms use "catalytic generators" to make ethylene gas from a liquid supply of ethanol. Typically, a gassing level of 500 to 2,000 ppm is used, for 24 to 48 hours. Care must be taken to control carbon dioxide levels in ripening rooms when gassing, as high temperature ripening (20 °C; 68 °F) has been seen to produce CO2 levels of 10% in 24 hours. (Full article...)
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Structure of the photosynthetic reaction centre from Rhodopseudomonas viridis (PDB: 1PRC). Middle transmembrane section is the two subunits in this family; green blocks represent chlorophyll. Top section is the 4-heme (red) cytochrome c subunit (infobox below). The bottom section along with its connected TM helices is the H subunit.
Plants, algae, and cyanobacteria have one type of PRC for each of its two photosystems. Non-oxygenic bacteria, on the other hand, have an RC resembling either the Photosystem I centre (Type I) or the Photosystem II centre (Type II). In either case, PRCs have two related proteins (L/M; D1/D2; PsaA/PsaB) making up a quasi-symmetrical 5-helical core complex with pockets for pigment binding. The two types are structurally related and share a common ancestor. Each type have different pockets for ligands to accommodate their specific reactions: while Type I RCs use iron sulfur clusters to accept electrons, Type II RCs use quinones. The centre units of Type I RCs also have six extra transmembrane helices for gathering energy. (Full article...)
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Monocotyledons (/ˌmɒnəˌkɒtəˈliːdənz/), commonly referred to as monocots, (Lilianaesensu Chase & Reveal) are grass and grass-like flowering plants (angiosperms), the seeds of which typically contain only one embryonic leaf, or cotyledon. They constitute one of the major groups into which the flowering plants have traditionally been divided; the rest of the flowering plants have two cotyledons and are classified as dicotyledons, or dicots.
Monocotyledons have almost always been recognized as a group, but with various taxonomic ranks and under several different names. The APG III system of 2009 recognises a clade called "monocots" but does not assign it to a taxonomic rank. (Full article...)
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Pollen is a powdery substance produced by most types of flowers of seed plants for the purpose of sexual reproduction. It consists of pollen grains (highly reduced microgametophytes), which produce male gametes (sperm cells). Pollen grains have a hard coat made of sporopollenin that protects the gametophytes during the process of their movement from the stamens to the pistil of flowering plants, or from the male cone to the female cone of gymnosperms. If pollen lands on a compatible pistil or female cone, it germinates, producing a pollen tube that transfers the sperm to the ovule containing the female gametophyte. Individual pollen grains are small enough to require magnification to see detail. The study of pollen is called palynology and is highly useful in paleoecology, paleontology, archaeology, and forensics. Pollen in plants is used for transferring haploid male genetic material from the anther of a single flower to the stigma of another in cross-pollination. In a case of self-pollination, this process takes place from the anther of a flower to the stigma of the same flower.
Pollen is infrequently used as food and food supplement. Because of agricultural practices, it is often contaminated by agricultural pesticides. (Full article...)
Fruits are the means by which flowering plants (also known as angiosperms) disseminate their seeds. Edible fruits in particular have long propagated using the movements of humans and other animals in a symbiotic relationship that is the means for seed dispersal for the one group and nutrition for the other; humans and many other animals have become dependent on fruits as a source of food. Consequently, fruits account for a substantial fraction of the world's agricultural output, and some (such as the apple and the pomegranate) have acquired extensive cultural and symbolic meanings. (Full article...)
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Tropical vegetation is any vegetation in tropicallatitudes. Plant life that occurs in climates that are warm year-round is in general more biologically diverse that in other latitudes. Some tropical areas may receive abundant rain the whole year round, but others have long dry seasons which last several months and may vary in length and intensity with geographic location. These seasonal droughts have great impact on the vegetation, such as in the Madagascar spiny forests.
Rainforest vegetation is categorized by five layers. The top layer being the upper tree layer. Here you will find the largest and widest trees in all the forest. These trees tend to have very large canopy's so they can be fully exposed to sunlight. A layer below that is the middle tree layer. Here you will find more compact trees and vegetation. These trees tend to be more skinny as they are trying to gain any sunlight they can. The third layer is the lower tree area. These trees tend to be around five to ten meters high and tightly compacted. The trees found in the third layer are young trees trying to grow into the larger canopy trees. The fourth layer is the shrub layer beneath the tree canopy. This layer is mainly populated by sapling trees, shrubs, and seedlings. The fifth and final layer is the herb layer which is the forest floor. The forest floor is mainly bare except for various plants, mosses, and ferns. The forest floor is much more dense than above because of little sunlight and air movement. (Full article...)
