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...)
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Banksia ilicifolia, commonly known as holly-leaved banksia, is a tree in the familyProteaceae. Endemic to southwest Western Australia, it belongs to Banksia subg. Isostylis, a subgenus of three closely related Banksia species with inflorescences that are dome-shaped heads rather than characteristic Banksia flower spikes. It is generally a tree up to 10 metres (33 ft) tall with a columnar or irregular habit. Both the scientific and common names arise from the similarity of its foliage to that of the English holly Ilex aquifolium; the glossy green leaves generally have very prickly serrated margins, although some plants lack toothed leaves. The inflorescences are initially yellow but become red-tinged with maturity; this acts as a signal to alert birds that the flowers have opened and nectar is available.
Robert Brown described Banksia ilicifolia in 1810. Although Banksia ilicifolia is variable in growth form, with low coastal shrubby forms on the south coast near Albany, there are no recognised varieties as such. Distributed broadly, the species is restricted to sandy soils. Unlike its close relatives which are killed by fire and repopulate from seed, Banksia ilicifolia regenerates after bushfire by regrowing from epicormic buds under its bark. It is rarely cultivated. (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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Persoonia levis, commonly known as the broad-leaved geebung, is a shrub native to New South Wales and Victoria in eastern Australia. It reaches 5 m (16 ft) in height and has dark grey papery bark and bright green asymmetrical sickle-shaped leaves up to 14 cm (5.5 in) long and 8 cm (3.2 in) wide. The small yellow flowers appear in summer and autumn (December to April), followed by small green fleshy fruit, which are classified as drupes. Within the genus Persoonia, it is a member of the Lanceolata group of 58 closely related species. P. levis interbreeds with several other species where they grow together.
Barbara McClintock (June 16, 1902 – September 2, 1992) was an American scientist and cytogeneticist who was awarded the 1983 Nobel Prize in Physiology or Medicine. McClintock received her PhD in botany from Cornell University in 1927. There she started her career as the leader of the development of maize cytogenetics, the focus of her research for the rest of her life. From the late 1920s, McClintock studied chromosomes and how they change during reproduction in maize. She developed the technique for visualizing maize chromosomes and used microscopic analysis to demonstrate many fundamental genetic ideas. One of those ideas was the notion of genetic recombination by crossing-over during meiosis—a mechanism by which chromosomes exchange information. She is often erroneously credited with producing the first genetic map for maize, linking regions of the chromosome to physical traits. She demonstrated the role of the telomere and centromere, regions of the chromosome that are important in the conservation of genetic information. She was recognized as among the best in the field, awarded prestigious fellowships, and elected a member of the National Academy of Sciences in 1944.
During the 1940s and 1950s, McClintock discovered transposons and used it to demonstrate that genes are responsible for turning physical characteristics on and off. She developed theories to explain the suppression and expression of genetic information from one generation of maize plants to the next. Due to skepticism of her research and its implications, she stopped publishing her data in 1953. (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...)
Banksia sphaerocarpa, commonly known as the fox banksia or round-fruit banksia, is a species of shrub or tree in the plant genus Banksia (family Proteaceae). It is generally encountered as a 1–2 m (3.3–6.6 ft) high shrub, and is usually smaller in the north of its range. This species has narrow green leaves, and brownish, orange or yellow round flower spikes which may be seen from January to July. It is widely distributed across the southwest of Western Australia, growing exclusively in sandy soils. It is usually the dominant plant in scrubland or low woodland. It is pollinated by, and is a food source for, birds, mammals, and insects.
First described in 1810 by botanist Robert Brown, B. sphaerocarpa has a complicated taxonomic history, and several taxa once classified as part of a broadly defined B. sphaerocarpa have since been named as species in their own right. At present, most authorities recognise five varieties; the largest variety, B. sphaerocarpa var. dolichostyla (ironcap banksia), is sometimes given species rank as B. dolichostyla. B. sphaerocarpa is classified as Not Threatened under the Wildlife Conservation Act of Western Australia, although two varieties have been placed on the Declared Rare and Priority Flora List—var. latifolia has been designated a Priority Two – Poorly Known taxon, and var. dolichostyla falls under Declared Rare Flora. None of the varieties are commonly seen in cultivation. (Full article...)
