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 eat plants directly or rely on organisms which do so. (Full article...)
Aiphanes is a genus of spinypalms which is native to tropical regions of South and Central America and the Caribbean. There are about 26 species in the genus (see below), ranging in size from understorey shrubs with subterranean stems to subcanopy trees as tall as 20 metres (66 ft). Most have pinnately compound leaves (leaves which are divided into leaflets arranged feather-like, in pairs along a central axis); one species has entire leaves. Stems, leaves and sometimes even the fruit are covered with spines. Plants flower repeatedly over the course of their lifespan and have separate male and female flowers, although these are borne together on the same inflorescence. Although records of pollinators are limited, most species appear to be pollinated by insects. The fruit are eaten by several birds and mammals, including at least two species of amazon parrots.
Carl Ludwig Willdenow coined the name Aiphanes in 1801. Before that, species belonging to the genus had been placed in Bactris or Caryota. The name Martinezia had also been applied to the genus, and between 1847 and 1932 it was generally used in place of Aiphanes. Max Burret resurrected the name Aiphanes in 1932 and laid the basis for the modern concept of the genus. Aiphanes is most closely related to several other genera of spiny palms—Acrocomia, Astrocaryum, Bactris and Desmoncus. Two species are widely planted as ornamentals and the fruit, seeds or palm heart of several species have been eaten by indigenous peoples of the Americas for millennia. (Full article...)
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Cucurbita fruits come in an assortment of colors and sizes.
Cucurbita (Latin for 'gourd') is a genus of herbaceousfruits in the gourd family, Cucurbitaceae (also known as cucurbits or cucurbi), native to the Andes and Mesoamerica. Five edible species are grown and consumed for their flesh and seeds. They are variously known as squash, pumpkin, or gourd, depending on species, variety, and local parlance. Other kinds of gourd, also called bottle-gourds, are native to Africa and belong to the genus Lagenaria, which is in the same family and subfamily as Cucurbita, but in a different tribe; their young fruits are eaten much like those of the Cucurbita species.
Most Cucurbita species are herbaceous vines that grow several meters in length and have tendrils, but non-vining "bush" cultivars of C. pepo and C. maxima have also been developed. The yellow or orange flowers on a Cucurbita plant are of two types: female and male. The female flowers produce the fruit and the male flowers produce pollen. Many North and Central American species are visited by specialist beepollinators, but other insects with more general feeding habits, such as honey bees, also visit. (Full article...)
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The flora of Madagascar consists of more than 12,000 species of plants, as well as a poorly known number of fungi and algae. Around 83% of Madagascar's vascular plants are found only on the island. These endemics include five plant families, 85% of the over 900 orchid species, around 200 species of palms, and such emblematic species as the traveller's tree, six species of baobab and the Madagascar periwinkle. The high degree of endemism is due to Madagascar's long isolation following its separation from the African and Indian landmasses in the Mesozoic, 150–160 and 84–91 million years ago, respectively. However, few plant lineages remain from the ancient Gondwanan flora; most extant plant groups immigrated via across-ocean dispersal well after continental break-up.
After its continental separation, Madagascar probably experienced a dry period, and tropical rainforest expanded only later in the Oligocene to Miocene when rainfall increased. Today, humid forests, including the lowland forests, are mainly found on the eastern plateau where abundant rainfall from the Indian Ocean is captured by an escarpment. A large part of the central highlands, in the sub-humid forests ecoregion, is today dominated by grasslands. They are widely seen as result of human landscape transformation but some may be more ancient. Grassland occurs in a mosaic with woodland and bushland, including tapia forest, and hard-leaved thickets on the high mountains. Dry forest and succulent woodland are found in the drier western part and grade into the unique spiny thicket in the southwest, where rainfall is lowest and the wet season shortest. Mangroves occur on the west coast, and a variety of wetland habitats with an adapted flora are found across the island. (Full article...)
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A field of iceberg lettuces in California
Lettuce (Lactuca sativa) is an annual plant of the family Asteraceae mostly grown as a leaf vegetable. The leaves are most often used raw in green salads, although lettuce is also seen in other kinds of food, such as sandwiches, wraps and soups; it can also be grilled. Its stem and seeds are sometimes used; celtuce (asparagus lettuce) is one variety grown for its stems, which are eaten either raw or cooked. In addition to its main use as a leafy green, it has also gathered religious and medicinal significance over centuries of human consumption. Europe and North America originally dominated the market for lettuce, but by the late 20th century the consumption of lettuce had spread throughout the world. As of 2021[update], world production of lettuce (and chicory) was 27 million tonnes, 53percent of which came from China.