The arrival of humans around 50,000 years ago and the settlement by Europeans from 1788, has had a significant impact on the flora. The use of fire-stick farming by Aboriginal people led to significant changes in the distribution of plant species over time, and the large-scale modification or destruction of vegetation for agriculture and urban development since 1788 has altered the composition of most terrestrial ecosystems, leading to the extinction of 61 plant species by 2006, and endangering over 1000 more. (Full article...)
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An arboretum (pl.: arboreta) is a botanical collection composed exclusively of trees of a variety of species. Originally mostly created as a section in a larger garden or park for specimens of mostly non-local species, many modern arboreta are in botanical gardens as living collections of woody plants and are intended at least in part for scientific study.
In Latin, an arboretum is a place planted with trees, not necessarily in this specific sense, and "arboretum" as an English word is first recorded used by John Claudius Loudon in 1833 in The Gardener's Magazine, but the concept was already long-established by then. (Full article...)
Agroforestry can be practiced for economic, environmental, and social benefits, and can be part of sustainable agriculture. Apart from production, benefits from agroforestry include improved farm productivity, healthier environments, reduction of risk for farmers, beauty and aesthetics, increased farm profits, reduced soil erosion, creating wildlife habitat, less pollution, managing animal waste, increased biodiversity, improved soil structure, and carbon sequestration. (Full article...)
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Jean H. Langenheim (née Harmon; September 5, 1925 – March 28, 2021) was an American plant ecologist and ethnobotanist, highly respected as an eminent scholar and a pioneer for women in the field. She has done field research in arctic, tropical, and alpine environments across five continents, with interdisciplinary research that spans across the fields of chemistry, geology, and botany. Her early research helped determine the plant origins of amber and led to her career-long work investigating the chemical ecology of resin-producing trees, including the role of plant resins for plant defense and the evolution of several resin-producing trees in the tropics. She wrote what is regarded as the authoritative reference on the topic: Plant Resins: Chemistry, Evolution, Ecology, and Ethnobotany, published in 2003.
Langenheim earned a PhD in botany with a minor in geology in 1953 from the University of Minnesota. She was the first female faculty member in the natural sciences and first woman to be promoted to full professor at the University of California, Santa Cruz. She was the first woman to serve as president for the Association for Tropical Biology, second woman to serve as president of the Ecological Society of America (ESA) and Society for Economic Botany, founded and served as the first president for the International Society of Chemical Ecology, and was a fellow of the American Association for the Advancement of Science and the California Academy of Sciences. During her time as ESA president, she initiated a project to document women's experiences and contributions to the field of ecology and conducted a follow-up project in 1996. Her research was summarized in two publications, and resulted in a large historical collection and a continued effort by ESA to document women's contributions to the field. (Full article...)
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This is a list of crop plants pollinated by bees along with how much crop yield is improved by bee pollination. Most of them are pollinated in whole or part by honey bees and by the crop's natural pollinators such as bumblebees, orchard bees, squash bees, and solitary bees. Where the same plants have non-bee pollinators such as birds or other insects like flies, these are also indicated.
Pollination by insects is called entomophily. Entomophily is a form of plant pollination whereby pollen is distributed by insects, particularly bees, Lepidoptera (butterflies and moths), flies and beetles. Honey bees pollinate many plant species that are not native to their natural habitat but are often inefficient pollinators of such plants; if they are visiting ten different species of flower, only a tenth of the pollen they carry may be the right species. Other bees tend to favor one species at a time, therefore do most of the actual pollination. (Full article...)
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Entomophily or insect pollination is a form of pollination whereby pollen of plants, especially but not only of flowering plants, is distributed by insects. Flowers pollinated by insects typically advertise themselves with bright colours, sometimes with conspicuous patterns (honey guides) leading to rewards of pollen and nectar; they may also have an attractive scent which in some cases mimics insect pheromones. Insect pollinators such as bees have adaptations for their role, such as lapping or sucking mouthparts to take in nectar, and in some species also pollen baskets on their hind legs. This required the coevolution of insects and flowering plants in the development of pollination behaviour by the insects and pollination mechanisms by the flowers, benefiting both groups. Both the size and the density of a population are known to affect pollination and subsequent reproductive performance. (Full article...)