Ficus macrophylla, commonly known as the Moreton Bay fig or Australian banyan, is a large evergreen banyan tree of the mulberry and fig family Moraceae. It is native to eastern Australia, from the Wide Bay–Burnett region of Queensland in the north to the Illawarra region of New South Wales. The infraspeciesFicus macrophylla f. columnaris is endemic to Lord Howe Island. Its common name refers to Moreton Bay in Queensland. It is best known for its imposing buttress roots.
Ficus macrophylla is called a strangler fig because seed germination usually takes place in the canopy of a host tree, where the seedling lives as an epiphyte until its roots establish contact with the ground, when it enlarges and strangles its host, eventually becoming a freestanding tree by itself. Individuals may reach 60 m (200 ft) in height. The greatest exact height to be reported is 70.6 m (232 ft). It has an obligate mutualism with fig wasps; figs are pollinated only by fig wasps, and fig wasps can reproduce only in fig flowers. The wasp partner of the Moreton Bay Fig is Pleistodontes froggattii. Many species of birds, including pigeons, parrots, and various passerines, eat the fruit. (Full article...)
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Brachychiton rupestris (commonly known as the narrow-leaved bottle tree or Queensland bottle tree) is a tree in the familyMalvaceae, endemic to the Australian state of Queensland. Described by Sir Thomas Mitchell and John Lindley in 1848, it earned its name from its bulbous trunk, which can be up to 3.5 metres (11 ft) in diameter at breast height (DBH). Reaching around 10–25 m (33–82 ft) high, the Queensland bottle tree is deciduous, losing its leaves seasonally, between September and December. The leaves are simple or divided, with one or more narrow leaf blades up to 11 centimetres (4 in) long and 2 cm (0.8 in) wide. Cream-coloured flowers appear from September to November, and are followed by woody, boat-shaped follicles that ripen from November to May. No subspecies are recognised.
As a drought deciduoussucculent tree, much like the baobab (Adansonia) of Madagascar, B. rupestris adapts readily to cultivation, and is quite tolerant of a range of soils and temperatures. It is a key component and emergent tree in the endangered central semi-evergreen vine thickets (also known as bottletree scrub) of the Queensland Brigalow Belt. Remnant trees are often left by farmers on cleared land for their value as shade and fodder trees, and as homes for various birds and animals. (Full article...)
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Adenanthos cuneatus, also known as coastal jugflower, flame bush, bridle bush and sweat bush, is a shrub of the family Proteaceae, native to the south coast of Western Australia. The French naturalist Jacques Labillardière originally described it in 1805. Within the genus Adenanthos, it lies in the sectionAdenanthos and is most closely related to A. stictus. A. cuneatus has hybridized with four other species of Adenanthos. Growing to 2 m (6 ft 7 in) high and wide, it is erect to prostrate in habit, with wedge-shaped lobed leaves covered in fine silvery hair. The single red flowers are insignificant, and appear all year, though especially in late spring. The reddish new growth occurs over the summer.
It is sensitive to Phytophthora cinnamomidieback, hence requiring a sandy soil and good drainage to grow in cultivation, its natural habitat of sandy soils in heathland being an example. Its pollinators include bees, honey possum, silvereye and honeyeaters, particularly the western spinebill. A. cuneatus is grown in gardens in Australia and the western United States, and dwarf and prostrate forms are commercially available. (Full article...)
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Lambertia formosa, commonly known as mountain devil, is a shrub of the family Proteaceae, endemic to New South Wales, Australia. First described in 1798 by English botanist James Edward Smith, it is the type species of the small genus Lambertia. It is generally found in heathland or open forest, growing in sandstone-based soils. It grows as a multistemmed shrub to around 2 m (7 ft) with a woody base known as a lignotuber, from which it regrows after bushfire. It has stiff narrow leaves, and the pink to red flowerheads, made up of seven individual tubular flowers, generally appear in spring and summer. It gains its common name from the horned woody follicles, which were used to make small devil-figures.
The flowers hold profuse amounts of nectar and are pollinated by honeyeaters. Although L. formosa is uncommon in cultivation, it is straightforward to grow in soils with good drainage and a partly shaded to sunny aspect. It is readily propagated by seed. Unlike all other members of the genus Lambertia, L. formosa is greatly resistant to the soil pathogen Phytophthora cinnamomi. (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...)
