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...)
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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Margaret Sibella Brown (March 2, 1866 – November 16, 1961) was a Canadian amateur bryologist specializing in mosses and liverworts native to Nova Scotia. Early in her career she was involved with gathering supplies of sphagnum moss to be used as surgical dressings during World War I, when cotton was in short supply. After the war, she researched mosses from around the world, collecting specimens in Europe, the Caribbean, and the United States, as well as her native Canada. She published several papers in academic journals, some on materials she had collected herself and some cataloging samples collected by other investigators. Samples she collected are now housed at several major herbaria in North America and Europe.
Born into upper-class society, Brown was educated in Halifax, Stuttgart, and London. Although lacking formal scientific training, she has been recognized for her contributions to bryology and as an authority on the mosses and liverworts of Nova Scotia. At the age of 84, Brown was awarded an honorary M.A. degree from Acadia University after declining their offer of a Ph.D. She died at her home in Halifax in 1961 aged 95. In 2010, she was inducted into the Nova Scotia Scientific Hall of Fame. (Full article...)
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Telopea oreades, commonly known as the Gippsland-, mountain- or Victorian waratah, is a large shrub or small tree in the family Proteaceae. Native to southeastern Australia, it is found in wet sclerophyll forest and rainforest on rich acidic soils high in organic matter. No subspecies are recognised, though a northern isolated population hybridises extensively with the Braidwood waratah (T. mongaensis). Reaching a height of up to 19 metres (62 feet), T. oreades grows with a single trunk and erect habit. It has dark green leaves with prominent veins that are 11–28 centimetres (4.3–11 in) long and 1.5–6 cm (0.6–2.4 in) wide. The red flower heads, known as inflorescences, appear in late spring. Each is composed of up to 60 individual flowers.
In the garden, T. oreades grows in soils with good drainage and ample moisture in part-shaded or sunny positions. Several commercially available cultivars that are hybrid forms with T. speciosissima have been developed, such as the 'Shady Lady' series. The timber is hard and has been used for making furniture and tool handles. (Full article...)
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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 scabrella, commonly known as the Burma Road banksia, is a species of woody shrub in the genus Banksia. It is classified in the series Abietinae, a group of several species of shrubs with small round or oval inflorescences. It occurs in a number of isolated populations south of Geraldton, Western Australia, with the largest population being south and east of Mount Adams. Found on sandy soils in heathland or shrubland, it grows to 2 m (7 ft) high and 3 m (10 ft) across with fine needle-like leaves. Appearing in spring and summer, the inflorescences are round to oval in shape and tan to cream with purple styles. Banksia scabrella is killed by fire and regenerates by seed.
Originally collected in 1966, B. scabrella was one of several species previously considered to be forms of Banksia sphaerocarpa, before it was finally described by banksia expert Alex George in his 1981 revision of the genus. Like many members of the Abietinae, it is rarely seen in cultivation; however, it has been described as having horticultural potential. (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...)
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Inflorescence
Banksia speciosa, commonly known as the showy banksia, is a species of large shrub or small tree in the familyProteaceae. It is found on the south coast of Western Australia between Hopetoun (34° S 120° E) and Point Culver (33° S 124° E), growing on white or grey sand in shrubland. Reaching up to 8 m (26 ft) in height, it is a single-stemmed plant that has thin leaves with prominent triangular 'teeth' along each margin, which are 20–45 cm (7.9–17.7 in) long and 2–4 cm (0.8–1.6 in) wide. The prominent cream-yellow flower spikes known as inflorescences appear throughout the year. As they age they develop up to 20 follicles each that store seeds until opened by fire. Though widely occurring, the species is highly sensitive to dieback and large populations of plants have succumbed to the disease.
Collected and described by Robert Brown in the early 19th century, B. speciosa is classified in the seriesBanksia within the genus. Its closest relative is B. baxteri. B. speciosa plants are killed by bushfire, and regenerate from seed. The flowers attract nectar- and insect-feeding birds, particularly honeyeaters, and a variety of insects. In cultivation, B. speciosa grows well in a sunny location on well-drained soil in areas with dry summers. It cannot be grown in areas with humid summers, though it has been grafted onto Banksia serrata or B. integrifolia. (Full article...)