German chamomile (Matricaria recutita) is an annual plant of the sunflower family Asteraceae. The flowers are borne in paniculatecapitula called calathids. The white ray florets have a single fused five-parted ligule, while the disc florets are yellow. In Northern temperate regions the flowers bloom in June and July and have a strong, aromatic smell.
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The parsnip (Pastinaca sativa) is a root vegetable closely related to carrot and parsley, all belonging to the flowering plant family Apiaceae. It is a biennial plant usually grown as an annual. Its long taproot has cream-colored skin and flesh, and, left in the ground to mature, becomes sweeter in flavor after winter frosts. In its first growing season, the plant has a rosette of pinnate, mid-green leaves. If unharvested, it produces a flowering stem topped by an umbel of small yellow flowers in its second growing season, later producing pale brown, flat, winged seeds. By this time, the stem has become woody, and the tap root inedible. Precautions should be taken when handling the stems and foliage, as parsnip sap can cause a skin rash or even blindness if exposed to sunlight after handling.
The parsnip is native to Eurasia; it has been used as a vegetable since antiquity and was cultivated by the Romans, although some confusion exists between parsnips and carrots in the literature of the time. It was used as a sweetener before the arrival of cane sugar in Europe. (Full article...)
Betula pubescens (syn. Betula alba), commonly known as downy birch and also as moor birch, white birch, European white birch or hairy birch, is a species of deciduous tree, native and abundant throughout northern Europe and northern Asia, growing farther north than any other broadleaf tree. It is closely related to, and often confused with, the silver birch (B. pendula), but grows in wetter places with heavier soils and poorer drainage; smaller trees can also be confused with the dwarf birch (B. nana).
Six varieties are recognised and it hybridises with the silver and dwarf birches. A number of cultivars have been developed but many are no longer in cultivation. The larva of the autumnal moth (Epirrita autumnata) feeds on the foliage and in some years, large areas of birch forest can be defoliated by this insect. Many fungi are associated with the tree and certain pathogenic fungi are the causal agents of birch dieback disease. (Full article...)
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Habit
Hypericum androsaemum, the shrubby St. John's wort, is a flowering plant in the family Hypericaceae. Commonly called tutsan or sweet-amber, the species is cultivated as an ornamental plant because of its striking red-tinted foliage, bright yellow petals, and its large clusters of fruit. Cultivars like 'Albury Purple' and 'Golden Tutsan' which have leaves with more pronounced purple and golden coloring, respectively.
The plant is native to Western Europe, North Africa and the Middle East, but has been introduced elsewhere in temperate areas with high rainfall, including Australia and New Zealand. In these countries, it is often considered a noxious weed. The plant is easily dispersed across wide ranges because of its small and numerous seeds, and methods for biological control are required to manage the species. (Full article...)
Durio graveolens, sometimes called the red-fleshed durian, orange-fleshed durian, or yellow durian, is a species of tree in the family Malvaceae. It is one of six species of durian named by Italian naturalist Odoardo Beccari. The specific epithetgraveolens ('strong smelling' or 'rank') is due to the odor. Although most species of Durio (most notably Durio dulcis) have a strong scent, the red-fleshed type of D. graveolens has a mild scent. It is native to Southeast Asia.
D. graveolens is an edible durian, perhaps the most popular 'wild' species of durian, and it is sold commercially regionally. However, its congenerDurio zibethinus is the typical species eaten and dominates sales worldwide. (Full article...)
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The bush coconut, or bloodwood apple, is an Australian bush tucker food. It is an insect gall with both plant and animal components: an adult female scale insect and her offspring (of genus Cystococcus) live in a gall induced on a bloodwood eucalypt tree (Corymbia). Bush coconuts can vary from golf ball to tennis ball size. They have a hard and lumpy outer layer. The inner layer is a white flesh that contains the female insect and her offspring. There are three known species of Cystococcus responsible for forming the bush coconut: Cystococcus pomiformis, Cystococcus echiniformis and Cystococcus campanidorsalis. C. pomiformis is the most common species. The bush coconut is found in Western Australia, the Northern Territory, Queensland and New South Wales.