Lettuce was originally farmed by the ancient Egyptians, who transformed it from a plant whose seeds were used to obtain oil into an important food crop raised for its succulent leaves and oil-rich seeds. Lettuce spread to the Greeks and Romans; the latter gave it the name lactuca, from which the English lettuce is derived. By 50 AD, many types were described, and lettuce appeared often in medieval writings, including several herbals. The 16th through 18th centuries saw the development of many varieties in Europe, and by the mid-18th century, cultivars were described that can still be found in modern gardens. (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...)
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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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Banksia telmatiaea, commonly known as swamp fox banksia or rarely marsh banksia, is a shrub that grows in marshes and swamps along the lower west coast of Australia. It grows as an upright bush up to 2 metres (6 feet 7 inches) tall, with narrow leaves and a pale brown flower spike, which can produce profuse quantities of nectar. First collected in the 1840s, it was not published as a separate species until 1981; as with several other similar species it was previously included in B. sphaerocarpa (fox banksia).
The shrub grows amongst scrubland in seasonally wet lowland areas of the coastal sandplain between Badgingarra and Serpentine in Western Australia. A little studied species, not much is known of its ecology or conservation biology. Reports suggest that a variety of birds and small mammals pollinate it. Like many members of the series Abietinae, it has not been considered to have much horticultural potential and is rarely cultivated. (Full article...)
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Margaret Sibella Brown (March 2, 1866 – November 16, 1961) was a Canadian amateur bryologist specializing in mosses and liverworts native to Nova Scotia. Early in her career she was involved with gathering supplies of sphagnum moss to be used as surgical dressings during World War I, when cotton was in short supply. After the war, she researched mosses from around the world, collecting specimens in Europe, the Caribbean, and the United States, as well as her native Canada. She published several papers in academic journals, some on materials she had collected herself and some cataloging samples collected by other investigators. Samples she collected are now housed at several major herbaria in North America and Europe.
Born into upper-class society, Brown was educated in Halifax, Stuttgart, and London. Although lacking formal scientific training, she has been recognized for her contributions to bryology and as an authority on the mosses and liverworts of Nova Scotia. At the age of 84, Brown was awarded an honorary M.A. degree from Acadia University after declining their offer of a Ph.D. She died at her home in Halifax in 1961 aged 95. In 2010, she was inducted into the Nova Scotia Scientific Hall of Fame. (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 southwest 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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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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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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Several plants in cultivation
Drosera regia, commonly known as the king sundew, is a carnivorous plant in the sundew genus Drosera that is endemic to a single valley in South Africa. Individual leaves can reach 70 cm (28 in) in length. It has many unusual relict characteristics not found in most other Drosera species, including woody rhizomes, operculatepollen, and the lack of circinate vernation in scape growth. All of these factors, combined with molecular data from phylogenetic analysis, contribute to the evidence that D. regia possesses some of the most ancient characteristics within the genus. Some of these are shared with the related Venus flytrap (Dionaea muscipula), which suggests a close evolutionary relationship.
The tentacle-covered leaves can capture large prey, such as beetles, moths, and butterflies. The tentacles of all Drosera species have special stalked glands on the leaf's upper surface that produce a sticky mucilage. The leaves are considered active flypaper traps that respond to captured prey by bending to surround it. In its native fynbos habitat, the plants compete for space with native marsh grasses and low evergreenshrubs. Of the two known populations of D. regia, the higher elevation site appears to be overgrown and is essentially extirpated. The lower elevation site is estimated to have about 50 mature plants, making it the most endangered Drosera species, since it is threatened with extinction in the wild. It is often cultivated by carnivorous plant enthusiasts, and a single cultivar has been registered. (Full article...)
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Banksia dentata, commonly known as the tropical banksia, is a species of tree in the family Proteaceae. It occurs across northern Australia, southern New Guinea and the Aru Islands. Growing as a gnarled tree to 7 m (23 ft) high, it has large green leaves up to 22 cm (8.7 in) long with dentatemargins. The cylindrical yellow inflorescences, up to 13 cm (5.1 in) high, appear between November and May, attracting various species of honeyeaters, sunbirds, the sugar glider and a variety of insects. Flowers fall off the ageing spikes, which swell and develop follicles containing up to two viable seeds each.