Ficus obliqua, commonly known as the small-leaved fig, is a tree in the family Moraceae, native to eastern Australia, New Guinea, eastern Indonesia to Sulawesi and islands in the southwestern Pacific Ocean. Previously known for many years as Ficus eugenioides, it is a banyan of the genus Ficus, which contains around 750 species worldwide in warm climates, including the edible fig (Ficus carica). Beginning life as a seedling, which grows on other plants (epiphyte) or on rocks (lithophyte), F. obliqua can grow to 60 m (200 ft) high and nearly as wide with a pale grey buttressed trunk, and glossy green leaves.
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 Aoraki / 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 2023 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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Brachychiton rupestris (commonly known as the narrow-leaved bottle tree or Queensland bottle tree) is a tree in the familyMalvaceae, endemic to Queensland, Australia. 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...)
Banksia oblongifolia, commonly known as the fern-leaved, dwarf or rusty banksia, is a species in the plant genusBanksia. Found along the eastern coast of Australia from Wollongong, New South Wales in the south to Rockhampton, Queensland in the north, it generally grows in sandy soils in heath, open forest or swamp margins and wet areas. A many-stemmed shrub up to 3 m (9.8 ft) high, it has leathery serrated leaves and rusty-coloured new growth. The yellow flower spikes, known as inflorescences, most commonly appear in autumn and early winter. Up to 80 follicles, or seed pods, develop on the spikes after flowering. Banksia oblongifolia resprouts from its woody lignotuber after bushfires, and the seed pods open and release seed when burnt, the seed germinating and growing on burnt ground. Some plants grow between fires from seed shed spontaneously.
Spanish botanist Antonio José CavanillesdescribedB. oblongifolia in 1800, though it was known as Banksia aspleniifolia in New South Wales for many years. However, the latter name, originally coined by Richard Anthony Salisbury, proved invalid, and Banksia oblongifolia has been universally adopted as the correct scientific name since 1981. Two varieties were recognised in 1987, but these have not been generally accepted. A wide array of mammals, birds, and invertebrates visit the inflorescences. Though easily grown as a garden plant, it is not commonly seen in horticulture. (Full article...)
Banksia brownii, commonly known as feather-leaved banksia or Brown's banksia, is a species of shrub that grows in southwestWestern Australia. A plant with fine feathery leaves and large red-brown flower spikes, it usually grows as an upright bush around two metres (6.6 ft) high, but can also occur as a small tree or a low spreading shrub. First collected in 1829 and published the following year, it is placed in Banksiasubgenus Banksia, section Oncostylis, series Spicigerae. There are two genetically distinct forms.
Banksia brownii occurs naturally only in two population clusters between Albany and the Stirling Range in southwest Western Australia. In the Stirling Range it occurs among heath on rocky mountain slopes; further south it occurs among jarrahwoodland in shallow nutrient-poor sand. It has been evaluated as critically endangered by the International Union for Conservation of Nature (IUCN); all major populations are threatened by Phytophthora cinnamomi dieback, a disease to which the species is highly susceptible. Other threats include loss of habitat, commercial exploitation and changes to the fire regime. Highly valued by Australia's horticultural and cut flower industries, B. brownii is widely cultivated in areas not exposed to dieback. It prefers a sheltered position in soil with good drainage, and must be provided with some moisture over summer. (Full article...)
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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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Cucurbita fruits come in an assortment of colors and sizes.
Cucurbita (Latin for 'gourd') is a genus of herbaceousfruits in the gourd family, Cucurbitaceae (also known as cucurbits or cucurbi), native to the Andes and Mesoamerica. Five edible species are grown and consumed for their flesh and seeds. They are variously known as squash, pumpkin, or gourd, depending on species, variety, and local parlance. Other kinds of gourd, also called bottle-gourds, are native to Africa and belong to the genus Lagenaria, which is in the same family and subfamily as Cucurbita, but in a different tribe; their young fruits are eaten much like those of the Cucurbita species.
Most Cucurbita species are herbaceous vines that grow several meters in length and have tendrils, but non-vining "bush" cultivars of C. pepo and C. maxima have also been developed. The yellow or orange flowers on a Cucurbita plant are of two types: female and male. The female flowers produce the fruit and the male flowers produce pollen. Many North and Central American species are visited by specialist beepollinators, but other insects with more general feeding habits, such as honey bees, also visit. (Full article...)
