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...)
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Adenanthos obovatus, commonly known as basket flower (which usually refers to Centaurea, though), or, jugflower, is a shrub of the plantfamilyProteaceaeendemic to Southwest Australia. Described by French naturalist Jacques Labillardière in 1805, it had first been collected by Archibald Menzies in 1791. Within the genus Adenanthos, it lies in the sectionEurylaema and is most closely related to A. barbiger. A. obovatus has hybridized with A. detmoldii to produce the hybrid A. × pamela. Several common names allude to the prominent red flowers of the species. It grows as a many-stemmed spreading bush up to 1 m (3.3 ft) high, and about 1.5 m (4.9 ft) across, with fine bright green foliage. Made up of single red flowers, the inflorescences appear from April to December, and peak in spring (August to October).
The shrub grows on sandy soils in seasonally wet lowland areas as well as hills and dunes. It regenerates after bushfire by resprouting from its underground lignotuber. Pollinators include honeyeaters, particularly the western spinebill, which can access the nectar with its long curved bill, and the silvereye, which punctures the flower tube. The most commonly cultivated Adenanthos species in Australia, it has a long flowering period and attracts honeyeaters to the garden. It is harvested for the cut flower industry. (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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The title page of the 1877 edition of Fertilisation of Orchids
Fertilisation of Orchids is a book by English naturalist Charles Darwin published on 15 May 1862 under the full explanatory title On the Various Contrivances by Which British and Foreign Orchids Are Fertilised by Insects, and On the Good Effects of Intercrossing. Darwin's previous book, On the Origin of Species, had briefly mentioned evolutionary interactions between insects and the plants they fertilised, and this new idea was explored in detail. Field studies and practical scientific investigations that were initially a recreation for Darwin—a relief from the drudgery of writing—developed into enjoyable and challenging experiments. Aided in his work by his family, friends, and a wide circle of correspondents across Britain and worldwide, Darwin tapped into the contemporary vogue for growing exotic orchids.
The book was his first detailed demonstration of the power of natural selection, and explained how complex ecological relationships resulted in the coevolution of orchids and insects. The view has been expressed that the book led directly or indirectly to all modern work on coevolution and the evolution of extreme specialisation. It influenced botanists, and revived interest in the neglected idea that insects played a part in pollinating flowers. It opened up the new study areas of pollination research and reproductive ecology, directly related to Darwin's ideas on evolution, and supported his view that natural selection led to a variety of forms through the important benefits achieved by cross-fertilisation. Although the general public showed less interest and sales of the book were low, it established Darwin as a leading botanist. Orchids was the first in a series of books on his innovative investigations into plants. (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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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...)
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Second-year plant starting to flower, with a dead stem of the previous year, behind left
Verbascum thapsus, the great mullein, greater mullein or common mullein, is a species of mullein native to Europe, northern Africa, and Asia, and introduced in the Americas and Australia.
It is a hairy biennial plant that can grow to 2 m tall or more. Its small, yellow flowers are densely grouped on a tall stem, which grows from a large rosette of leaves. It grows in a wide variety of habitats, but prefers well-lit, disturbed soils, where it can appear soon after the ground receives light, from long-lived seeds that persist in the soil seed bank. It is a common weedy plant that spreads by prolifically producing seeds, and has become invasive in temperate world regions. It is a minor problem for most agricultural crops, since it is not a competitive species, being intolerant of shade from other plants and unable to survive tilling. It also hosts many insects, some of which can be harmful to other plants. Although individuals are easy to remove by hand, populations are difficult to eliminate permanently. (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...)
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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...)
While at the bookshop, he was offered a position as a librarian at the Royal Horticultural Society in London (1933–1952). From there he moved to the Natural History Museum as a scientific officer in the botany department (1952–1976). After his retirement, he continued working there, writing, and serving on a number of professional bodies related to his work, including the Linnean Society, of which he became president. He also taught botany at Cambridge University as a visiting professor (1977–1983). (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...)
Banksia violacea, commonly known as violet banksia, is a species of shrub or tree in the plant genus Banksia (family Proteaceae). It generally grows as a small shrub to 1.5 m (5 ft) high with fine narrow leaves, and is best known for its unusually coloured dark purple-violet inflorescences. The colour of the inflorescences, short leaves, and flattened follicles which are sticky when young, help identify this species from others in the field. It is found in low shrubland in southern regions of Western Australia from Esperance in the east to Narrogin in the west, growing exclusively in sandy soils.