Two subspecies—P.t.terminalis and P.t.recurva—are recognised; both are found on well-drained acidic soils in sclerophyll forests, and P.t.terminalis is also found on granite outcrops. Although similar in appearance, they differ in leaf length and curvature. Both have a restricted range, with P.t.terminalis found in an area of under 100 square kilometres (39 square miles; 25,000 acres). (Full article...)
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Banksia caleyi, commonly known as Caley's banksia or red lantern banksia, is a species of woody shrub of the family Proteaceae native to Western Australia. It generally grows as a dense shrub up to 2 m (7 ft) tall, has serrated leaves and red, pendent (hanging) inflorescences which are generally hidden in the foliage. First described by Scottish naturalist Robert Brown in 1830, Banksia caleyi was named in honour of the English botanist George Caley. No subspecies are recognised. It is one of three or four related species with hanging inflorescences, which is an unusual feature within the genus.
Metrosideros bartlettii, commonly known as Bartlett's rātā, is a rare species of tree in the family Myrtaceae. It is endemic to the Northland Region in New Zealand's North Island. Bartlett's rātā reaches a height of up to 30 metres (100 feet) with a trunk of 1–1.5 metres (3 ft 3 in – 4 ft 11 in) in diameter. The species is classified in the subgenusMetrosideros and is known for its distinct whitish, paper-like bark and small white-coloured flowers. Bartlett's rātā was first discovered in 1975 by the New Zealand botanist and schoolteacher John Bartlett, who accidentally discovered the species while searching for liverworts near Cape Reinga. It was first described by botanist John Dawson in a 1985 article in the New Zealand Journal of Botany.
Bartlett's rātā's range covers the northern tip of the Aupōuri Peninsula, in three dense forest remnants near Piwhane / Spirits Bay. Bartlett's rātā typically begins life as an epiphyte (growing on another plant); it inhabits lowland forests and is usually found growing near wet areas. A 2018 article by the New Zealand Plant Conservation Network documented 13 adult trees in the wild, a significant decrease from another research article in 2000 that documented 31 wild adult trees. The species has a high chance of becoming extinct in the wild unless immediate conservation measures are taken to stop its ongoing decline, which has been attributed to land use changes following human settlement and the introduction of common brushtail possums, which browse its buds, flowers, and shoots. Bartlett's rātā's conservation status was assessed by the IUCN Red List in 2013 as critically endangered, and its population trend was assessed as decreasing. (Full article...)
Banksia menziesii, commonly known as firewood banksia, is a species of flowering plant in the family Proteaceae. It is a gnarled tree up to 10 m (33 ft) tall, or a lower spreading 1–3 m (3.3–9.8 ft) shrub in the more northern parts of its range. The serrated leaves are dull green with new growth a paler grey green. The prominent autumn and winter inflorescences are often two-coloured red or pink and yellow, and their colour has given rise to more unusual common names such as port wine banksia and strawberry banksia. Yellow blooms are rarely seen.
First described by the botanist Robert Brown in the early 19th century, no separate varieties of Banksia menziesii are recognised. It is found in Western Australia, from the Perth (32° S) region north to the Murchison River (27° S), and generally grows on sandy soils, in scrubland or low woodland. Banksia menziesii provides food for a wide array of invertebrate and vertebrate animals; birds and in particular honeyeaters are prominent visitors. A relatively hardy plant, Banksia menziesii is commonly seen in gardens, nature strips and parks in Australian urban areas with Mediterranean climates, but its sensitivity to dieback from the soil-borne water mould Phytophthora cinnamomi makes it short-lived in places with humid summers, such as Sydney. Banksia menziesii is widely used in the cut flower industry both in Australia and overseas. (Full article...)
White tea, yellow tea, green tea, oolong, dark tea (which includes pu-erh tea) and black tea are all made from two of the five varieties which form the main crops now grown, 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 made from C. sinensis, but uses twigs and stems rather than leaves. (Full article...)
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Edith Gertrude Clements (1874–1971), also known as Edith S. Clements and Edith Schwartz Clements, was an American botanist and pioneer of botanical ecology who was the first woman to be awarded a Ph.D. by the University of Nebraska. She was married to botanist Frederic Clements, with whom she collaborated throughout her professional life. Together they founded the Alpine Laboratory, a research station at Pikes Peak, Colorado. Clements was also a botanical artist who illustrated her own books as well as joint publications with Frederic.