Banksia dentata is one of four Banksia species collected by Sir Joseph Banks in 1770, and one of the four species published in 1782 as part of Carolus Linnaeus the Younger's original description of Banksia. Within the genus, it is classified in the seriesSalicinae, a group of species from Australia's eastern states. Genetic studies show it is a basal member within the group. Banksia dentata is found in tropical grassland known as savanna, and associated with Pandanus and Melaleuca. It regenerates from bushfire by regrowing from its woody base, known as a lignotuber. (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...)
The species was first collected by Humboldt and Bonpland on the outskirts of Mina de Morán in the Sierra de Pachuca of the modern-day Mexican state of Hidalgo on their Latin American expedition of 1799–1804. Based on these collections, Carl Sigismund Kunth described this species in Nova Genera et Species Plantarum in 1817. The extremely variable species has been redefined at least twice since, while several new species have been segregated from it based on various geographical or morphological distinctions, although the legitimacy of some of these is still debated. P. moranensis remains the most common and most widely distributed member of the Section Orcheosanthus. It has long been cultivated for its carnivorous nature and attractive flowers, and is one of the most common butterworts in cultivation. (Full article...)
The Chinese character for hemp (麻 or má) depicts two plants under a shelter. Notably, the same character also means "numb". Cannabis cultivation dates back at least 3000 years in Taiwan.
The history of cannabis and its usage by humans dates back to at least the third millennium BC in written history, and possibly as far back as the Pre-Pottery Neolithic B (8800–6500 BCE) based on archaeological evidence. For millennia, the plant has been valued for its use for fiber and rope, as food and medicine, and for its psychoactive properties for religious and recreational use.
The earliest restrictions on cannabis were reported in the Islamic world by the 14th century. In the 19th century, it began to be restricted in colonial countries, often associated with racial and class stresses. In the middle of the 20th century, international coordination led to sweeping restrictions on cannabis throughout most of the globe. Entering the 21st century, some nations began to take measures to decriminalize or legalize cannabis. (Full article...)
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An upper pitcher of Nepenthes lowii, a tropical pitcher plant that supplements its carnivorous diet with tree shrew droppings.
True carnivory is believed to have evolved independently at least 12 times in five different orders of flowering plants, and is represented by more than a dozen genera. This classification includes at least 583 species that attract, trap, and kill prey, absorbing the resulting available nutrients. Venus flytraps (Dionaea muscipula), pitcher plants, and bladderworts (Utricularia spp.) can be seen as exemplars of key traits genetically associated with carnivory: trap leaf development, prey digestion, and nutrient absorption. (Full article...)
NYBG is also a major educational institution, teaching visitors about plant science, ecology, and healthful eating through NYBG's interactive programming. Nearly 90,000 of the annual visitors are children from underserved neighboring communities. An additional 3,000 are teachers from New York City's public school system participating in professional development programs that train them to teach science courses at all grade levels. NYBG operates one of the world's largest plant research and conservation programs. (Full article...)
White tea, yellow tea, green tea, oolong, dark tea (which includes pu-erh tea) and black tea are all harvested from one of two major varieties grown today, C. sinensis var. sinensis and C. s. var. assamica, but are processed differently to attain varying levels of oxidation with black tea being the most oxidized and white being the least. Kukicha (twig tea) is also harvested from C. sinensis, but uses twigs and stems rather than leaves. (Full article...)
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Bee pollinating a flower 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...)
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Jelena de Belder-Kovačič (23 August 1925 – 31 August 2003) was a Slovenian-Belgian botanist and horticulturist, who worked extensively on the taxonomy and preservation of plant specimens, gaining an international reputation for her development of the Kalmthout and Hemelrijk Arboreta. Several varieties of plants she cultivated were recognized with awards from the Royal Horticultural Society in London and she was elevated to Baroness by Albert II of Belgium for her contributions to dendrology. (Full article...)
Untended, overgrown plants can escape by rooting elsewhere (English ivy) An escaped plant is a cultivated plant that has escaped from agriculture, forestry or garden cultivation and has become naturalized in the wild. Usually not native to an area, escaped plants may become invasive. Therefore, escaped plants are the subject of research in invasion biology.
Some ornamental plants have characteristics which allow them to escape cultivation and become weedy in alien ecosystems with far-reaching ecological and economic consequences. Escaped garden plants may be called garden escapes or escaped ornamentals. Sometimes, their origins can even be traced back to botanical gardens. (Full article...)