The bush coconut is picked from the host tree and cracked open to allow the flesh and scale insects to be eaten. Both have a high protein content and are used as a food source by humans and other animals. The name 'bush coconut' is derived from the white flesh of the inner layer, which is similar in appearance to that of a coconut, and the taste of the flesh has been said to have a coconut flavour. The bush coconut has been depicted in Indigenous Australian dreaming and used as inspiration in their artwork. (Full article...)
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A portrait of Christian Ramsay, beside a watercolour of a flower and a bird
The orange originated in a region encompassing Southern China, Northeast India, and Myanmar; the earliest mention of the sweet orange was in Chinese literature in 314 BC. Orange trees are widely grown for their sweet fruit. The fruit of the orange tree can be eaten fresh, or processed for its juice or fragrant peel. In 2022, 76 million tonnes of oranges were grown worldwide, with Brazil producing 22% of the total, followed by India and China. (Full article...)
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A mature Asplenium bradleyi growing in a crevice in schist
Asplenium bradleyi, commonly known as Bradley's spleenwort or cliff spleenwort, is a rare epipetricfern of east-central North America. Named after Professor Frank Howe Bradley, who first collected it in Tennessee, it may be found infrequently throughout much of the Appalachian Mountains, the Ozarks, and the Ouachita Mountains, growing in small crevices on exposed sandstone cliffs. The species originated as a hybrid between mountain spleenwort (Asplenium montanum) and ebony spleenwort (Asplenium platyneuron); A. bradleyi originated when that sterile diploid hybrid underwent chromosome doubling to become a fertile tetraploid, a phenomenon known as allopolyploidy. Studies indicate that the present population of Bradley's spleenwort arose from several independent doublings of sterile diploid hybrids. A. bradleyi can also form sterile hybrids with several other spleenworts.
While A. bradleyi is easily outcompeted by other plants in more fertile habitats, it is well adapted to the thin, acidic soil and harsh environment of its native cliffs, where it finds few competitors. Its isolated situation on these cliffs protects it from most threats, but quarrying and mining of the cliffs, rock climbing, and other activities that disturb the cliff ecosystem can destroy it. (Full article...)
A. brownii was first discovered during the Tanager Expedition in 1923 by botanist Edward Leonard Caum. It differed from other Hawaiian species of Amaranthus with its spineless leaf axils, linear leaves, and indehiscent fruits. It was one of 26 vascular plants on Nihoa, 17 of which are indigenous, six alien, and three endemic only to Nihoa; these latter three included A. brownii, the Nihoa fan palm or loulu, and the Nihoa carnation. A. brownii was considered the rarest plant on Nihoa and was not directly observed on the island after 1983. Past expeditions collected plant samples and seeds, but no specimens managed to survive ex situ conservation efforts outside of its native habitat. Consequently, there are no known plants or seeds from A. brownii in any botanical garden. (Full article...)
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Carex binervis, the green-ribbed sedge, is a European species of sedge with an Atlantic distribution. It is found from Fennoscandia to the Iberian Peninsula, and occurs in heaths, moorland and other damp, acidic environments. It typically grows to a height of 15–120 cm (6–50 in), and has inflorescences comprising one male and several female spikes, each up to 45 mm (1.8 in) long. The utricles have two conspicuous green veins, which give rise to both the scientific name and the common name of the species. In the vegetative state, it closely resembles C. bigelowii, a species that usually grows at higher altitude. C. binervis was first described by James Edward Smith in 1800, and is classified in Carex sect. Spirostachyae; several hybrids with other Carex species are known. (Full article...)
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In Slavic folklore, the raskovnik or razkovniche (SerbianCyrillic and Macedonian: расковник; Bulgarian: разковниче[rɐsˈkɔvnit͡ʃɛ]; Russian: разрыв-трава; Polish: rozryw) is a magical herb. According to lore, the raskovnik has the magical property to unlock or uncover anything that is locked or closed. However, legends claim it is notoriously difficult to recognize the herb, and reputedly only certain chthonic animals are able to identify it. (Full article...)
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Characteres generum plantarum (complete title Characteres generum plantarum, quas in Itinere ad Insulas Maris Australis, Collegerunt, Descripserunt, Delinearunt, annis MDCCLXXII-MDCCLXXV Joannes Reinoldus Forster et Georgius Forster, "Characteristics of the types of plants collected, described, and delineated during a voyage to islands of the South Seas, in the years 1772–1775 by Johann Reinhold Forster and Georg Forster") is a 1775/1776 book by Johann Reinhold Forster and Georg Forster about the botanical discoveries they made during the second voyage of James Cook.