First described in 1927 by the West Australian botanist Charles Gardner, the species was at one stage considered a variety of B. sphaerocarpa. Although there are no recognised subspecies or varieties, both lignotuberous and nonlignotuberous forms exist for Banksia violacea. Wasps, ants and flies have been recorded visiting flower spikes. Banksia violacea is classified as Not Threatened under the Wildlife Conservation Act of Western Australia. Regarded as of little value to floriculture, it is rarely cultivated. (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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Dracophyllum fiordense, commonly known as the Fiordland grass tree, is a species of tree or shrub in the heath family, Ericaceae. It is endemic to the South Island of New Zealand. It reaches a height of 1.5–5.0 metres (5–16 feet) and has tufts of long green leaves at the ends of its branches. Each leaf has a distinctive curled spiral tip. D. fiordense has a pyramid-shaped inflorescence (flower spike) hidden under each clump of leaves, with between 113 and 120 pink flowers on each spike, and later reddish-brown dry fruit; both are around just 2 by 2 mm. It inhabits shrubland, lowland and subalpine forests, and tussock grassland of mountain slopes, gullies, and ridges. Its range covers two main areas: one in Fiordland National Park, and one in the Mount Cook and Westland National Parks.
D. fiordense was first described by the New Zealand naturalist Walter Oliver in 1928 and placed by him in the subgenus Dracophyllum. A cladistic analysis using genetic sequencing was published in 2010, which revealed that D. fiordense is closely related to D. menziesii as Oliver had hypothesised. Its conservation status was assessed in 2017 as "Declining". The kākāpō, a flightless bird, feeds on the bases of the leaves by making careful incisions in new shoots. D. fiordense is likely pollinated by insects and its seeds are later dispersed by the wind. (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...)
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Banksia cuneata, commonly known as matchstick banksia or Quairading banksia, is an endangered species of flowering plant in the family Proteaceae. Endemic to southwestWestern Australia, it belongs to Banksia subg. Isostylis, a sub-genus of three closely related Banksia species with inflorescences or flower clusters that are dome-shaped heads rather than characteristic Banksia flower spikes. A shrub or small tree up to 5 m (16 ft) high, it has prickly foliage and pink and cream flowers. The common name Matchstick Banksia arises from the blooms in late bud, the individual buds of which resemble matchsticks. The species is pollinated by honeyeaters (Meliphagidae).
Although B. cuneata was first collected before 1880, it was not until 1981 that Australian botanist Alex George formally described and named the species. There are two genetically distinct population groups, but no recognised varieties. This Banksia is classified as endangered, surviving in fragments of remnant bushland in a region which has been 93% cleared for agriculture. As Banksia cuneata is killed by fire and regenerates from seed, it is highly sensitive to bushfire frequency—fires recurring within four years could wipe out populations of plants not yet mature enough to set seed. Banksia cuneata is rarely cultivated, and its prickly foliage limits its utility in the cut flower industry. (Full article...)
In horticulture, the term (per- + -ennial, "through the year") is used to differentiate a plant from shorter-lived annuals and biennials. It has thus been defined as a plant that lives more than two years. The term is also loosely used to distinguish plants with little or no woody growth (secondary growth in girth) from trees and shrubs, which are also technically perennials. Notably, it is estimated that 94% of plant species fall under the category of perennials, underscoring the prevalence of plants with lifespans exceeding two years in the botanical world.
Perennials (especially small flowering plants) that grow and bloom over the spring and summer, die back every autumn and winter, and then return in the spring from their rootstock or other overwintering structure, are known as herbaceous perennials. However, depending on the rigours of the local climate (temperature, moisture, organic content in the soil, microorganisms), a plant that is a perennial in its native habitat, may be treated by a gardener as an annual and planted out every year, from seed, from cuttings, or from divisions. Tomato vines, for example, live several years in their natural tropical/ subtropical habitat but are grown as annuals in temperate regions because their above-ground biomass does not survive the winter. (Full article...)
Among all living organisms, flowers, which are the reproductive structures of angiosperms, are the most varied physically and show a correspondingly great diversity in methods of reproduction. Plants that are not flowering plants (green algae, mosses, liverworts, hornworts, ferns and gymnosperms such as conifers) also have complex interplays between morphological adaptation and environmental factors in their sexual reproduction. The breeding system, or how the sperm from one plant fertilizes the ovum of another, depends on the reproductive morphology, and is the single most important determinant of the genetic structure of nonclonal plant populations. Christian Konrad Sprengel (1793) studied the reproduction of flowering plants and for the first time it was understood that the pollination process involved both biotic and abiotic interactions. Charles Darwin's theories of natural selection utilized this work to build his theory of evolution, which includes analysis of the coevolution of flowers and their insectpollinators. (Full article...)