A cabbage generally weighs between 500 and 1,000 grams (1 and 2 lb). Smooth-leafed, firm-headed green cabbages are the most common, with smooth-leafed purple cabbages and crinkle-leafed savoy cabbages of both colours being rarer. Under conditions of long sunny days, such as those found at high northern latitudes in summer, cabbages can grow quite large. As of 2012[update], the heaviest cabbage was 62.71 kilograms (138 lb 4 oz). Cabbage heads are generally picked during the first year of the plant's life cycle, but plants intended for seed are allowed to grow a second year and must be kept separate from other cole crops to prevent cross-pollination. Cabbage is prone to several nutrient deficiencies, as well as to multiple pests, and bacterial and fungal diseases. (Full article...)
An ethylene signal transduction pathway. Ethylene permeates the cell membrane and binds to a gasoreceptor on the endoplasmic reticulum. The gasoreceptor releases the repressed EIN2. This then activates a signal transduction pathway which activates regulatory genes that eventually trigger an ethylene response. The activated DNA is transcribed into mRNA which is then translated into a functional enzyme that is used for ethylene biosynthesis. Ethylene (CH 2=CH 2) is an unsaturatedhydrocarbon gas (alkene) acting as a naturally occurring plant hormone. It is the simplest alkene gas and is the first gas known to act as a hormone. It acts at trace levels throughout the life of the plant by stimulating or regulating the ripening of fruit, the opening of flowers, the abscission (or shedding) of leaves and, in aquatic and semi-aquatic species, promoting the 'escape' from submergence by means of rapid elongation of stems or leaves. This escape response is particularly important in rice farming. Commercial fruit-ripening rooms use "catalytic generators" to make ethylene gas from a liquid supply of ethanol. Typically, a gassing level of 500 to 2,000 ppm is used, for 24 to 48 hours. Care must be taken to control carbon dioxide levels in ripening rooms when gassing, as high temperature ripening (20 °C; 68 °F) has been seen to produce CO2 levels of 10% in 24 hours. (Full article...)
The name "ragweed" is derived from "ragged" + "weed," coming from the ragged appearance of the plant's leaves. Other common names include bursages and burrobrushes. The genus name is from the Greekambrosia, meaning "food or drink of immortality". (Full article...)
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Reconstruction of Rhynia gwynne-vaughanii
The rhyniophytes are a group of extinct early vascular plants that are considered to be similar to the genus Rhynia, found in the Early Devonian (around 420 to 393 million years ago). Sources vary in the name and rank used for this group, some treating it as the class Rhyniopsida, others as the subdivision Rhyniophytina or the division Rhyniophyta. The first definition of the group, under the name Rhyniophytina, was by Banks, since when there have been many redefinitions, including by Banks himself. "As a result, the Rhyniophytina have slowly dissolved into a heterogeneous collection of plants ... the group contains only one species on which all authors agree: the type species Rhynia gwynne-vaughanii". When defined very broadly, the group consists of plants with dichotomously branched, naked aerial axes ("stems") with terminal spore-bearing structures (sporangia). The rhyniophytes are considered to be stem group tracheophytes (vascular plants). (Full article...)
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The hybrid tea rose, 'Peace' Garden roses are predominantly hybridroses that are grown as ornamental plants in private or public gardens. They are one of the most popular and widely cultivated groups of flowering plants, especially in temperate climates. An enormous number of garden cultivars has been produced, especially over the last two centuries, though roses have been known in the garden for millennia beforehand. While most garden roses are grown for their flowers, often in dedicated rose gardens, some are also valued for other reasons, such as having ornamental fruit, providing ground cover, or for hedging.
The cultivars are classified in a number of different and overlapping ways, generally without much reference to strict botanical principles. Taking overall size and shape, the most common type is the bush rose, a rounded plant from 2 foot up to about 7 foot tall, above which height roses generally fall into the "'climbing and rambling'" class, the latter spreading wider; support is needed for these. There are also miniature roses, generally small bushes, and low sprawling ground cover roses, both up to about 15 inches tall. Most modern roses are propagated by budding onto rootstocks much closer to wild species; in "standard" shapes there is a single bare stem, with the graft at the top of that. Shrub roses are a rather loose category that include some of the original species and cultivars closely related to them, plus cultivars that grow rather larger than most bush roses. Technically all roses are shrubs. In terms of ancestry, roses are often divided into three main groups: Wild, Old Garden, and Modern Garden roses, with many subdivisions of these. (Full article...)