Both Clementses were involved with the study of phytogeography, especially those factors determining the ecology of vegetation in particular regions, and they would be praised as "the most illustrious husband-wife team since the Curies." It is impossible to entirely disentangle the work of each Clementses as they worked together during their noteworthy years. (Full article...)
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Ethnobotanist Richard Evans Schultes at work in the Amazon in the 1940s Ethnobotany is an interdisciplinary field at the interface of natural and social sciences that studies the relationships between humans and plants. It focuses on traditional knowledge of how plants are used, managed, and perceived in human societies. Ethnobotany integrates knowledge from botany, anthropology, ecology, and chemistry to study plant-related customs across cultures. Researchers in this field document and analyze how different societies use local flora for various purposes, including medicine, food, religious use, intoxicants, building materials, fuels and clothing. Richard Evans Schultes, often referred to as the "father of ethnobotany", provided an early definition of the discipline:Since Schultes' time, ethnobotany has evolved from primarily documenting traditional plant knowledge to applying this information in modern contexts, particularly in pharmaceutical development. The field now addresses complex issues such as intellectual property rights and equitable benefit-sharing arrangements arising from the use of traditional knowledge. (Full article...)
The embryophytes are informally called "land plants" because they thrive primarily in terrestrial habitats (despite some members having evolved secondarily to live once again in semiaquatic/aquatic habitats), while the related green algae are primarily aquatic. Embryophytes are complex multicellulareukaryotes with specialized reproductive organs. The name derives from their innovative characteristic of nurturing the young embryo sporophyte during the early stages of its multicellular development within the tissues of the parent gametophyte. With very few exceptions, embryophytes obtain biological energy by photosynthesis, using chlorophyll a and b to harvest the light energy in sunlight for carbon fixation from carbon dioxide and water in order to synthesize carbohydrates while releasing oxygen as a byproduct. The study of land plants is called phytology. (Full article...)
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Ethylene chemical structure. Ethylene signaling pathway is a signal transduction in plant cells to regulate important growth and developmental processes. Acting as a plant hormone, the gas ethylene is responsible for promoting the germination of seeds, ripening of fruits, the opening of flowers, the abscission (or shedding) of leaves and stress responses. It is the simplest alkene gas and the first gaseous molecule discovered to function as a hormone.
Most of the understanding on ethylene signal transduction come from studies on Arabidopsis thaliana. Ethylene can bind to at least five different membrane gasoreceptors. Although structurally diverse, the ethylene gasoreceptors all exhibit similarity (homology) to two-component regulatory system in bacteria, indicating their common ancestry from bacterial ancestor. Ethylene binds to the gasoreceptors on the cell membrane of the endoplasmic reticulum. Although homodimers of the gasoreceptors are required for functional state, only one ethylene molecule binds to each dimer. (Full article...)
Originating in South America, Solanaceae now inhabit every continent on Earth except Antarctica. After the K–Pg extinction event they rapidly diversified and have adapted to live in deserts, tundras, rainforests, plains, and highlands, and taken on wide range of forms including trees, vines, shrubs, and epiphytes. Nearly 80% of all nightshades are included in the subfamily Solanoideae, most of which are members of the type genus Solanum. Most taxonomists recognize six other subfamilies: Cestroideae, Goetzeoideae, Nicotianoideae, Petunioideae, Schizanthoideae, and Schwenkioideae, although nightshade taxonomy is still controversial. The genus Duckeodendron is sometimes placed in its own subfamily, Duckeodendroideae. (Full article...)
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Carl Linnaeus's garden at Uppsala, Sweden The International Code of Nomenclature for algae, fungi, and plants (ICN or ICNafp) is the set of rules and recommendations dealing with the formal botanical names that are given to plants, fungi and a few other groups of organisms, all those "traditionally treated as algae, fungi, or plants". It was formerly called the International Code of Botanical Nomenclature (ICBN); the name was changed at the International Botanical Congress in Melbourne in July 2011 as part of the Melbourne Code which replaced the Vienna Code of 2005.
The ICN can only be changed by an International Botanical Congress (IBC), with the International Association for Plant Taxonomy providing the supporting infrastructure. Each new edition supersedes the earlier editions and is retroactive back to 1753, except where different starting dates are specified. (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...)