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Jane Colden (March 27, 1724 – March 10, 1766) was an American botanist, described as the "first botanist of her sex in her country" by Asa Gray in 1843. Although not acknowledged in contemporary botanical publications, she wrote a number of letters resulting in botanist John Ellis writing to Carl Linnaeus of her work applying the Linnaean system of plant identification to American flora, for which botanist Peter Collinson stated "she deserves to be celebrated". Contemporary scholarship maintains that she was the first female botanist working in America, which ignores, among others, Maria Sibylla Merian or Catherine Jérémie. Colden was respected as a botanist by many prominent botanists including John Bartram, Peter Collinson, Alexander Garden, and Carl Linnaeus. Colden is most famous for her untitled manuscript, housed in the British Museum, in which she describes the flora of the Hudson Valley in the Newburgh region of New York state, including ink drawings of 340 different species. (Full article...)
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A fine root is most commonly defined as a plant root that is two millimeters or less in diameter. Fine roots may function in acquisition of soil resources (eg. nutrients, water) and/or resource transport, making them functionally most analogous to the leaves and twigs in a plant's shoot system. Fine-root traits are variable between species and responsive to environmental conditions. Consequently, fine roots are studied to characterize the resource acquisition strategies and competitive ability of plant species. Categories of fine roots have been developed based on root diameter, position in a root system's branching hierarchy, and primary function. Fine roots are often associated with symbiotic fungi and play a role in many ecosystem processes like nutrient cycles and soil reinforcement. (Full article...)
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In botany, a berry is a fleshy fruit without a stone (pit) produced from a single flower containing one ovary. Berries so defined include grapes, currants, and tomatoes, as well as cucumbers, eggplants (aubergines), persimmons and bananas, but exclude certain fruits that meet the culinary definition of berries, such as strawberries and raspberries. The berry is the most common type of fleshy fruit in which the entire outer layer of the ovary wall ripens into a potentially edible "pericarp". Berries may be formed from one or more carpels from the same flower (i.e. from a simple or a compound ovary). The seeds are usually embedded in the fleshy interior of the ovary, but there are some non-fleshy exceptions, such as Capsicum species, with air rather than pulp around their seeds.
The genus has a highly disjunct distribution spread across two major groups of tepuis: the western range in Amazonas and the eastern range in Bolívar. The western range can be further subdivided into two complexes of neighbouring tepuis. The more southerly of these consists of Cerro de la Neblina, Cerro Aracamuni, and Cerro Avispa, and supports four Heliamphora species. The more northerly group of the western range, home to only two species, includes the massive Cerro Duida and neighbouring Cerro Huachamacari and Cerro Marahuaca. The remaining 17–19 species are native to the eastern range, which includes the Aprada Massif, Auyán Massif, Chimantá Massif, Eastern Tepuis chain, Los Testigos chain, and a number of outlying tepuis. Many of the summits of the eastern range are situated on a vast plateau known as the Gran Sabana. Only two species (H. ciliata and H. heterodoxa) are known with certainty from the Gran Sabana, and only H. ciliata is endemic to this habitat. (Full article...)
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Utricularia vulgaris illustration from Jakob Sturm's "Deutschlands Flora in Abbildungen", Stuttgart (1796)
Utricularia, commonly and collectively called the bladderworts, is a genus of carnivorous plants consisting of approximately 233 species (precise counts differ based on classification opinions; a 2001 publication lists 215 species). They occur in fresh water and wet soil as terrestrial or aquatic species across every continent except Antarctica. Utricularia are cultivated for their flowers, which are often compared with those of snapdragons and orchids, especially amongst carnivorous plant enthusiasts.
All Utricularia are carnivorous and capture small organisms by means of bladder-like traps. Terrestrial species tend to have tiny traps that feed on minute prey such as protozoa and rotifers swimming in water-saturated soil. The traps can range in size from 0.02 to 1.2 cm (0.008 to 0.5 in). Aquatic species, such as U. vulgaris (common bladderwort), possess bladders that are usually larger and can feed on more substantial prey such as water fleas (Daphnia), nematodes and even fish fry, mosquitolarvae and young tadpoles. Despite their small size, the traps are extremely sophisticated. In the active traps of the aquatic species, prey brush against trigger hairs connected to the trapdoor. The bladder, when "set", is under negative pressure in relation to its environment so that when the trapdoor is mechanically triggered, the prey, along with the water surrounding it, is sucked into the bladder. Once the bladder is full of water, the door closes again, the whole process taking only ten to fifteen milliseconds. (Full article...)