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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 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.
The evolution of plants has resulted in a wide range of complexity, from the earliest algal mats of unicellular archaeplastids evolved through endosymbiosis, through multicellular marine and freshwatergreen algae, to spore-bearing terrestrial bryophytes, lycopods and ferns, and eventually to the complex seed-bearing gymnosperms and angiosperms (flowering plants) of today. While many of the earliest groups continue to thrive, as exemplified by red and green algae in marine environments, more recently derived groups have displaced previously ecologically dominant ones; for example, the ascendance of flowering plants over gymnosperms in terrestrial environments.
There is evidence that cyanobacteria and multicellular thalloid eukaryotes lived in freshwater communities on land as early as 1 billion years ago, and that communities of complex, multicellular photosynthesizing organisms existed on land in the late Precambrian, around 850 million years ago. (Full article...)
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Only a few of the many varieties of potato are commercially grown; others are heirlooms. 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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Redcurrants, a type of berry derived from a simple (one-locule) inferior ovary In botany, a berry is a fleshy fruit without a drupe (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.
Fruit tree propagation is usually carried out vegetatively (non-sexually) by grafting or budding a desired variety onto a suitable rootstock.
Perennial plants can be propagated either by sexual or vegetative means. Sexual reproduction begins when a male germ cell (pollen) from one flower fertilises a female germ cell (ovule, incipient seed) of the same species, initiating the development of a fruit containing seeds. Each seed, when germinated, can grow to become a new specimen tree. However, the new tree inherits characteristics of both its parents, and it will not grow true to the variety of either parent from which it came. That is, it will be a fresh individual with an unpredictable combination of characteristics of its own. Although this is desirable in terms of producing novel combinations from the richness of the gene pool of the two parent plants (such sexual recombination is the source of new cultivars), only rarely will the resulting new fruit tree be directly useful or attractive to the tastes of humankind. Most new plants will have characteristics that lie somewhere between those of the two parents. (Full article...)
Plant milk is a category of non-dairy beverages made from a water-based plantextract for flavoring and aroma. Nut milk is a subcategory made from nuts, while other plant milks may be created from grains, pseudocereals, legumes, seeds or endosperm. Plant-based milks are consumed as alternatives to dairy milk and provide similar qualities, such as a creamy mouthfeel, as well as a bland or palatable taste. Many are sweetened or flavored (e.g., vanilla).
As of 2021, there were about 17 different types of plant milks, of which almond, oat, soy, coconut and pea are the highest-selling worldwide. Production of plant milks—particularly soy, oat, and pea milks—can offer environmental advantages over animal milks in terms of greenhouse gas emissions and land and water use. (Full article...)
The gymnosperms (/ˈdʒɪmnəˌspɜːrmz,-noʊ-/ⓘnə-spurmz, -noh-; lit.'revealed seeds') are a group of woody, perennial seed-producing plants, typically lacking the protective outer covering which surrounds the seeds in flowering plants, that include conifers, cycads, Ginkgo, and gnetophytes, forming the clade Gymnospermae. The term gymnosperm comes from the composite word in Greek: γυμνόσπερμος (γυμνός, gymnos, 'naked' and σπέρμα, sperma, 'seed'), and literally means 'naked seeds'. The name is based on the unenclosed condition of their seeds (called ovules in their unfertilized state). The non-encased condition of their seeds contrasts with the seeds and ovules of flowering plants (angiosperms), which are enclosed within an ovary. Gymnosperm seeds develop either on the surface of scales or leaves, which are often modified to form cones, or on their own as in yew, Torreya, and Ginkgo.
The life cycle of a gymnosperm involves alternation of generations, with a dominant diploidsporophyte phase, and a reduced haploidgametophyte phase, which is dependent on the sporophytic phase. The term "gymnosperm" is often used in paleobotany to refer to (the paraphyletic group of) all non-angiosperm seed plants. In that case, to specify the modern monophyletic group of gymnosperms, the term Acrogymnospermae is sometimes used. (Full article...)
The arrival of humans around 50,000 years ago and the settlement by Europeans from 1788, has had a significant impact on the flora. The use of fire-stick farming by Aboriginal people led to significant changes in the distribution of plant species over time, and the large-scale modification or destruction of vegetation for agriculture and urban development since 1788 has altered the composition of most terrestrial ecosystems, leading to the extinction of 61 plant species by 2006, and endangering over 1000 more. (Full article...)