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The hybrid tea rose, 'Peace' Garden roses are predominantly hybridroses that are grown as ornamental plants in private or public gardens. They are one of the most popular and widely cultivated groups of flowering plants, especially in temperate climates. An enormous number of garden cultivars has been produced, especially over the last two centuries, though roses have been known in the garden for millennia beforehand. While most garden roses are grown for their flowers, often in dedicated rose gardens, some are also valued for other reasons, such as having ornamental fruit, providing ground cover, or for hedging.
The cultivars are classified in a number of different and overlapping ways, generally without much reference to strict botanical principles. Taking overall size and shape, the most common type is the bush rose, a rounded plant from 2 foot up to about 7 foot tall, above which height roses generally fall into the "'climbing and rambling'" class, the latter spreading wider; support is needed for these. There are also miniature roses, generally small bushes, and low sprawling ground cover roses, both up to about 15 inches tall. Most modern roses are propagated by budding onto rootstocks much closer to wild species; in "standard" shapes there is a single bare stem, with the graft at the top of that. Shrub roses are a rather loose category that include some of the original species and cultivars closely related to them, plus cultivars that grow rather larger than most bush roses. Technically all roses are shrubs. In terms of ancestry, roses are often divided into three main groups: Wild, Old Garden, and Modern Garden roses, with many subdivisions of these. (Full article...)
Mendel worked with seven characteristics of pea plants: plant height, pod shape and color, seed shape and color, and flower position and color. Taking seed color as an example, Mendel showed that when a true-breeding yellow pea and a true-breeding green pea were cross-bred, their offspring always produced yellow seeds. However, in the next generation, the green peas reappeared at a ratio of 1 green to 3 yellow. To explain this phenomenon, Mendel coined the terms "recessive" and "dominant" in reference to certain traits. In the preceding example, the green trait, which seems to have vanished in the first filial generation, is recessive, and the yellow is dominant. He published his work in 1866, demonstrating the actions of invisible "factors"—now called genes—in predictably determining the traits of an organism. The actual genes were only discovered in a long process that ended in 2025 when the last three of the seven Mendel genes were identified in the pea genome. (Full article...)
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Various gymnosperms.
The gymnosperms (/ˈdʒɪmnəˌspɜːrmz,-noʊ-/ⓘnə-spurmz, -noh-; lit.'revealed seeds') are a group of woody, perennial seed-producing plants, typically lacking the protective outer covering which surrounds the seeds in flowering plants, that include conifers, cycads, Ginkgo, and gnetophytes, forming the clade Gymnospermae. The term gymnosperm comes from the composite word in Greek: γυμνόσπερμος (γυμνός, gymnos, 'naked' and σπέρμα, sperma, 'seed'), and literally means 'naked seeds'. The name is based on the unenclosed condition of their seeds (called ovules in their unfertilized state). The non-encased condition of their seeds contrasts with the seeds and ovules of flowering plants (angiosperms), which are enclosed within an ovary. Gymnosperm seeds develop either on the surface of scales or leaves, which are often modified to form cones, or on their own as in yew, Torreya, and Ginkgo.
The life cycle of a gymnosperm involves alternation of generations, with a dominant diploidsporophyte phase, and a reduced haploidgametophyte phase, which is dependent on the sporophytic phase. The term "gymnosperm" is often used in paleobotany to refer to (the paraphyletic group of) all non-angiosperm seed plants. In that case, to specify the modern monophyletic group of gymnosperms, the term Acrogymnospermae is sometimes used. (Full article...)
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Maize (Zea mays, Poaceae) is the most widely cultivated C4 plant.
In botany, C4 carbon fixation is one of three known methods of photosynthesis used by plants. C4 plants increase their photosynthetic efficiency by reducing or suppressing photorespiration, which mainly occurs under low atmospheric CO2 concentration, high light, high temperature, drought, and salinity. There are roughly 8,100 known C4 species, which belong to at least 61 distinct evolutionary lineages in 19 families (as per APG IV classification) of flowering plants. Among these are important crops such as maize, sorghum and sugarcane, but also weeds and invasive plants. Although only 3% of flowering plant species use C4 carbon fixation, they account for 23% of global primary production. The repeated, convergent C4 evolution from C3 ancestors has spurred hopes to bio-engineer the C4 pathway into C3 crops such as rice. C4 photosynthesis probably first evolved 30–35 million years ago in the Oligocene, and further origins occurred since, most of them in the last 15 million years. C4 plants are mainly found in tropical and warm-temperate regions, predominantly in open grasslands where they are often dominant. While most are graminoids, other growth forms such as forbs, vines, shrubs, and even some trees and aquatic plants are also known among C4 plants. (Full article...)
