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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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...)
Banksia integrifolia, commonly known as the coast banksia, is a species of tree that grows along the east coast of Australia. One of the most widely distributed Banksia species, it occurs between Victoria and Central Queensland in a broad range of habitats, from coastal dunes to mountains. It is highly variable in form, but is most often encountered as a tree up to 25 metres (82 ft) in height. Its leaves have dark green upper surfaces and white undersides, a contrast that can be striking on windy days.
The title page of the 1877 edition of Fertilisation of Orchids
Fertilisation of Orchids is a book by English naturalist Charles Darwin published on 15 May 1862 under the full explanatory title On the Various Contrivances by Which British and Foreign Orchids Are Fertilised by Insects, and On the Good Effects of Intercrossing. Darwin's previous book, On the Origin of Species, had briefly mentioned evolutionary interactions between insects and the plants they fertilised, and this new idea was explored in detail. Field studies and practical scientific investigations that were initially a recreation for Darwin—a relief from the drudgery of writing—developed into enjoyable and challenging experiments. Aided in his work by his family, friends, and a wide circle of correspondents across Britain and worldwide, Darwin tapped into the contemporary vogue for growing exotic orchids.
The book was his first detailed demonstration of the power of natural selection, and explained how complex ecological relationships resulted in the coevolution of orchids and insects. The view has been expressed that the book led directly or indirectly to all modern work on coevolution and the evolution of extreme specialisation. It influenced botanists, and revived interest in the neglected idea that insects played a part in pollinating flowers. It opened up the new study areas of pollination research and reproductive ecology, directly related to Darwin's ideas on evolution, and supported his view that natural selection led to a variety of forms through the important benefits achieved by cross-fertilisation. Although the general public showed less interest and sales of the book were low, it established Darwin as a leading botanist. Orchids was the first in a series of books on his innovative investigations into plants. (Full article...)
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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.
Alloxylon pinnatum, known as Dorrigo waratah, is a tree of the family Proteaceae found in warm-temperate rainforest of south-east Queensland and northern New South Wales in eastern Australia. It has shiny green leaves that are either pinnate (lobed) and up to 30 cm (12 in) long, or lanceolate (spear-shaped) and up to 15 cm (5.9 in) long. The prominent pinkish-red flower heads, known as inflorescences, appear in spring and summer; these are made up of 50 to 140 individual flowers arranged in corymb or raceme. These are followed by rectangular woody seed pods, which bear two rows of winged seeds.
Known for many years as Oreocallis pinnata, it was transferred to the new genus Alloxylon by Peter Weston and Mike Crisp in 1991. This genus contains the four species previously classified in Oreocallis that are found in Australasia. Its terminal globular flowers indicate that the species is pollinated by birds. Classified as near threatened under the Queensland Nature Conservation Act 1992, the Dorrigo waratah has proven difficult to keep alive in cultivation. (Full article...)
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Banksia lemanniana, the yellow lantern banksia or Lemann's banksia, is a species of flowering plant in the familyProteaceae, native to Western Australia. It generally grows as an open woody shrub or small tree to 5 m (16 ft) high, with stiff serrated leaves and unusual hanging inflorescences. Flowering occurs over summer, the greenish buds developing into oval flower spikes before turning grey and developing the characteristic large woody follicles. It occurs within and just east of the Fitzgerald River National Park on the southern coast of the state. B. lemanniana is killed by bushfire and regenerates from seed.
Described by Swiss botanist Carl Meissner in 1856, Banksia lemanniana was named in honour of English botanist Charles Morgan Lemann. It is one of three or four related species all with pendent inflorescences, which is an unusual feature of banksias. No subspecies are recognised. Banksia lemanniana is classified as Not Threatened under the Wildlife Conservation Act of Western Australia. Unlike many Western Australian banksias, it appears to have some resistance to dieback from the soil-borne water mouldPhytophthora cinnamomi, and is one of the easier Western Australian species to grow in cultivation. (Full article...)
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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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Symphyotrichum lateriflorum (formerly Aster lateriflorus) is a species of flowering plant in the aster family (Asteraceae). Commonly known as calico aster, starved aster, and white woodland aster, it is native to eastern and central North America. It is a perennial and herbaceous plant that may reach heights up to 120 centimeters (4 feet) and widths up to 30 centimeters (1 foot).