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Taraxacum (/təˈræksəkəm/) is a large genus of flowering plants in the family Asteraceae, which consists of species commonly known as dandelions. The scientific and hobby study of the genus is known as taraxacology. The genus is native to Eurasia but the two most commonplace species worldwide, T. officinale (the common dandelion) and T. erythrospermum (the red-seeded dandelion), were introduced from Europe into North America, where they are an invasive species. Dandelions thrive in temperate regions and can be found in yards, gardens, sides of roads, among crops, and in many other habitats. Both species are edible in their entirety and have a long history of consumption. The common name dandelion (/ˈdændəlaɪ.ən/DAN-də-ly-ən; from Frenchdent-de-lion 'lion's tooth', referring to the jagged leaves) is also given to specific members of the genus.
Like other members of the family Asteraceae, they have very small flowers collected together into a composite flower head. Each single flower in a head is called a floret. In part due to their abundance, along with being a generalist species, dandelions are one of the most vital early spring nectar sources for a wide host of pollinators. Many Taraxacum species produce seeds asexually by apomixis, where the seeds are produced without pollination, resulting in offspring that are genetically identical to the parent plant. (Full article...)
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Evolutionary developmental biology (evo-devo) is the study of developmental programs and patterns from an evolutionary perspective. It seeks to understand the various influences shaping the form and nature of life on the planet. Evo-devo arose as a separate branch of science rather recently. An early sign of this occurred in 1999.
Vegetative reproduction (also known as vegetative propagation, vegetative multiplication or cloning) is a form of asexual reproduction occurring in plants in which a new plant grows from a fragment or cutting of the parent plant or specialized reproductive structures, which are sometimes called vegetative propagules.
Many plants naturally reproduce this way, but it can also be induced artificially. Horticulturists have developed asexual propagation techniques that use vegetative propagules to replicate plants. Success rates and difficulty of propagation vary greatly. Monocotyledons typically lack a vascular cambium, making them more challenging to propagate. (Full article...)
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An heirloom plant, heirloom variety, heritage fruit (Australia and New Zealand), or heirloom vegetable (especially in Ireland and the UK) is an old cultivar of a plant used for food that is grown and maintained by gardeners and farmers, particularly in isolated communities of the Western world. These were commonly grown during earlier periods in human history, but are not used in modern large-scale agriculture.
In some parts of the world, it is illegal to sell seeds of cultivars that are not listed as approved for sale. The Henry Doubleday Research Association, now known as Garden Organic, responded to this legislation by setting up the Heritage Seed Library to preserve seeds of as many of the older cultivars as possible. However, seed banks alone have not been able to provide sufficient insurance against catastrophic loss. In some jurisdictions, like Colombia, laws have been proposed that would make seed saving itself illegal. (Full article...)
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Herbicides (US: /ˈɜːrbɪsaɪdz/, UK: /ˈhɜːr-/), also commonly known as weed killers, are substances used to control undesired plants, also known as weeds. Selective herbicides control specific weed species while leaving the desired crop relatively unharmed, while non-selective herbicides (sometimes called "total weed killers") kill plants indiscriminately. The combined effects of herbicides, nitrogen fertilizer, and improved cultivars has increased yields (per acre) of major crops by 3x to 6x from 1900 to 2000.
In the United States in 2012, about 91% of all herbicide usage, determined by weight applied, was in agriculture. In 2012, world pesticide expenditures totaled nearly $24.7 billion; herbicides were about 44% of those sales and constituted the biggest portion, followed by insecticides, fungicides, and fumigants. Herbicide is also used in forestry, where certain formulations have been found to suppress hardwood varieties in favor of conifers after clearcutting, as well as pasture systems. (Full article...)
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Various gymnosperms.
The gymnosperms (/ˈdʒɪmnəˌspɜːrmz,-noʊ-/ⓘJIM-nə-spurmz, -noh-; lit.'revealed seeds') are a group of seed-producing 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.
The gymnosperms and angiosperms together constitute the spermatophytes or seed plants. The spermatophytes are subdivided into five divisions, the angiosperms and four divisions of gymnosperms: the Cycadophyta, Ginkgophyta, Gnetophyta, and Pinophyta (also known as Coniferophyta). Newer classification place the gnetophytes among the conifers. Numerous extinct seed plant groups are recognised including those considered pteridosperms/seed ferns, as well other groups like the Bennettitales. (Full article...)