Diagram illustrating the process of pollination Pollination is the transfer of pollen from an anther of a plant to the stigma of a plant, later enabling fertilisation and the production of seeds. Pollinating agents can be animals such as insects, for example bees, beetles or butterflies; birds, and bats; water; wind; and even plants themselves. Pollinating animals travel from plant to plant carrying pollen on their bodies in a vital interaction that allows the transfer of genetic material critical to the reproductive system of most flowering plants. Self-pollination occurs within a closed flower. Pollination often occurs within a species. When pollination occurs between species, it can produce hybrid offspring in nature and in plant breeding work.
In angiosperms, after the pollen grain (gametophyte) has landed on the stigma, it germinates and develops a pollen tube which grows down the style until it reaches an ovary. Its two gametes travel down the tube to where the gametophyte(s) containing the female gametes are held within the carpel. After entering an ovule through the micropyle, one male nucleus fuses with the polar bodies to produce the endospermtissues, while the other fuses with the egg cell to produce the embryo. Hence the term: "double fertilisation". This process would result in the production of a seed, made of both nutritious tissues and embryo. (Full article...)
Broccoli, a plant of the Cabbage family, Brassicaceae, is a cool-weather crop eaten boiled, steamed, or raw. The Roman natural history writer, Pliny the Elder, wrote about a vegetable which might have been broccoli and some recognize broccoli in the cookbook of Apicius, but its history is unclear. Broccoli was certainly an Italian vegetable long before it was eaten elsewhere.
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In mathematics, the three-gap theorem, three-distance theorem, or Steinhaus conjecture states that if one places n points on a circle, at angles of θ, 2θ, 3θ, ... from the starting point, then there will be at most three distinct distances between pairs of points in adjacent positions around the circle. When there are three distances, the largest of the three always equals the sum of the other two. Unless θ is a rational multiple of π, there will also be at least two distinct distances.
This result was conjectured by Hugo Steinhaus, and proved in the 1950s by Vera T. Sós, János Surányi [hu], and Stanisław Świerczkowski; more proofs were added by others later. Applications of the three-gap theorem include the study of plant growth and musical tuning systems, and the theory of light reflection within a mirrored square. (Full article...)
The lily family, Liliaceae, consists of about 15 genera and 610 species of flowering plants within the orderLiliales. They are monocotyledonous, perennial, herbaceous, often bulbousgeophytes. Plants in this family have evolved with a fair amount of morphological diversity despite genetic similarity. Common characteristics include large flowers with parts arranged in threes: with six colored or patterned petaloidtepals (undifferentiated petals and sepals) arranged in two whorls, six stamens and a superior ovary. The leaves are linear in shape, with their veins usually arranged parallel to the edges, single and arranged alternating on the stem, or in a rosette at the base. Most species are grown from bulbs, although some have rhizomes. First described in 1789, the lily family became a paraphyletic "catch-all" (wastebasket) group of lilioid monocots that did not fit into other families and included a great number of genera now included in other families and in some cases in other orders. Consequently, many sources and descriptions labelled "Liliaceae" deal with the broader sense of the family.
The family evolved approximately 68 million years ago during the Late Cretaceous to Early Paleogene epochs. Liliaceae are widely distributed, mainly in temperate regions of the Northern Hemisphere and the flowers are insect pollinated. Many Liliaceae are important ornamental plants, widely grown for their attractive flowers and involved in a major floriculture of cut flowers and dry bulbs. Some species are poisonous if eaten and can have adverse health effects in humans and household pets. (Full article...)
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Piper cubeba, cubeb or tailed pepper is a plant in genusPiper, cultivated for its fruit and essential oil. It is mostly grown in Java and Sumatra, hence sometimes called Java pepper. The fruits are gathered before they are ripe, and carefully dried. Commercial cubeb consists of the dried berries, similar in appearance to black pepper, but with stalks attached – the "tails" in "tailed pepper". The dried pericarp is wrinkled, and its color ranges from grayish brown to black. The seed is hard, white and oily. The odor of cubeb is described as agreeable and aromatic and the taste as pungent, acrid, slightly bitter and persistent. It has been described as tasting like allspice, or like a cross between allspice and black pepper.