The flowers of calico aster are small compared to most Symphyotrichum species. They have an average of 7–15 short white ray florets, which are rarely tinted pink or purple. The flower centers, composed of disk florets, begin as cream to yellow and often become pink, purple, or brown as they mature. There are roughly 8–16 disk florets, each with five lobes that strongly reflex (bend backwards) when open. The mostly hairless leaves have a characteristic hairy midrib on their back faces, and branching is usually horizontal or in what can appear to be a zigzag pattern. Flower heads grow along one side of the branches and sometimes in clusters at the ends. (Full article...)
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Inflorescence
Banksia epica is a shrub that grows on the south coast of Western Australia. A spreading bush with wedge-shaped serrated leaves and large creamy-yellow flower spikes, it grows up to 3½ metres (11½ ft) high. It is known only from two isolated populations in the remote southeast of the state, near the western edge of the Great Australian Bight. Both populations occur among coastal heath on cliff-top dunes of siliceous sand.
One of the most recently described Banksia species, it was probably seen by Edward John Eyre in 1841, but was not collected until 1973, and was only recognised as a distinct species in 1988. There has been very little research on the species since then, so knowledge of its ecology and cultivation potential is limited. It is placed in Banksia ser. Cyrtostylis, alongside its close relative, the well-known and widely cultivated B. media (southern plains banksia). (Full article...)
In nature, B. sceptrum grows in deep yellow or pale red sand in tall shrubland, commonly on dunes, being found as a shrub to 5 metres (16 ft) high, though often smaller in exposed areas. It is killed by fire and regenerates by seed, the woody follicles opening with fire. B. sceptrum is one of the most striking yellow-flowered banksias of all. Its tall bright yellow spikes, known as inflorescences, are terminal and well displayed. Flowering is in summer, mainly December and January, though flowers are occasionally seen at other times. (Full article...)
Banksia blechnifolia is a species of flowering plant in the genusBanksia found in Western Australia. It was first described by Victorian state botanist Ferdinand von Mueller in 1864, and no subspecies are recognised. It gained its specific name as its leaves are reminiscent of a fern (Blechnum). B. blechnifolia is one of several closely related species that grow as prostrate shrubs, with horizontal stems and leathery, upright leaves. The red-brown flower spikes, known as inflorescences, are up to 20 centimetres (8 in) high and appear from September to November in the Australian spring. As the spikes age, each turns grey and develops as many as 25 woody seed pods, known as follicles.
Insects such as bees, wasps, ants and flies pollinate the flowers. Found in sandy soils in the south coastal region of Western Australia in the vicinity of Lake King, B. blechnifolia is non-lignotuberous, regenerating by seed after bushfire. The plant adapts readily to cultivation, growing in well-drained sandy soils in sunny locations. It is suitable for rockeries and as a groundcover. (Full article...)
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Persoonia lanceolata, commonly known as lance-leaf geebung, is a shrub native to New South Wales in eastern Australia. It reaches 3 m (10 ft) in height and has smooth grey bark and bright green foliage. Its small yellow flowers grow on racemes and appear in the austral summer and autumn (January to April), followed by green fleshy fruits (known as drupes) which ripen the following spring (September to October). Within the genus Persoonia, P. lanceolata belongs to the lanceolata group of 58 closely related species. It interbreeds with several other species found in its range.
The species is usually found in dry sclerophyll forest on sandstone-based nutrient-deficient soil. It has adapted to a fire-prone environment; plants lost in bushfires can regenerate through a ground-stored seed bank. Seedlings mostly germinate within two years of fires. Several species of native bee of the genus Leioproctus pollinate the flowers. Swamp wallabies are a main consumer of its fruit, and the seeds are spread in wallaby faeces. Its lifespan ranges from 25 to 60 years, though difficulties in propagation have seen low cultivation rates. (Full article...)
Banksia serrata, commonly known as the saw banksia, the old man banksia, the saw-tooth banksia or the red honeysuckle and as wiriyagan by the Cadigal people, is a species of woody shrub or tree of the genus Banksia, in the family Proteaceae. Native to the east coast of Australia, it is found from Queensland to Victoria with outlying populations on Tasmania and Flinders Island. Commonly growing as a gnarled tree up to 16 m (50 ft) in height, it can be much smaller in more exposed areas. This Banksia species has wrinkled grey bark, shiny dark green serrated leaves and large yellow or greyish-yellow flower spikes appearing over summer. The flower spikes, or inflorescences, turn grey as they age and pollinated flowers develop into large, grey, woody seed pods called follicles.