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Rice plant (Oryza sativa) with branched panicles containing many grains on each stem Rice is a cereal grain and in its domesticated form is the staple food of over half of the world's population, particularly in Asia and Africa. Rice is the seed of the grass species Oryza sativa (Asian rice)—or, much less commonly, Oryza glaberrima (African rice). Asian rice was domesticated in China some 13,500 to 8,200 years ago; African rice was domesticated in Africa about 3,000 years ago. Rice has become commonplace in many cultures worldwide; in 2021, 787 million tons were produced, placing it fourth after sugarcane, maize, and wheat. Only some 8% of rice is traded internationally. China, India, and Indonesia are the largest consumers of rice. A substantial amount of the rice produced in developing nations is lost after harvest through factors such as poor transport and storage. Rice yields can be reduced by pests including insects, rodents, and birds, as well as by weeds, and by diseases such as rice blast. Traditional rice polycultures such as rice-duck farming, and modern integrated pest management seek to control damage from pests in a sustainable way.
Dry rice grain is milled to remove the outer layers; depending on how much is removed, products range from brown rice to rice with germ and white rice. Some is parboiled to make it easy to cook. Rice contains no gluten; it provides protein but not all the essential amino acids needed for good health. Rice of different types is eaten around the world. The composition of starch components within the grain, amylose and amylopectin, gives it different texture properties. Long-grain rice, from the Indica cultivar, tends to stay intact on cooking, and is dry and fluffy. The aromatic rice varieties such as basmati and jasmine, are widely used in Asian cooking, and distinguished by their bold and nutty flavor profile. Medium-grain rice, from either the Japonica or Indica cultivar, or a hybrid of both, is moist and tender and tends to stick together. Its varieties include Calrose, which founded the Californian rice industry, Carnaroli, attributed as the king of Italian rice due to its excellent cooking properties, and black rice, which looks dark purple due to high levels of anthocyanins, and is also known as forbidden rice as it was reserved for the consumption of the royal family in ancient China. Short-grain rice, primarily from the Japonica cultivar, has an oval appearance and sticky texture. It is featured heavily in Japanese cooking such as sushi (with rice such as Koshihikari, Hatsushimo, and Sasanishiki, unique to different regions of climate and geography in Japan), as it keeps its shape when cooked. It is also used for sweet dishes such as mochi (with glutinous rice), and in European cuisine such as risotto (with arborio rice) and paella (with bomba rice, which is actually an Indica variety). Cooked white rice contains 29% carbohydrate and 2% protein, with some manganese. Golden rice is a variety produced by genetic engineering to contain vitamin A. (Full article...)
Bernard de Jussieu was born in Lyon. He took a medical degree at Montpellier and began practice in 1720, but finding the work uncongenial he gladly accepted his brother's invitation to Paris in 1722, when he succeeded Sebastien Vaillant (1669–1722) as sub-demonstrator of plants in the Jardin des Plantes. In 1725, he brought out a new edition of Joseph Pitton de Tournefort's Histoire des plantes qui naissent aux environs de Paris, 2 vols., which was afterwards translated into English by John Martyn, the original work being incomplete. In the same year he was admitted into the French Academy of Sciences, and communicated several papers to that body. (Full article...)
These are good articles, which meet a core set of high editorial standards..
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Postelsia palmaeformis growing in its native habitat at low tide
Postelsia palmaeformis, also known as the sea palm (not to be confused with the southern sea palm) or palm seaweed, is a species of kelp and classified within brown algae. It is the only known species in the genus Postelsia. The sea palm is found along the western coast of North America, on rocky shores with constant waves. It is one of the few algae that can survive and remain erect out of the water; in fact, it spends most of its life cycle exposed to the air. It is an annual, and edible, though harvesting of the alga is discouraged due to the species' sensitivity to overharvesting. (Full article...)
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Mereschkowski c. 1885
Konstantin Sergeevich Mereschkowski (Russian: Константи́н Серге́евич Мережко́вский, IPA:[mʲɪrʲɪˈʂkofskʲɪj]; 4 August 1855 [O.S. 23 July] – 9 January 1921) was a Russianbiologist and botanist, active mainly around Kazan, whose research on lichens led him to propose the theory of symbiogenesis – that larger, more complexcells (of eukaryotes) evolved from the symbiotic relationship between less complex ones. He presented this theory in 1910, in his work, The Theory of Two Plasms as the Basis of Symbiogenesis, a New Study of the Origins of Organisms, although the fundamentals of the idea had already appeared in his earlier 1905 work, The nature and origins of chromatophores in the plant kingdom. (Full article...)