Cubeb came to Europe via India through the trade with the Arabs. The name cubeb comes from Arabickabāba (كبابة) by way of Old Frenchquibibes. Cubeb is mentioned in alchemical writings by its Arabic name. In his Theatrum Botanicum, John Parkinson tells that the king of Portugal (Possibly either Philip IV of Spain or John IV of Portugal, as that year was marked by the start of the Portuguese Restoration War) prohibited the sale of cubeb to promote black pepper (Piper nigrum) around 1640. It experienced a brief resurgence in 19th-century Europe for medicinal uses, but has practically vanished from the European market since. It continues to be used as a flavoring agent for gins and cigarettes in the West, and as a seasoning for food in Indonesia. (Full article...)
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Cabbage tree on farmland, South Island, New Zealand
Cordyline australis, commonly known as the cabbage tree, or by its Māori name of tī or tī kōuka, is a widely branched monocot tree endemic to New Zealand.
It grows up to 20 metres (66 feet) tall with a stout trunk and sword-like leaves, which are clustered at the tips of the branches and can be up to 1 metre (3 feet 3 inches) long. With its tall, straight trunk and dense, rounded heads, it is a characteristic feature of the New Zealand landscape. It is common over a wide latitudinal range from the far north of the North Island to the south of the South Island. It grows in a broad range of habitats. The largest known tree, growing at Pākawau, Golden Bay / Mohua, is estimated to be 400 or 500 years old, and stands 17 metres (56 feet) tall with a circumference of 9 metres (30 feet) at the base. (Full article...)
The book is organised chronologically and mainly describes the voyage from England to Tahiti, the time spent there, and the encounters with New Zealand and Australia. It contains Parkinson's vocabularies of several Pacific languages and also many plant names given by Daniel Solander, but most of these have not been accepted as botanical names. The book is illustrated by engravings based on Sydney Parkinson's drawings. It has been praised for its authenticity but criticised by botanists for the low quality of the botanical content. (Full article...)
Selection against the weed may occur by killing a young or adult weed, by separating its seeds from those of the crop by winnowing, or both. The process has operated since Neolithic times, creating secondary crops such as rye and oats through mimicry of cereals such as wheat. (Full article...)
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The carrot (Daucus carota subsp. sativus) is a root vegetable, typically orange in colour, though heirloom variants including purple, black, red, white, and yellow cultivars exist, all of which are domesticated forms of the wild carrot, Daucus carota, native to Europe and Southwestern Asia. The plant probably originated in Iran and was originally cultivated for its leaves and seeds.
Cicuta, commonly known as water hemlock, is a genus of four species of highly poisonous plants in the family Apiaceae. They are perennialherbaceous plants which grow up to 2.5 meters (8 ft) tall, having distinctive small green or white flowers arranged in an umbrella shape (umbel). Plants in this genus may also be referred to as cowbane or poison parsnip. Cicuta is native to temperate regions of the Northern Hemisphere, mainly North America and Europe, typically growing in wet meadows, along streambanks and other wet and marshy areas. These plants bear a close resemblance to other members in the family Apiaceae and may be confused with a number of edible or poisonous plants. The common name hemlock may also be confused with poison hemlock (Conium maculatum), or with the Hemlock tree.
Water hemlock is considered one of North America's most toxic plants, being highly poisonous to humans. Three members of the genus contain a toxin named cicutoxin which causes central nervous system stimulatory effects including seizures following ingestion. Medical treatment of poisoning may include the use of activated charcoal to decrease gastrointestinal absorption of the toxic principle along with supportive care including anticonvulsant drugs such as a benzodiazepine. High doses of anticonvulsant medicine are often required to halt seizure activity and further medical care including intubation and mechanical ventilation may be required. (Full article...)
Dracophyllum traversii, commonly known as mountain neinei, grass tree, and pineapple tree is a species of flowering plant in the heath family Ericaceae. It is a deciduous tree (or, in some cases, a shrub) endemic to New Zealand. It reaches a height of 0.2–13 m (0.66–42.65 ft) and has leaves which form tufts at the end of its branches. It has a lifespan of between 500 and 600 years.