The book contains 78 plates, the majority of which depict dissections of flowers at natural size. The book introduced 94 binomial names from 75 genera, of which 43 are still the accepted names today. Many plant genera were named after friends or patrons of the Forsters. The book was published in a folio and a quarto edition and translated into German in 1779. It is an important book as the earliest publication of names and descriptions of the native species of New Zealand. (Full article...)
Asplenium montanum, commonly known as the mountain spleenwort, is a small fern endemic to the eastern United States. It is found primarily in the Appalachian Mountains from Vermont to Alabama, with a few isolated populations in the Ozarks and in the Ohio Valley. It grows in small crevices in sandstone cliffs with highly acid soil, where it is usually the only vascular plant occupying that ecological niche. It can be recognized by its tufts of dark blue-green, highly divided leaves. The species was first described in 1810 by the botanist Carl Ludwig Willdenow. No subspecies have been described, although a discolored and highly dissected form was reported from the Shawangunk Mountains in 1974. Asplenium montanum is a diploid member of the "Appalachian Asplenium complex," a group of spleenwort species and hybrids which have formed by reticulate evolution. Members of the complex descended from A. montanum are among the few other vascular plants that can tolerate its typical habitat. (Full article...)
... that ochrophyte algae have twice as many membranes around their chloroplasts as plants?
... that plant biology professor Luca Comai independently developed glyphosate-resistant plants while working at Calgene and published his research before Monsanto researchers were able to?
... that according to Lois N. Magner, Hildegard of Bingen's Physica is "probably the first book by a female author to discuss the elements and the therapeutic virtues of plants, animals, and metals"?
Image 4Echeveria glauca in a Connecticut greenhouse. Botany uses Latin names for identification; here, the specific name glauca means blue. (from Botany)
Image 5This is an electron micrograph of the epidermal cells of a Brassica chinensis leaf. The stomates are also visible. (from Plant cell)
Image 6The trunk of early tree fern Psaronius, showing internal structure. The top of the plant would have been to the left of the image (from Evolutionary history of plants)
Image 7The branching pattern of megaphyll veins may indicate their origin as webbed, dichotomising branches. (from Evolutionary history of plants)
Image 8A late Siluriansporangium, artificially colored. Green: A spore tetrad. Blue: A spore bearing a trilete mark – the Y-shaped scar. The spores are about 30–35 μm across. (from Evolutionary history of plants)
Image 9Structure of a plant cell (from Plant cell)
Image 12Thale cress, Arabidopsis thaliana, the first plant to have its genome sequenced, remains the most important model organism. (from Botany)
Image 13A banded tube from the Late Silurian/Early Devonian. The bands are difficult to see on this specimen, as an opaque carbonaceous coating conceals much of the tube. Bands are just visible in places on the left half of the image. Scale bar: 20 μm (from Evolutionary history of plants)
Image 14Transverse section of a fossil stem of the Devonian vascular plant Rhynia gwynne-vaughani (from Botany)
Image 15A botanist preparing a plant specimen for mounting in the herbarium (from Botany)
Image 24The fruit of Myristica fragrans, a species native to Indonesia, is the source of two valuable spices, the red aril (mace) enclosing the dark brown nutmeg. (from Botany)
Image 28The Linnaean Garden of Linnaeus' residence in Uppsala, Sweden, was planted according to his Systema sexuale. (from Botany)
Image 29The evolution of syncarps. a: sporangia borne at tips of leaf b: Leaf curls up to protect sporangia c: leaf curls to form enclosed roll d: grouping of three rolls into a syncarp (from Evolutionary history of plants)
Image 30Five of the key areas of study within plant physiology (from Botany)
Image 31Structure of Azadirachtin, a terpenoid produced by the Neem plant, which helps ward off microbes and insects. Many secondary metabolites have complex structures (from Evolutionary history of plants)
Image 34The Devonian marks the beginning of extensive land colonization by plants, which – through their effects on erosion and sedimentation – brought about significant climatic change. (from Evolutionary history of plants)
Image 351 An oat coleoptile with the sun overhead. Auxin (pink) is evenly distributed in its tip. 2 With the sun at an angle and only shining on one side of the shoot, auxin moves to the opposite side and stimulates cell elongation there. 3 and 4 Extra growth on that side causes the shoot to bend towards the sun. (from Botany)
Image 36The food we eat comes directly or indirectly from plants such as rice. (from Botany)