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Tephrosia purpurea is a species of flowering plant in the family Fabaceae. It grows in poor soils as a common wasteland weed and has a pantropical distribution. It is a type of legume native to south-western Asia (the Levant, Arabian Peninsula, Socotra, Iran, Pakistan, India and Sri Lanka) and north-eastern Africa (Egypt, Sudan, Ethiopia, Eritrea, Djibouti, Somalia).
The leaflets of the plant are obovate-oblong and equal-sided, and of a silky texture. The fruits (legumes) are typically 1 to 2 in (25 to 51 mm) long and contain six or seven brownish seeds. The species typically grows in areas where the soils are relatively deep, especially in semi-arid and wadi areas, and on terraces and slight inclines and hills. (Full article...)
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Brooklyn Botanic Garden
Brooklyn Botanic Garden (BBG) is a botanical garden in the borough of Brooklyn in New York City. The botanical garden occupies 52 acres (21 ha) in central Brooklyn, close to Mount Prospect Park, Prospect Park, and the Brooklyn Museum. Designed by the Olmsted Brothers, BBG holds over 14,000 taxa of plants and has over 800,000 visitors each year. It includes a number of specialty gardens, plant collections, and structures. BBG hosts numerous educational programs, plant-science and conservation, and community horticulture initiatives, in addition to a herbarium collection.
The site of Brooklyn Botanic Garden was first designated in 1897, following three proposals for botanic gardens in Brooklyn in the 19th century. BBG opened in May 1911, on the site of an ash dump, and was initially operated by the Brooklyn Institute. Most of BBG's expansions were carried out over the next three decades under the tenure of its first director, C. Stuart Gager. BBG began operating three additional sites in the New York metropolitan area in the 1950s and 1960s, while its main garden in Brooklyn fell into decline. The original Brooklyn Botanic Garden was expanded and restored substantially starting in the 1980s, and additional structures were built through the 2010s. (Full article...)
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Spelt (Triticum spelta), also known as dinkel wheat is a species of wheat. It is a relict crop, eaten in Central Europe and northern Spain. It is high in protein and may be considered a health food.
The Kew Herbarium (herbarium code: K) is one of the world's largest and most historically significant herbaria, housed at the Royal Botanic Gardens, Kew in London, England. Established in the 1850s on the ground floor of Hunter House, it has grown to maintain approximately seven million preserved plant specimens, including 330,000 type specimens. The herbarium's collections, which include specimens dating back to 1700, represent about 95% of known vascular plant genera and 60% of described fungi, with specimens collected over 260 years of botanical exploration. The herbarium processes around 5,000 specimen loans annually and hosts approximately 3,000 visitor-days of research visits each year, supporting a wide range of botanical research.
The herbarium's development has been closely tied to British botanical exploration and colonial expansion, with contributions from influential directors like Sir Joseph Dalton Hooker and major acquisitions including the Gay Herbarium. Research at the herbarium has contributed to botanical taxonomy, with publications such as the Index Kewensis, initiated with funding from Charles Darwin in 1882, and the Kew Record. The facility has undergone several major expansions since its first purpose-built wing was constructed in 1877, with Victorian architecture that includes spiral staircases, iron columns, and vast handcrafted wooden cupboards. In 2022, the herbarium initiated a £29 million digitisation project to produce high-resolution images of its collection, with a target completion date of 2026. (Full article...)
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Cowpeas
The cowpea (Vigna unguiculata) is an annualherbaceouslegume from the genus Vigna. Its tolerance for sandy soil and low rainfall have made it an important crop in the semiarid regions across Africa and Asia. It requires very few inputs, as the plant's root nodules are able to fix atmospheric nitrogen, making it a valuable crop for resource-poor farmers and well-suited to intercropping with other crops. The whole plant is used as forage for animals, with its use as cattle feed likely responsible for its name.