Some species are shrubs, trees (such as teak), or, rarely, vines. Many members of the family are widely cultivated, not only for their aromatic qualities, but also their ease of cultivation, since they are readily propagated by stem cuttings. Besides those grown for their edible leaves, some are grown for decorative foliage. Others are grown for seed, such as Salvia hispanica (chia), or for their edible tubers, such as Plectranthus edulis, P. esculentus, P. rotundifolius, and Stachys affinis (Chinese artichoke). Many are also grown ornamentally, notably coleus, Plectranthus, and many Salvia species and hybrids. (Full article...)
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In phytogeography, a phytochorion is a geographic area with a relatively uniform composition of plant species. Adjacent phytochoria do not usually have a sharp boundary, but rather a soft one, a transitional area in which many species from both regions overlap, called a vegetation tension zone.
In traditional schemes, areas in phytogeography are classified hierarchically, according to the presence of endemic families, genera or species, e.g., in floral (or floristic, phytogeographic) zones and regions, or also in kingdoms, regions and provinces, sometimes including the categories empire and domain. However, some authors prefer not to rank areas, referring to them simply as "areas", "regions" (in a non hierarchical sense) or "phytochoria". (Full article...)
The arrival of humans around 50,000 years ago and the settlement by Europeans from 1788, has had a significant impact on the flora. The use of fire-stick farming by Aboriginal people led to significant changes in the distribution of plant species over time, and the large-scale modification or destruction of vegetation for agriculture and urban development since 1788 has altered the composition of most terrestrial ecosystems, leading to the extinction of 61 plant species by 2006, and endangering over 1000 more. (Full article...)
An arboretum (pl.: arboreta) is a botanical collection composed exclusively of trees and shrubs of a variety of species. Originally mostly created as a section in a larger garden or park for specimens of mostly non-local species, many modern arboreta are in botanical gardens as living collections of woody plants and are intended at least in part for scientific study.
In Latin, an arboretum is a place planted with trees, not necessarily in this specific sense, and "arboretum" as an English word is first recorded used by John Claudius Loudon in 1833 in The Gardener's Magazine, but the concept was already long-established by then. (Full article...)
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Cornus kousa var. chinensis
Cornus is a genus of about 30–60 species of woody plants in the familyCornaceae, commonly known as dogwoods or cornels, which can generally be distinguished by their blossoms, berries, and distinctive bark. Most are deciduoustrees or shrubs, but a few species are nearly herbaceous perennial subshrubs, and some species are evergreen. Several species have small heads of inconspicuous flowers surrounded by an involucre of large, typically white petal-like bracts, while others have more open clusters of petal-bearing flowers. The various species of dogwood are native throughout much of temperate and boreal Eurasia and North America, with China, Japan, and the southeastern United States being particularly rich in native species. The genus is also known from South America with members such as Cornus peruviana.
Species include the common dogwood Cornus sanguinea of Eurasia, the widely cultivated flowering dogwood (Cornus florida) of eastern North America, the Pacific dogwood Cornus nuttallii of western North America, the Kousa dogwood Cornus kousa of eastern Asia, and two low-growing boreal species, the Canadian and Eurasian dwarf cornels (or bunchberries), Cornus canadensis and Cornus suecica respectively. (Full article...)
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Rafflesia keithii flower
The Rafflesiaceae are a family of rare parasiticplants comprising 36 species in 3 genera found in the tropical forests of east and southeast Asia, including Rafflesia arnoldii, which has the largest flowers of all plants. The plants are endoparasites of vines in the genus Tetrastigma (Vitaceae) and lack stems, leaves, roots, and any photosynthetic tissue. They rely entirely on their host plants for both water and nutrients, and only then emerge as flowers from the roots or lower stems of the host plants. (Full article...)
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Australia, 1907: Cattlemen survey 700 cattle that were killed overnight by poisonous plants
Plants that cause illness or death after consuming them are referred to as poisonous plants. The toxins in poisonous plants affect herbivores, and deter them from consuming the plants. Plants cannot move to escape their predators, so they must have other means of protecting themselves from herbivorous animals. Some plants have physical defenses such as thorns, spines and prickles, but by far the most common type of protection is chemical.
Over millennia, through the process of natural selection, plants have evolved the means to produce a vast and complicated array of chemical compounds to deter herbivores. Tannin, for example, is a defensive compound that emerged relatively early in the evolutionary history of plants, while more complex molecules such as polyacetylenes are found in younger groups of plants such as the Asterales. Many of the known plant defense compounds primarily defend against consumption by insects, though other animals, including humans, that consume such plants may also experience negative effects, ranging from mild discomfort to death. (Full article...)