Plant milk is a non-dairy beverage made from a water-based plantextract for flavoring and aroma. Plant milks are consumed as alternatives to dairy milk, and may provide a creamy mouthfeel.
As of 2021, there are about 17 different types of plant milks; almond, oat, soy, coconut, and pea are the highest-selling worldwide. Production of plant-based milks, particularly soy, oat, and pea milks, can offer environmental advantages over animal milks in terms of greenhouse gas emissions, land and water use. (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...)
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Acer rubrum, the red maple, also known as swamp maple, water maple, or soft maple, is one of the most common and widespread deciduous trees of eastern and central North America. The U.S. Forest Service recognizes it as the most abundant native tree in eastern North America. The red maple ranges from southeastern Manitoba around the Lake of the Woods on the border with Ontario and Minnesota, east to Newfoundland, south to Florida, and southwest to East Texas. Many of its features, especially its leaves, are quite variable in form. At maturity, it often attains a height around 30 m (100 ft). Its flowers, petioles, twigs, and seeds are all red to varying degrees. Among these features, however, it is best known for its brilliant deep scarlet foliage in autumn.
Over most of its range, red maple is adaptable to a very wide range of site conditions, perhaps more so than any other tree in eastern North America. It can be found growing in swamps, on poor, dry soils, and almost anywhere in between. It grows well from sea level to about 900 m (3,000 ft). Due to its attractive fall foliage and pleasing form, it is often used as a shade tree for landscapes. It is used commercially on a small scale for maple syrup production and for its medium to high quality lumber. It is also the state tree of Rhode Island. The red maple can be considered weedy or even invasive in young, highly disturbed forests, especially frequently logged forests. In a mature or old-growth northern hardwood forest, red maple only has a sparse presence, while shade-tolerant trees such as sugar maples, beeches, and hemlocks thrive. By removing red maple from a young forest recovering from disturbance, the natural cycle of forest regeneration is altered, changing the diversity of the forest for centuries to come. (Full article...)
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Richard Buxton (15 January 1785 – 2 January 1865) was a British shoemaker and amateur botanist. Born in Prestwich, Lancashire, to a family who lived in humble circumstances, he taught himself to read, and learned the basic principles of botany. Although living as a pauper for most of his life, in 1849 he published A Botanical Guide to the Flowering Plants, Ferns, Mosses and Algæ, Found Indigenous Within Sixteen Miles of Manchester, which became one of the standard texts on the flora then commonly found in the Manchester area. According to his obituary in the Journal of Botany, British and Foreign, Buxton was one of "nature's gentlemen" and "his true and correct pronunciation of scientific terms have caused many who heard him to believe he was an accomplished classical scholar". He was acknowledged by the geologist Edward William Binney as "the most profound thinker of his class". (Full article...)
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White trillium blooming in Backus Woods (Ontario, Canada).
Trillium grandiflorum is most common in rich, mixed upland forests. It is easily recognised by its attractive three-petaled white flowers, opening from late spring to early summer, that rise above a whorl of three leaf-like bracts. It is an example of a spring ephemeral, a plant whose life-cycle is synchronised with that of the deciduous woodland which it favours. (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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Gray in the 1870s
Asa GrayForMemRS (November 18, 1810 – January 30, 1888) is considered the most important American botanist of the 19th century. His Darwiniana was considered an important explanation of how religion and science were not necessarily mutually exclusive. Gray was adamant that a genetic connection must exist between all members of a species. He was also strongly opposed to the ideas of hybridization within one generation and special creation in the sense of its not allowing for evolution. He was a strong supporter of Darwin, although Gray's theistic evolution was guided by a Creator.
As a professor of botany at Harvard University for several decades, Gray regularly visited, and corresponded with, many of the leading natural scientists of the era, including Charles Darwin, who held great regard for him. Gray made several trips to Europe to collaborate with leading European scientists of the era, as well as trips to the southern and western United States. He also built an extensive network of specimen collectors. (Full article...)
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 in tropical and subtropical areas 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...)