B. serrata is one of the four original Banksia species collected by Sir Joseph Banks in 1770, and one of four species published in 1782 as part of Carolus Linnaeus the Younger's original description of the genus. There are no recognised varieties, although it is closely related to Banksia aemula. Throughout its range, it grows exclusively in sandy soil, and is usually the dominant plant in scrubland or low woodland. B. serrata is pollinated by and provides food for a wide array of vertebrate and invertebrate animals in the autumn and winter months, and is an important source of food for honeyeaters. It is a common plant of parks and gardens. (Full article...)
Banksia sessilis, commonly known as parrot bush, is a species of shrub or tree in the plantgenusBanksia of the family Proteaceae. It had been known as Dryandra sessilis until 2007, when the genus Dryandra was sunk into Banksia. The Noongar peoples know the plant as budjan or butyak. Widespread throughout southwestWestern Australia, it is found on sandy soils over laterite or limestone, often as an understorey plant in open forest, woodland or shrubland. Encountered as a shrub or small tree up to 6 m (20 ft) in height, it has prickly dark green leaves and dome-shaped cream-yellow flowerheads. Flowering from winter through to late spring, it provides a key source of food—both the nectar and the insects it attracts—for honeyeaters in the cooler months, and species diversity is reduced in areas where there is little or no parrot bush occurring. Several species of honeyeater, some species of native bee, and the European honey bee seek out and consume the nectar, while the long-billed black cockatoo and Australian ringneck eat the seed. The life cycle of Banksia sessilis is adapted to regular bushfires. Killed by fire and regenerating by seed afterwards, each shrub generally produces many flowerheads and a massive amount of seed. It can recolonise disturbed areas, and may grow in thickets.
Banksia sessilis has a somewhat complicated taxonomic history. It was collected from King George Sound in 1801 and described by Robert Brown in 1810 as Dryandra floribunda, a name by which it was known for many years. However, Joseph Knight had published the name Josephia sessilis in 1809, which had precedence due to its earlier date, and the specific name was formalised in 1924. Four varieties are recognised. It is a prickly plant with little apparent horticultural potential; none of the varieties are commonly seen in cultivation. A profuse producer of nectar, B. sessilis is valuable to the beekeeping industry. (Full article...)
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Inflorescence with unopened buds (left), opened flowers (right)
Banksia marginata, commonly known as the silver banksia, is a species of tree or shrub in the family Proteaceae found throughout much of southeastern Australia. It ranges from the Eyre Peninsula in South Australia to north of Armidale, New South Wales, and across Tasmania and the islands of Bass Strait. It grows in various habitats, including Eucalyptus forest, scrub, heathland and moorland. Banksia marginata varies widely in habit, ranging from a 20-centimetre (7.9 in) shrub to a 12-metre (40 ft) tree. The narrow leaves are linear and the yellow inflorescences occur from late summer to early winter. These flower spikes fade to brown and then grey and develop woody follicles bearing the winged seeds. Originally described by Antonio José Cavanilles in 1800, further collections of B. marginata were designated as several separate species by Robert Brown in 1810. However, all were reclassified as a single species by George Bentham in 1870. No distinct subspecies have been recognised by Banksia expert Alex George, who nonetheless concedes that further work is needed.
Many species of bird, in particular honeyeaters, forage at the flower spikes, as do native and European honeybees. The response to bushfire varies. Some populations are serotinous: they are killed by fire and regenerate from large stores of seed, which have been held in cones in the plant canopy and are released after a fire. Others regenerate from underground lignotubers or suckers from lateral roots. Although it has been used for timber, Banksia marginata is most commonly seen as a garden plant, with dwarf forms being commercially propagated and sold. (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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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...)
Date palms reach up to 60–110 feet in height, growing singly or forming a clump with several stems from a single root system. Slow-growing, they can reach over 100years of age when maintained properly. Date fruits (dates) are oval-cylindrical, 3 to 7 centimetres (1 to 3 inches) long, and about 2.5 cm (1 in) in diameter, with colour ranging from dark brown to bright red or yellow, depending on variety. Containing 63-64% sugar by mass when dried (nutrition table), dates are consumed as sweet snacks on their own or with confections. (Full article...)