Four subspecies of cowpeas are recognised, of which three are cultivated. A high level of morphological diversity is found within the species with large variations in the size, shape, and structure of the plant. Cowpeas can be erect, semierect (trailing), or climbing. The crop is mainly grown for its seeds, which are high in protein, although the leaves and immature seed pods can also be consumed. (Full article...)
This grape variety appeared in France in the 17th century as a result of natural crossbreeding. Its popularity is often attributed to its ease of cultivation—the grapes have thick skins and the vines are hardy and naturally low yielding, budding late to avoid frost and resistant to viticulture hazards. (Full article...)
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Ornithogalum umbellatum, the garden star-of-Bethlehem, grass lily, nap-at-noon, or eleven-o'clock lady, is a perennialbulbousflowering plant in the asparagus family (Asparagaceae). O. umbellatum is a relatively short plant, occurring in tufts of basal linear leaves, producing conspicuous white flowers, in a stellate pattern, in mid to late spring. The flowers open late in the day (hence some of its common names), but when closed have a green stripe on the outside. It is native throughout southern and central Europe, and north-western Africa. O. umbellatum is often grown as a garden ornamental, but in North America and other areas it has escaped cultivation and can be found in many areas, where it may be considered an invasive weed. Parts of the plant are considered poisonous, but are used in some regional cuisines. Essences are also sold as patent remedies. O. umbellatum has been depicted in art by artists such as Leonardo da Vinci, and folklore has suggested it originally grew from fragments of the star of Bethlehem, hence its horticultural name. (Full article...)
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Einar Du Rietz in 1932
Gustaf Einar Du Rietz (25 April 1895 – 7 March 1967) was a Swedish botanist and lichenologist. His research interests included plant ecology, lichen taxonomy, and biogeography. He was a leading figure in the Uppsala school of phytosociology–the study of groups of species of plants that are usually found together–and is recognised for his role in advancing this field of science and for mentoring future lichenologists. He led the Swedish Australasian Botanical Expedition of 1926–27, a seven-month research tour of various locations. He was married to Greta Sernander, who was also a lichenologist. During the expedition, Du Rietz and his wife researched the vegetation in New Zealand, Australia, and Java, focusing on mountain lichens and their potential as bioindicators for environmental conditions. They collected around 3000 specimens, contributing significantly to the study of bipolar lichens and forest ecology, despite challenges in processing all the samples upon return to Sweden. Several species have been named in his honour. In 1949, Du Rietz was elected to the Royal Swedish Academy of Sciences and contributed significantly to nature conservation efforts in Sweden. (Full article...)
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Dracophyllum traversii, commonly known as mountain neinei, grass tree, and pineapple tree is a species of flowering plant in the heath family Ericaceae. It is a deciduous tree (or, in some cases, a shrub) endemic to New Zealand. It reaches a height of 0.2–13 m (0.66–42.65 ft) and has leaves which form tufts at the end of its branches. It has a lifespan of between 500 and 600 years.
Similar to some other Dracophyllum species, it has a candelabra-shaped canopy; long, thin, green leaves; and a prominent pyramid-shaped inflorescence. It has tiny red flowers, between 500 and 3000 on each panicle, and equally tiny reddish-brown dry fruit. D. traversii inhabits a variety of forest and shrubland types, from lowland to subalpine, in gorges, on cliffs, and on mountainsides. It has a range that stretches from Waima forest at the top of New Zealand's North Island, down to Otago and Fiordland in the South Island. (Full article...)
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Tigridia conchiflora var. 'Watkinsoni', a lily first hybridised by John Horsefield John Horsefield (18 July 1792 – 6 March 1854) was an English handloom weaver and amateur botanist after whom the daffodilNarcissus 'Horsfieldii' is named. Horsefield had little formal schooling, and acquired most of his botanical knowledge through self-study and involvement in local botanical groups, which provided a venue for working class people to share knowledge, in part by pooling money to purchase books.
Horsefield founded one such society, the Prestwich Botanical Society, and was later president of a larger botanical society covering a wide area around north Manchester. He made several botanical discoveries and cultivated two new plants. A number of his writings about the working class and also some poetry were published, but nothing concerning botany other than in connection with the subject of the working class. He lived most of his life near Whitefield in Lancashire, in dire poverty. At the time of his death he had been married for 42 years and had fathered eleven children. (Full article...)