It is estimated that there are about 9000 species of liverwort. Some of the more familiar species grow as a flattened leafless thallus, but most species are leafy with a form very much like a flattened moss. Leafy species can be distinguished from the apparently similar mosses on the basis of a number of features, including their single-celled rhizoids. Leafy liverworts also differ from most (but not all) mosses in that their leaves never have a costa (present in many mosses) and may bear marginal cilia (very rare in mosses). Other differences are not universal for all mosses and liverworts, but the occurrence of leaves arranged in three ranks, the presence of deep lobes or segmented leaves, or a lack of clearly differentiated stem and leaves all point to the plant being a liverwort. Liverworts are distinguished from mosses in having unique complex oil bodies of high refractive index. (Full article...)
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Hypericum foliosum, the shining St John's wort, is a species of flowering plant in the family Hypericaceae. It is a bushy shrub endemic to the Portuguese Azores Islands with golden yellow petals and many stems. The species was described by William Aiton in 1789 and was later placed into section Androsaemum of the genus Hypericum by Norman Robson in 1984. It has a diverse essential oil profile made up mostly of monoterpene hydrocarbons, and significant concentrations of various medicinally useful phenols and carotenoids. Populations of the plant are small in number, but quick to colonize cleared areas like groves, landslide areas, and volcanic ash deposits. It is parasitized by fungus and by moth species, but is not considered endangered by the IUCN. H. foliosum is used in traditional medicine on the Azores for diuretic, hepatoprotective, and antihypertensive purposes. It also has in vitroantibiotic and antioxidizing capabilities. (Full article...)
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Cylindropuntia imbricata, the cane cholla (walking stick cholla, tree cholla, or chainlink cactus), is a cactus found in the Southwestern United States and northern Mexico, including some cooler regions in comparison to many other cacti. It occurs primarily in the arid regions of the Southwestern United States in the states of Kansas, Oklahoma, Texas, New Mexico, Arizona, Colorado, and Nevada. It is often conspicuous because of its shrubby or even tree-like size, its silhouette, and its long-lasting yellowish fruits. (Full article...)
Stylidium (the triggerplants or trigger plants) is a genus of dicotyledonousplants that belong to the family Stylidiaceae. The genus name Stylidium is derived from the Greek στύλος or stylos (column or pillar), which refers to the distinctive reproductive structure that its flowers possess. Pollination is achieved through the use of the sensitive "trigger", which comprises the male and female reproductive organs fused into a floral column that snaps forward quickly in response to touch, harmlessly covering the insect in pollen. Most of the approximately 300 species are only found in Australia, making it the fifth largest genus in that country. Triggerplants are considered to be protocarnivorous or carnivorous because the glandular trichomes that cover the scape and flower can trap, kill, and digest small insects with protease enzymes produced by the plant. Recent research has raised questions as to the status of protocarnivory within Stylidium. (Full article...)
Pouyannian mimicry is a form of mimicry in plants that deceives an insect into attempting to copulate with a flower. The flower mimics a potential female mate of a male insect, which then serves the plant as a pollinator. The mechanism is named after the French lawyer and amateur botanist Maurice-Alexandre Pouyanne. The resemblance that he noted is visual, but the key stimuli that deceive the pollinator are often chemical and tactile.
In orchids, the resemblance is to a species of bee; Pouyanne observed the bee Dasyscolia ciliata pollinating the orchid Ophrys speculum. The flower uses morphology, coloration, and scent to deceive the pollinator. The chemicals secreted from the flower's osmophore glands are indistinguishable from the insect's pheromones. The pollinator is not rewarded with nectar, and may waste significant amounts of sperm while trying to mate with the flower. (Full article...)
Hippeastrum (/ˌhɪpiːˈæstrəm/) is a genus of 116 species, and over 600 hybrids and cultivars, of perennial, herbaceous and bulbous plants, native to tropical and subtropical regions of the Americas, from Mexico south to Argentina and on some islands in the Caribbean. The majority have large, fleshy bulbs and tall, broad, strap-like leaves that are (generally) evergreen, and large red or purple flowers. Numerous colors and cultivars have been created over the past hundred years.