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Tropical coastline vegetation in Maui with Scaevola taccada bush in the foreground Tropical vegetation, plant life that occurs in climates that are warm year-round, is in general more biologically diverse than in other latitudes. Some tropical areas may receive abundant rain the whole year round, while others have long dry seasons which last several months and may vary in length and intensity with geographic location. These seasonal droughts have a great impact on the vegetation, such as in the Madagascar spiny forests.
Rainforest vegetation can often be categorized into five layers. The top layer is the emergents, the upper tree layer, with the largest and widest trees in all the forest, commonly 50 m (160 ft) and higher. These trees tend to have very large canopies so they can be fully exposed to sunlight. A layer below that is the canopy, or middle tree layer, averaging 30–40 m (98–131 ft) in height. Here there are more compact trees and vegetation. These trees, shaded, tend to be slenderer. The third layer is the lower tree area. These trees tend to be around 5–10 m (16–33 ft) high and tightly compacted. The trees found in the third layer include young trees with the potential to grow into larger canopy trees, and "palmoids" or "corner model trees". The fourth layer is the shrub layer beneath the tree canopy. This layer is mainly populated by sapling trees, shrubs, and seedlings. The fifth and lowest layer is the herb layer which is the forest floor, mainly bare except for various plants, mosses, lycopods and ferns. The forest floor is much more dense than above because of little sunlight and air movement. (Full article...)
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Vegetables in a market in the Philippines Vegetables are edible parts of plants that are consumed by humans or other animals as food. This original meaning is still commonly used, and is applied to plants collectively to refer to all edible plant matter, including flowers, fruits, stems, leaves, roots, and seeds. An alternative definition is applied somewhat arbitrarily, often by culinary and cultural tradition; it may include savoury fruits such as tomatoes and courgettes, flowers such as broccoli, and seeds such as pulses, but exclude foods derived from some plants that are fruits, flowers, nuts, and cereal grains.
Originally, vegetables were collected from the wild by hunter-gatherers and entered cultivation in several parts of the world, probably during the period 10,000 BC to 7,000 BC, when a new agricultural way of life developed. At first, plants that grew locally were cultivated, but as time went on, trade brought common and exotic crops from elsewhere to add to domestic types. Nowadays, most vegetables are grown all over the world as climate permits, and crops may be cultivated in protected environments in less suitable locations. China is the largest producer of vegetables, and global trade in agricultural products allows consumers to purchase vegetables grown in faraway countries. The scale of production varies from subsistence farmers supplying the needs of their family for food, to agribusinesses with vast acreages of single-product crops. Depending on the type of vegetable concerned, harvesting the crop is followed by grading, storing, processing, and marketing. (Full article...)
Safflower (Carthamus tinctorius), also false saffron, is a highly branched, herbaceous, thistle-like annual plant in the family Asteraceae. It is one of the world's oldest crops; today, it is commercially cultivated for vegetable oil extracted from the seeds. Plants are 30 to 150 cm (12 to 59 in) tall with globular flower heads having yellow, orange, or redflowers. Each branch will usually have from one to five flower heads containing 15 to 20 seeds per head. Safflower is native to arid environments having seasonal rain. It grows a deep taproot which enables it to thrive in such environments. (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...)
Flowering plants are plants that bear flowers and fruits, and form the cladeAngiospermae (/ˌændʒiəˈspərmiː/). The term angiosperm is derived from the Greek words ἀγγεῖον (angeion; 'container, vessel') and σπέρμα (sperma; 'seed'), meaning that the seeds are enclosed within a fruit. The group was formerly called Magnoliophyta.
A European honey bee pollinates a peach flower while collecting nectar. Pollination of fruit trees is required to produce seeds with surrounding fruit. It is the process of moving pollen from the anther to the stigma, either in the same flower or in another flower. Some tree species, including many fruit trees, do not produce fruit from self-pollination, so pollinizer trees are planted in orchards.