Cicuta, commonly known as water hemlock, is a genus of four species of highly poisonous plants in the family Apiaceae. They are perennialherbaceous plants which grow up to 2.5 meters (8 ft) tall, having distinctive small green or white flowers arranged in an umbrella shape (umbel). Plants in this genus may also be referred to as cowbane or poison parsnip. Cicuta is native to temperate regions of the Northern Hemisphere, mainly North America and Europe, typically growing in wet meadows, along streambanks and other wet and marshy areas. These plants bear a close resemblance to other members in the family Apiaceae and may be confused with a number of edible or poisonous plants. The common name hemlock may also be confused with poison hemlock (Conium maculatum), or with the Hemlock tree.
Water hemlock is considered one of North America's most toxic plants, being highly poisonous to humans. Three members of the genus contain a toxin named cicutoxin which causes central nervous system stimulatory effects including seizures following ingestion. Medical treatment of poisoning may include the use of activated charcoal to decrease gastrointestinal absorption of the toxic principle along with supportive care including anticonvulsant drugs such as a benzodiazepine. High doses of anticonvulsant medicine are often required to halt seizure activity and further medical care including intubation and mechanical ventilation may be required. (Full article...)
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In mathematics, the three-gap theorem, three-distance theorem, or Steinhaus conjecture states that if one places n points on a circle, at angles of θ, 2θ, 3θ, ... from the starting point, then there will be at most three distinct distances between pairs of points in adjacent positions around the circle. When there are three distances, the largest of the three always equals the sum of the other two. Unless θ is a rational multiple of π, there will also be at least two distinct distances.
This result was conjectured by Hugo Steinhaus, and proved in the 1950s by Vera T. Sós, János Surányi [hu], and Stanisław Świerczkowski; more proofs were added by others later. Applications of the three-gap theorem include the study of plant growth and musical tuning systems, and the theory of light reflection within a mirrored square. (Full article...)
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John Hunter Thomas (March 26, 1928 – July 20, 1999) was an American botanist, professor of biological sciences at Stanford University, curator and director of the Dudley Herbarium, and joint curator at the California Academy of Sciences. He was known for his study of plants in the Sonoran Desert, the Santa Cruz Mountains, and the Alaska North Slope, and for his history of botanical exploration in Washington, Oregon, and California. His doctoral research on the plants of the Santa Cruz Mountains was published as a guide to the vascular plants of coastal, central California, and was recognized as a standard reference work for regional flora. It was used for decades as teaching material for courses in systematic botany and the ecology of vascular plants at Stanford. Thomas helped establish the Jasper Ridge Biological Preserve and was a primary contributor to what later became the Jasper Ridge Oakmead Herbarium (JROH). In total, Thomas collected more than 20,000 plant specimens for herbaria throughout his career. (Full article...)
... that police officers had to be flown in by helicopter to seize hundreds of thousands of dollars' worth of cannabis plants found growing illegally in Jerrawangala National Park?
... that 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?
The following are images from various plant-related articles on Wikipedia.
Image 1The 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 4Structure 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 7A 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 8The food we eat comes directly or indirectly from plants such as rice. (from Botany)
Image 9The 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 10A 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 11A nineteenth-century illustration showing the morphology of the roots, stems, leaves and flowers of the rice plant Oryza sativa (from Botany)
Image 12Thale cress, Arabidopsis thaliana, the first plant to have its genome sequenced, remains the most important model organism. (from Botany)
Image 131 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 16A botanist preparing a plant specimen for mounting in the herbarium (from Botany)
Image 17The 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 20Echeveria glauca in a Connecticut greenhouse. Botany uses Latin names for identification; here, the specific name glauca means blue. (from Botany)
Image 21Structure of a plant cell (from Plant cell)
Image 22The Linnaean Garden of Linnaeus' residence in Uppsala, Sweden, was planted according to his Systema sexuale. (from Botany)
Image 27Paper chromatography of some spinach leaf extract shows the various pigments present in their chloroplasts: yellowish xanthophylls, greenish chlorophylls a and b. (from Botany)
Image 28Leaf lamina. The megaphyllous leaf architecture arose multiple times in different plant lineages (from Evolutionary history of plants)
Image 29This is an electron micrograph of the epidermal cells of a Brassica chinensis leaf. The stomates are also visible. (from Plant cell)
Image 31The trunk of early tree fern Psaronius, showing internal structure. The top of the plant would have been to the left of the image (from Evolutionary history of plants)