The taxonomy of the plant family Liliaceae has had a complex history since its first description in the mid-eighteenth century. Originally, the Liliaceae were defined as having a "calix" (perianth) of six equal-coloured parts, six stamens, a single style, and a superior, three-chambered (trilocular) ovary turning into a capsule fruit at maturity. The taxonomic circumscription of the family Liliaceae progressively expanded until it became the largest plant family and also extremely diverse, being somewhat arbitrarily defined as all species of plants with six tepals and a superior ovary. It eventually came to encompass about 300 genera and 4,500 species, and was thus a "catch-all" and hence paraphyletic. Only since the more modern taxonomic systems developed by the Angiosperm Phylogeny Group (APG) and based on phylogenetic principles, has it been possible to identify the many separate taxonomic groupings within the original family and redistribute them, leaving a relatively small core as the modern family Liliaceae, with fifteen genera and 600 species.
Charlotte was born into the ruling family of Mecklenburg-Strelitz, a duchy in northern Germany. In 1760, the young and unmarried George III inherited the British throne. As Charlotte was a minor German princess with no interest in politics, the King considered her a suitable consort, and they married in 1761. The marriage lasted 57 years and produced 15 children, 13 of whom survived to adulthood. They included two future British monarchs, George IV and William IV; as well as Charlotte, Princess Royal, who became Queen of Württemberg; and Prince Ernest Augustus, who became King of Hanover. (Full article...)
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A cultivar is a kind of cultivated plant that people have selected for desired traits and which retains those traits when propagated. Methods used to propagate cultivars include division, root and stem cuttings, offsets, grafting, tissue culture, or carefully controlled seed production. Most cultivars arise from deliberate human manipulation, but some originate from wild plants that have distinctive characteristics. Cultivar names are chosen according to rules of the International Code of Nomenclature for Cultivated Plants (ICNCP), and not all cultivated plants qualify as cultivars. Horticulturists generally believe the word cultivar was coined as a term meaning "cultivated variety".
Popular ornamental plants like roses, camellias, daffodils, rhododendrons, and azaleas are commonly cultivars produced by breeding and selection or as sports, for floral colour or size, plant form, or other desirable characteristics. Similarly, the world's agricultural food crops are almost exclusively cultivars that have been selected for characters such as improved yield, flavour, and resistance to disease, and very few wild plants are now used as food sources. Trees used in forestry are also special selections grown for their enhanced quality and yield of timber. (Full article...)
In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, including only woody plants with secondary growth, plants that are usable as lumber or plants above a specified height. In wider definitions, the taller palms, tree ferns, bananas, and bamboos are also trees.
Trees are not a monophyletic taxonomic group but consist of a wide variety of plant species that have independently evolved a trunk and branches as a way to tower above other plants to compete for sunlight. The majority of tree species are angiosperms or hardwoods; of the rest, many are gymnosperms or softwoods. Trees tend to be long-lived, some reaching several thousand years old. Trees evolved around 370 million years ago, and it is estimated that there are around three trillion mature trees in the world currently. (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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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
Historia Plantarum was written some time between c. 350 BC and c. 287 BC in ten volumes, of which nine survive. In the book, Theophrastus described plants by their uses, and attempted a biological classification based on how plants reproduced, a first in the history of botany. He continually revised the manuscript, and it remained in an unfinished state on his death. The condensed style of the text, with its many lists of examples, indicate that Theophrastus used the manuscript as the working notes for lectures to his students, rather than intending it to be read as a book. (Full article...)
... that the woodland garden, "colourfully planted with exotic shrubs and herbaceous plants, dominated English horticulture from 1910 to 1960"?
... 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 4The 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 5A 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 9The branching pattern of megaphyll veins may indicate their origin as webbed, dichotomising branches. (from Evolutionary history of plants)
Image 10The 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 11A botanist preparing a plant specimen for mounting in the herbarium (from Botany)
Image 12Echeveria glauca in a Connecticut greenhouse. Botany uses Latin names for identification; here, the specific name glauca means blue. (from Botany)
Image 14The 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 16The 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 17This is an electron micrograph of the epidermal cells of a Brassica chinensis leaf. The stomates are also visible. (from Plant cell)
Image 18Structure 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 19Transverse section of a fossil stem of the Devonian vascular plant Rhynia gwynne-vaughani (from Botany)
Image 20Thale cress, Arabidopsis thaliana, the first plant to have its genome sequenced, remains the most important model organism. (from Botany)
Image 21Structure of a plant cell (from Plant cell)
Image 221 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 24A nineteenth-century illustration showing the morphology of the roots, stems, leaves and flowers of the rice plant Oryza sativa (from Botany)
Image 25Five of the key areas of study within plant physiology (from Botany)
Image 26A 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)