The pollination process requires a carrier for the pollen, which can be animal, wind, or human intervention (by hand-pollination or by using a pollen sprayer). Cross pollination produces seeds with a different genetic makeup from the parent plants; such seeds may be created deliberately as part of a selective breeding program for fruit trees with desired attributes. Trees that are cross-pollinated or pollinated via an insect pollinator produce more fruit than trees with flowers that just self-pollinate. In fruit trees, bees are an essential part of the pollination process for the formation of fruit. (Full article...)
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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...)
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A field after application of a herbicide Herbicides (US: /ˈɜːrbɪsaɪdz/, UK: /ˈhɜːr-/), also commonly known as weed killers, are substances used to control undesired plants, also known as weeds. Selective herbicides control specific weed species while leaving the desired crop relatively unharmed, while non-selective herbicides (sometimes called "total weed killers") kill plants indiscriminately. The combined effects of herbicides, nitrogen fertilizer, and improved cultivars has increased yields (per acre) of major crops by three to six times from 1900 to 2000.
In the United States in 2012, about 91% of all herbicide usage was, determined by weight, applied in agriculture. In 2012, world pesticide expenditures totaled nearly US$24.7 billion; herbicides were about 44% of those sales and constituted the biggest portion, followed by insecticides, fungicides, and fumigants. Herbicide is also used in forestry, where certain formulations have been found to suppress hardwood varieties in favor of conifers after clearcutting, as well as pasture systems. (Full article...)
It is a short-lived perennialmint-family herb growing 30–100 cm (12–39 in) tall with square stems, grayish canescent leaves that vary in shape and have serrated edges, fragrant small bilabiate flowers arranged in raceme spikes, and produces small three-sided nutlets containing one to four seeds. It was described by Carl Linnaeus in 1753, with no subspecies but multiple botanical synonyms, and its name—derived from medieval Latin—reflects its historical association with cats and various traditional names dating back to medieval England. (Full article...)
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Buxbaumia viridis
Buxbaumia (bug moss, bug-on-a-stick, humpbacked elves, or elf-cap moss) is a genus of twelve species of moss (Bryophyta). It was first named in 1742 by Albrecht von Haller and later brought into modern botanical nomenclature in 1801 by Johann Hedwig to commemorate Johann Christian Buxbaum, a German physician and botanist who discovered the moss in 1712 at the mouth of the Volga River. The moss is microscopic for most of its existence, and plants are noticeable only after they begin to produce their reproductive structures. The asymmetrical spore capsule has a distinctive shape and structure, some features of which appear to be transitional from those in primitive mosses to most modern mosses. (Full article...)
The city of Portland, Oregon, is ideal for growing roses outdoors due to its location within the marine west coastclimate region, its warm, dry summers and rainy but mild winters, and its heavy clay soils. Portland has been known as the City of Roses, or Rose City, since the late 19th or early 20th century, after Madame Caroline Testout, a large pink variety of hybrid tea rose bred in France, was introduced to the city. Thousands of rose bushes were planted, eventually lining 200 miles (320 km) of Portland's streets in preparation for the Lewis and Clark Centennial Exposition in 1905.
The Rose City Park neighborhood in northeast Portland was formed in 1907, the same year of the first annual Portland Rose Festival. During World War I, nursery owners in Portland began planning a large rose garden to protect European rose varieties from the war. The garden was established in Washington Park as the International Rose Test Garden in 1917. Today, the Portland Rose Festival takes place each June with a carnival, parades, and navy ships docked along the Tom McCall Waterfront Park to promote the city. The International Rose Test Garden is currently one of the oldest public rose test gardens in the United States, covering 4.5 acres (1.8 ha) with over 8,000 rose plants, and more than 550 different varieties. In 2003, Portland adopted the "City of Roses" as its official nickname. (Full article...)
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Leaf of Drosera capensis bending around a captured insect
Drosera capensis (/ˈdrɒsərəkəˈpɛnsɪs/), the Cape sundew, is a perennial rosette-forming carnivorous herb in the flowering plant family Droseraceae. It is native to the Cape region of South Africa, where it grows in permanently wet, nutrient-poor habitats. Its elongated, roughly oblong leaves are held semi-erect and have a distinct petiole. It is quite a variable plant with several recognised growth forms, some of which form a short stem. As in all sundews, the leaves are covered in stalked glands that secrete sticky mucilage. These attract, trap, and digest arthropod prey, obtaining nutrients that supplement intake from the substrate in which the plant grows. D. capensis has dramatically mobile leaves that curl around captured prey, preventing its escape and facilitating digestion.