Hippeastrum is a genus in the familyAmaryllidaceae (subfamilyAmaryllidoideae, tribeHippeastreae, and subtribeHippeastrinae). For many years, there has been confusion among botanists, as well as collectors and the general public, over the generic names Amaryllis and Hippeastrum; the former is a South African genus of plants, while the latter is a new world genus. However, the common name "amaryllis" has been used for Hippeastrum for years, especially for the ornamental cultivars (sold as indoor flowering bulbs around November and December, for Christmas, in the Northern Hemisphere). Within the genus Hippeastrum exist many epiphytic species, as well, which may be found living in natural debris and leaf litter on the crooks of tree branches; by comparison, Amaryllis is a primarily terrestrial, southern African genus of perennial bulbs. (Full article...)
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Hyacinthoides non-scripta/ˌhaɪəsɪnˈθɔɪdiːznɒnˈskrɪptə/ (formerly Endymion non-scriptus or Scilla non-scripta) is a bulbousperennial plant found in Atlantic areas from the north-western part of the Iberian Peninsula to the British Isles, and also frequently used as a garden plant. It is known in English as the common bluebell or simply bluebell, a name which is used in Scotland to refer to the harebell, Campanula rotundifolia. In spring, H. non-scripta produces a nodding, one-sided inflorescence of 5–12 tubular, sweet-scented violet–blue flowers, with strongly recurved tepals, and 3–6 long, linear, basal leaves.
H. non-scripta is particularly associated with ancient woodland where it may dominate the understorey to produce carpets of violet–blue flowers in "bluebell woods", but also occurs in more open habitats in western regions. It is protected under UK law, and in some other parts of its range. A related species, H. hispanica has also been introduced to Britain and Ireland and hybridises with H. non-scripta to produce intermediates known as H. × massartiana. (Full article...)
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Hypericum × inodorum 'Golden Beacon' in Belgium
Hypericum × inodorum, called tall tutsan or the tall St John's wort, is a bushy perennialshrub with yellow flowers native to Western Europe. It has been known since 1789, but confusion around its name, identity, and origin persisted throughout the 19th and 20th centuries.
The coconut (Cocos nucifera) is a member of the palm family (Arecaceae) and the only living species of the genusCocos. The term "coconut" (or the archaic "cocoanut") can denote the whole coconut palmtree or the large hard fruit. Originally native to Central Indo-Pacific, they are ubiquitous in coastal tropical regions.
The coconut tree provides food, fuel, cosmetics, folk medicine and building materials. The inner flesh of the mature fruit forms a regular part of the diets of many people in the tropics and subtropics. Coconut endosperm contains a large quantity of a liquid, "coconut water". Mature coconuts can be processed for oil and coconut milk from the flesh, charcoal from the hard shell, and coir from the fibrous husk. Dried coconut flesh is called copra, and the oil and milk derived from it are commonly used in cooking and in soaps and cosmetics. Sweet coconut sap can be made into drinks or fermented into palm wine or coconut vinegar. The hard shells, fibrous husks and long pinnate leaves are used to make a products for furnishing and decoration. (Full article...)
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Foxgloves produce toxic chemicals such as digoxin in order to deter herbivory.
Plant defense against herbivory or host-plant resistance is a range of adaptationsevolved by plants which improve their survival and reproduction by reducing the impact of herbivores. Many plants produce secondary metabolites, known as allelochemicals, that influence the behavior, growth, or survival of herbivores. These chemical defenses can act as repellents or toxins to herbivores or reduce plant digestibility. Another defensive strategy of plants is changing their attractiveness. Plants can sense being touched, and they can respond with strategies to defend against herbivores. Plants alter their appearance by changing their size or quality in a way that prevents overconsumption by large herbivores, reducing the rate at which they are consumed.
Other defensive strategies used by plants include escaping or avoiding herbivores at any time in any place – for example, by growing in a location where plants are not easily found or accessed by herbivores or by changing seasonal growth patterns. Another approach diverts herbivores toward eating non-essential parts or enhances the ability of a plant to recover from the damage caused by herbivory. Some plants support the presence of natural enemies of herbivores, which protect the plant. Each type of defense can be either constitutive (always present in the plant) or induced (produced in reaction to damage or stress caused by herbivores). (Full article...)