Similar to some other Dracophyllum species, it has a candelabra-shaped canopy; long, thin, green leaves; and a prominent pyramid-shaped inflorescence. It has tiny red flowers, between 500 and 3000 on each panicle, and equally tiny reddish-brown dry fruit. D. traversii inhabits a variety of forest and shrubland types, from lowland to subalpine, in gorges, on cliffs, and on mountainsides. It has a range that stretches from Waima forest at the top of New Zealand's North Island, down to Otago and Fiordland in the South Island. (Full article...)
The taxonomy of Narcissus is complex, and still not fully resolved. Known to the ancients, the genus name appears in Graeco-Roman literature, although their interest was as much medicinal as botanical. It is unclear which species the ancients were familiar with. Although frequently mentioned in Mediaeval and Renaissance texts it was not formally described till the work of Linnaeus in 1753. By 1789 it had been grouped into a family (Narcissi) but shortly thereafter this was renamed Amaryllideae, from which comes the modern placement within Amaryllidaceae, although for a while it was considered part of Liliaceae.
Many of the species now considered to be Narcissus were in separate genera during the nineteenth century, and the situation was further confused by the inclusion of many cultivated varieties. By 1875 the current circumscription was relatively settled. By 2004 phylogenetic studies had allowed the place of Narcissus within its fairly large family to be established, nested within a series of subfamilies (Amaryllidoideae) and tribes (Narcisseae). It shares its position in the latter tribe with Sternbergia. (Full article...)
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Betula pendula, commonly known as silver birch, warty birch, European white birch, or East Asian white birch, is a species of tree in the familyBetulaceae, native to Europe and parts of Asia, though in southern Europe, it is only found at higher altitudes. Its range extends into Siberia, China, and southwest Asia in the mountains of northern Turkey, the Caucasus, and northern Iran. It has been introduced into North America, where it is known as the European white birch or weeping birch and is considered invasive in some states in the United States and parts of Canada.
The silver birch is a medium-sized deciduous tree that owes its common name to the white peeling bark on the trunk. The twigs are slender and often pendulous and the leaves are roughly triangular with doubly serrate margins and turn yellow and brown in autumn before they fall. The flowers are catkins and the light, winged seeds get widely scattered by the wind. The silver birch is a hardy tree, a pioneer species, and one of the first trees to appear on bare or fire-swept land. Many species of birds and animals are found in birch woodland, the tree supports a wide range of insects and the light shade it casts allows shrubby and other plants to grow beneath its canopy. It is planted decoratively in parks and gardens and is used for forest products such as joinery timber, firewood, tanning, racecourse jumps, and brooms. Various parts of the tree are used in traditional medicine and the bark contains triterpenes, which have been shown to have medicinal properties. (Full article...)
Born in Kitzingen, Fehr studied medicine at several universities, including the University of Padua, where he earned his doctorate in 1641. He co-founded the Leopoldina in 1652, and served as its second president, during which time the academy received official recognition from Leopold I in 1672. Fehr also worked as a doctor in Schweinfurt and briefly served as its mayor before his death in 1688. (Full article...)
... that police officers had to be flown in by helicopter to seize hundreds of thousands of dollars' worth of cannabis plants found growing illegally in Jerrawangala National Park?
... that Aristotle classified living things based on whether they had a "sensitive soul" or, like plants, only a "vegetative soul"?
... that while most lichens that grow on plants live on the surface, the sole species in Amazonotrema grows partially among the cells of the tree bark on which it lives?
Image 5Structure 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 61 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 7Echeveria glauca in a Connecticut greenhouse. Botany uses Latin names for identification; here, the specific name glauca means blue. (from Botany)
Image 14A 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 17Paper chromatography of some spinach leaf extract shows the various pigments present in their chloroplasts: yellowish xanthophylls, greenish chlorophylls a and b. (from Botany)
Image 19A botanist preparing a plant specimen for mounting in the herbarium (from Botany)
Image 20The 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 21A nineteenth-century illustration showing the morphology of the roots, stems, leaves and flowers of the rice plant Oryza sativa (from Botany)
Image 22Thale cress, Arabidopsis thaliana, the first plant to have its genome sequenced, remains the most important model organism. (from Botany)
Image 23A 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 24Five of the key areas of study within plant physiology (from Botany)
Image 29Leaf lamina. The megaphyllous leaf architecture arose multiple times in different plant lineages (from Evolutionary history of plants)
Image 30The 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 31The 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 32The 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)