First recorded in the late 17th century, D. capensis was one of the five Drosera species included in the first edition of Carl Linnaeus' Species plantarum. A relatively large, 'showy' species that flowers readily and is considered very easy to grow, it was cultivated in Europe as a curiosity from the mid-18th century and is now one of the most widely-grown sundews. It has also been extensively studied, including as a potential source of bioactive compounds of pharmacological interest, and was the first sundew to undergo whole-genome sequencing. Although often uncommon and localised in its native range, it has become naturalised in several countries following deliberate introductions, and is listed as an invasive species in New Zealand. (Full article...)
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The gold-of-pleasure or false flax resembles flax, and its seeds are practically inseparable from the flax seed.
Selection against the weed may occur by killing a young or adult weed, by separating its seeds from those of the crop by winnowing, or both. The process has operated since Neolithic times, creating secondary crops such as rye and oats through mimicry of cereals such as wheat. (Full article...)
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Portrait by Joseph Hornung, 1839
Augustin Pyramus (or Pyrame) de Candolle (UK: /kænˈdɒl/, US: /kɒ̃ˈdɔːl/, French:[kɑ̃dɔl]; 4 February 1778 – 9 September 1841) was a Swissbotanist. René Louiche Desfontaines launched de Candolle's botanical career by recommending him at a herbarium. Within a couple of years de Candolle had established a new genus, and he went on to document hundreds of plant families and create a new natural plant classification system. Although de Candolle's main focus was botany, he also contributed to related fields such as phytogeography, agronomy, paleontology, medical botany, and economic botany.
De Candolle originated the idea of "Nature's war", which influenced Charles Darwin and the principle of natural selection. De Candolle recognized that multiple species may develop similar characteristics that did not appear in a common evolutionary ancestor; a phenomenon now known as convergent evolution. During his work with plants, de Candolle noticed that plant leaf movements follow a near-24-hour cycle in constant light, suggesting that an internal biological clock exists. Though many scientists doubted de Candolle's findings, experiments over a century later demonstrated that "the internal biological clock" indeed exists. (Full article...)
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Hypericum russeggeri is a species of flowering plant in the St John's wort family Hypericaceae. The plant is a small shrub with many branches that spread across the ground, and it has many small flowers with pale yellow petals. It is found only among calcareous rocks along the coast and in the foothills of the Nur Mountains of eastern Turkey and northern Syria. While H. russeggeri has an array of phytochemicals present in its flowering structures and leaves, these are found in lower concentrations than other species of Hypericum. The species was first described in 1842 as Triadenia russeggeri, and it has been placed into various defunct genera including Elodea and Adenotrias. It is now known as Hypericum russeggeri and is the type species of Hypericum section Adenotrias, a small section that also includes H. aegypticum and H. aciferum. (Full article...)
The name Fritillaria is thought to refer to the checkered pattern of F. meleagris, resembling a box in which dice were carried. Fritillaries are commercially important in horticulture as ornamental garden plants and also in traditional Chinese medicine, which is also endangering some species. Fritillaria flowers have been popular subjects for artists to depict and as emblems of regions and organizations. (Full article...)
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Orto botanico di Pisa, the first university botanic garden in Europe, established in 1544 under botanist Luca Ghini, operated by the University of Pisa. It was relocated in 1563 and again in 1591.
A botanical garden or botanic garden is a garden with a documented collection of living plants for the purpose of scientific research, conservation, display, and education. It is their mandate as a botanical garden that plants are labelled with their botanical names. It may contain specialist plant collections such as cacti and other succulent plants, herb gardens, plants from particular parts of the world, and so on; there may be glasshouses or shadehouses, again with special collections such as tropicalplants, alpine plants, or other exotic plants that are not native to that region.
Most are at least partly open to the public, and may offer guided tours, public programming such as workshops, courses, educational displays, art exhibitions, book rooms, open-air theatrical and musical performances, and other entertainment. (Full article...)
A pine is any conifer in the genusPinus (/ˈpaɪ.nəs/) of the family Pinaceae. Pinus is the sole genus in the subfamilyPinoideae. The species are evergreen trees or shrubs with their leaves in bunches, usually of 2 to 5 needles. The seeds are carried on woody cones, with two seeds to each cone scale.