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Portrait of Elfving, 1870s
Fredrik Emil Volmar Elfving (9 December 1854 – 21 June 1942) was a Swedish-speaking Finnish botanist, plant physiologist, and university administrator. During his university training, he frequently traveled abroad to learn new scientific methods and techniques from other prominent European scientists. Although his earliest publications dealt with phytogeography and phycology (particularly the green algae known as the desmids), his most notable research was in plant physiology. Early in his career, he published seminal work on the flow of water through the stems of woody plants, and investigated the phenomenon of transversely geotropic plant organs. In contrast to his works on plant physiology, his later experiments and views on lichens, which he himself considered his most important work, was far less favourably received.
Elfving became a Professor of botany at the University of Helsinki in 1892, a position he held until his retirement in 1926. A lively and enthusiastic teacher, Elfving revolutionized the teaching of botany at the university by introducing laboratory courses that emphasized the study of plant physiology, rather than taxonomy, as had been the tradition. During his time as professor, Elfving wrote many historical papers about scientific societies, and biographies of Scandinavian scientists. He wrote the books Tärkeimmät viljelyskasvit ("The Most Important Crops") and the Kasvitieteen oppikirja ("Botanical Textbook"), which were widely used as textbooks. Elfving has had several taxa named after him. (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...)
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Commelina communis flowers
Commelina communis the Asiatic dayflower, is an herbaceousannual plant in the dayflower family. It gets its name because the blooms last for only one day. It is native throughout much of East Asia and northern parts of Southeast Asia. In China, the plant is known as yazhicao (simplified Chinese: 鸭跖草; traditional Chinese: 鴨跖草; pinyin: yāzhīcǎo), roughly translating to "duckfoot herb", while in Japan it is known as tsuyukusa (露草, tsuyukusa), meaning "dew herb". It has also been introduced to parts of central and southeastern Europe and much of eastern North America, where it has spread to become a noxious weed. It is common in disturbed sites and in moist soil. The flowers emerge from summer through fall and are distinctive with two relatively large blue petals and one very small white petal.
The Asiatic dayflower plant serves as the type species for its large genus. Linnaeus picked the name Commelina in honour of the two Dutch botanists of the Commelijn family, using the two large showy petals of Commelina communis to symbolise them. Linnaeus described the species in the first edition of his landmark work, Species Plantarum, in 1753. Long before the plant was studied in Europe, however, it had been used for generations in traditional Chinese medicine. The flowers have also been used in Japan to produce a dye and a pigment that was used in many world-renowned Ukiyo-ewoodcuts from the 18th and early 19th centuries. In the modern era the plant has found limited use as a model organism in the field of plant physiology due to its complex pigment chemistry and the ease of viewing its stomata. (Full article...)
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Dogs and sheep were among the first animals to be domesticated, at least 15,000 and 11,000 years ago respectively. Domestication is a multi-generational mutualistic relationship in which an animal species, such as humans or leafcutter ants, takes over control and care of another species, such as sheep or fungi, to obtain from them a steady supply of resources, such as meat, milk, or labor. The process is gradual and geographically diffuse, based on trial and error. Domestication affected genes for behavior in animals, making them less aggressive. In plants, domestication affected genes for morphology, such as increasing seed size and stopping the shattering of cereal seedheads. Such changes both make domesticated organisms easier to handle and reduce their ability to survive in the wild.
... that according to Lois N. Magner, Hildegard of Bingen's Physica is "probably the first book by a female author to discuss the elements and the therapeutic virtues of plants, animals, and metals"?
... 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?
... that Marie Catharine Neal, an expert on Hawaiian plants, authored the acclaimed book In Gardens of Hawaii in 1948, which described more than 2,000 species with detailed scientific information and illustrations?
Image 4The 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 5The food we eat comes directly or indirectly from plants such as rice. (from Botany)
Image 10Structure 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 15A 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 16Paper chromatography of some spinach leaf extract shows the various pigments present in their chloroplasts: yellowish xanthophylls, greenish chlorophylls a and b. (from Botany)
Image 18Echeveria glauca in a Connecticut greenhouse. Botany uses Latin names for identification; here, the specific name glauca means blue. (from Botany)
Image 19A nineteenth-century illustration showing the morphology of the roots, stems, leaves and flowers of the rice plant Oryza sativa (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 21Structure of a plant cell (from Plant cell)
Image 22Micropropagation of transgenic plants (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 24Leaf lamina. The megaphyllous leaf architecture arose multiple times in different plant lineages (from Evolutionary history of plants)
Image 261 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 34The 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 35The Linnaean Garden of Linnaeus' residence in Uppsala, Sweden, was planted according to his Systema sexuale. (from Botany)
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