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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Eriophorum angustifolium, commonly known as common cottongrass or common cottonsedge, is a species of flowering plant in the sedge family, Cyperaceae. Native to North America, North Asia, and Europe, it grows on peat or acidic soils, in open wetland, heath or moorland. It begins to flower in April or May and, after fertilisation in early summer, the small, unremarkable brown and green flowers develop distinctive white bristle-like seed-heads that resemble tufts of cotton; combined with its ecological suitability to bog, these characteristics give rise to the plant's alternative name, bog cotton.
James Kirkham Ramsbottom (11 October 1891 – 9 February 1925) was an English botanist. He became interested in the field after he was recommended to pursue an outdoor career for his health. After a short period at the Chelsea Physic Garden, Ramsbottom studied at the RHS Garden Wisley. Coming first in their diploma examinations, Ramsbottom became a research student at the Royal Horticultural Society (RHS) in 1913. He studied leaf blotch disease in irises and became assistant editor of Gardeners' Magazine.
In March 1916, Ramsbottom was appointed to lead a study into a mysterious disease, known as "rootless disease", that was affecting daffodil (Narcissus) bulbs and threatened the destruction of the nascent daffodil-growing industry. The disease had been known for around 30 years, but its cause was not certain, although a number of pests and fungi were suspected. By April 1917 Ramsbottom was able to prove the disease was caused by an infestation of the Ditylenchus dipsaci nematode and developed a treatment involving dipping affected bulbs in hot water. The treatment saved the daffodil-growing industry and remains the basis for modern-day treatment of the disease. Ramsbottom continued to work on the treatment and was invited to lecture in the United States. He died in New York by either falling or jumping from a 19th-storey window in the Hotel McAlpin. (Full article...)
Durio graveolens, sometimes called the red-fleshed durian, orange-fleshed durian, or yellow durian, is a species of tree in the family Malvaceae. It is one of six species of durian named by Italian naturalist Odoardo Beccari. The specific epithetgraveolens ('strong smelling' or 'rank') is due to the odor. Although most species of Durio (most notably Durio dulcis) have a strong scent, the red-fleshed type of D. graveolens has a mild scent. It is native to Southeast Asia.
D. graveolens is an edible durian, perhaps the most popular 'wild' species of durian, and it is sold commercially regionally. (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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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...)
... 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 the name of Diaphoretickes, a group containing a huge diversity of organisms including plants and kelps, is derived from a Greek word meaning diverse?
... that Erna Meyer urged the Jewish immigrant readers of How to Cook in Palestine to try olives and eggplants, but doubted their ability to eat spicy food like the "native population"?
The following are images from various plant-related articles on Wikipedia.
Image 1Structure 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 5A banded tube from the Late Silurian/Early Devonian. The bands are difficult to see on this specimen, as an opaque carbonaceous coating conceals much of the tube. Bands are just visible in places on the left half of the image. Scale bar: 20 μm (from Evolutionary history of plants)
Image 7The 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 10A nineteenth-century illustration showing the morphology of the roots, stems, leaves and flowers of the rice plant Oryza sativa (from Botany)
Image 11A 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 13The food we eat comes directly or indirectly from plants such as rice. (from Botany)
Image 14Micropropagation of transgenic plants (from Botany)
Image 15The 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 16Transverse section of a fossil stem of the Devonian vascular plant Rhynia gwynne-vaughani (from Botany)
Image 17Leaf lamina. The megaphyllous leaf architecture arose multiple times in different plant lineages (from Evolutionary history of plants)
Image 19Five of the key areas of study within plant physiology (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 21Paper chromatography of some spinach leaf extract shows the various pigments present in their chloroplasts: yellowish xanthophylls, greenish chlorophylls a and b. (from Botany)
Image 22Structure of a plant cell (from Plant cell)
Image 25This is an electron micrograph of the epidermal cells of a Brassica chinensis leaf. The stomates are also visible. (from Plant cell)
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 30Echeveria glauca in a Connecticut greenhouse. Botany uses Latin names for identification; here, the specific name glauca means blue. (from Botany)
Image 31A botanist preparing a plant specimen for mounting in the herbarium (from Botany)
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