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Persoonia linearis, commonly known as the narrow-leaved geebung, is a shrub native to New South Wales and Victoria in eastern Australia. It reaches 3 m (9.8 ft), or occasionally 5 m (16 ft), in height and has thick, dark grey papery bark. The leaves are, as the species name suggests, more or less linear in shape, and are up to 9 cm (3.5 in) long, and 0.1 to 0.7 cm (0.039 to 0.276 in) wide. The small yellow flowers appear in summer, autumn and early winter (December to July), followed by small green fleshy fruit known as drupes. Within the genus Persoonia, it is a member of the Lanceolata group of 58 closely related species. P. linearis interbreeds with several other species where they grow together.
Two subspecies—P.t.terminalis and P.t.recurva—are recognised; both are found on well-drained acidic soils in sclerophyll forests, and P.t.terminalis is also found on granite outcrops. Although similar in appearance, they differ in leaf length and curvature. Both have a restricted range, with P.t.terminalis found in an area of under 100 square kilometres (39 square miles; 25,000 acres). (Full article...)
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...)
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...)
Persoonia levis, commonly known as the broad-leaved geebung, is a shrub native to New South Wales and Victoria in eastern Australia. It reaches 5 m (16 ft) in height and has dark grey papery bark and bright green asymmetrical sickle-shaped leaves up to 14 cm (5.5 in) long and 8 cm (3.2 in) wide. The small yellow flowers appear in summer and autumn (December to April), followed by small green fleshy fruit, which are classified as drupes. Within the genus Persoonia, it is a member of the Lanceolata group of 58 closely related species. P. levis interbreeds with several other species where they grow together.
Barbara McClintock (June 16, 1902 – September 2, 1992) was an American scientist and cytogeneticist who was awarded the 1983 Nobel Prize in Physiology or Medicine. McClintock received her PhD in botany from Cornell University in 1927. There she started her career as the leader of the development of maize cytogenetics, the focus of her research for the rest of her life. From the late 1920s, McClintock studied chromosomes and how they change during reproduction in maize. She developed the technique for visualizing maize chromosomes and used microscopic analysis to demonstrate many fundamental genetic ideas. One of those ideas was the notion of genetic recombination by crossing-over during meiosis—a mechanism by which chromosomes exchange information. She produced the first genetic map for maize, linking regions of the chromosome to physical traits. She demonstrated the role of the telomere and centromere, regions of the chromosome that are important in the conservation of genetic information. She was recognized as among the best in the field, awarded prestigious fellowships, and elected a member of the National Academy of Sciences in 1944.
During the 1940s and 1950s, McClintock discovered transposition and used it to demonstrate that genes are responsible for turning physical characteristics on and off. She developed theories to explain the suppression and expression of genetic information from one generation of maize plants to the next. Due to skepticism of her research and its implications, she stopped publishing her data in 1953. (Full article...)
The flowers hold profuse amounts of nectar and are pollinated by honeyeaters. Although L. formosa is uncommon in cultivation, it is straightforward to grow in soils with good drainage and a partly shaded to sunny aspect. It is readily propagated by seed. Unlike all other members of the genus Lambertia, L. formosa is greatly resistant to the soil pathogen Phytophthora cinnamomi. (Full article...)
Insects such as bees, wasps and even ants can pollinate the flowers. B. petiolaris is nonlignotuberous, meaning it regenerates by seed after bushfire. B. petiolaris adapts readily to cultivation, growing in well-drained sandy soils in sunny locations. It is suitable for rockeries and as a groundcover. (Full article...)
Banksia caleyi, commonly known as Caley's banksia or red lantern banksia, is a species of woody shrub of the family Proteaceae native to Western Australia. It generally grows as a dense shrub up to 2 m (7 ft) tall, has serrated leaves and red, pendent (hanging) inflorescences which are generally hidden in the foliage. First described by Scottish naturalist Robert Brown in 1830, Banksia caleyi was named in honour of the English botanist George Caley. No subspecies are recognised. It is one of three or four related species with hanging inflorescences, which is an unusual feature within the genus.
Telopea truncata, commonly known as the Tasmanian waratah, is a plant in the family Proteaceae. It is endemic to Tasmania where it is found on moist acidic soils at altitudes of 600 to 1200 m (2000–4000 ft). Telopea truncata is a component of alpine eucalypt forest, rainforest and scrub communities. It grows as a multistemmed shrub to a height of 3 metres (10 ft), or occasionally as a small tree to 10 m (35 ft) high, with red flower heads, known as inflorescences, appearing over the Tasmanian summer (November to February) and bearing 10 to 35 individual flowers. Yellow-flowered forms are occasionally seen, but do not form a population distinct from the rest of the species.
Collected by French botanist Jacques Labillardière in 1792–93, Telopea truncata was first scientifically described in 1805. Genetic analysis revealed that the Tasmanian waratah is the most distinctive of the five waratah species. It can be cultivated in temperate climates, requiring soils with good drainage and ample moisture in part-shaded or sunny positions. Several commercially available cultivars that are hybrids of T. truncata with the New South Wales waratah (T. speciosissima) and Gippsland waratah (T. oreades) have been developed. (Full article...)
Alloxylon flammeum, commonly known as the Queensland tree waratah or red silky oak, is a medium-sized tree of the family Proteaceae found in the Queensland tropical rain forests of northeastern Australia. It has shiny green elliptical leaves up to 18 cm (7.1 in) long, and prominent orange-red inflorescences that appear from August to October, followed by rectangular woody seed pods that ripen in February and March. Juvenile plants have large (up to 25 cm (9.8 in) long) deeply lobed pinnate leaves. Previously known as Oreocallis wickhamii, the initial specimen turned out to be a different species to the one cultivated and hence a new scientific name was required. Described formally by Peter Weston and Mike Crisp in 1991, A. flammeum was designated the type species of the genus Alloxylon. This genus contains the four species previously classified in Oreocallis that are found in Australasia.
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...)
Banksia verticillata, commonly known as granite banksia or Albany banksia, is a species of shrub or (rarely) tree of the genus Banksia in the family Proteaceae. It is native to the southwest of Western Australia and can reach up to 3 m (10 ft) in height. It can grow taller to 5 m (16 ft) in sheltered areas, and much smaller in more exposed areas. This species has elliptic green leaves and large, bright golden yellow inflorescences or flower spikes, appearing in summer and autumn. The New Holland honeyeater (Phylidonyris novaehollandiae) is the most prominent pollinator, although several other species of honeyeater, as well as bees, visit the flower spikes.
A declared vulnerable species, it occurs in two disjunct populations on granite outcrops along the south coast of Western Australia, with the main population near Albany and a smaller population near Walpole, and is threatened by dieback (Phytophthora cinnamomi) and aerial canker (Zythiostroma). B. verticillata is killed by bushfire and new plants regenerate from seed afterwards. Populations take over a decade to produce seed and fire intervals of greater than twenty years are needed to allow the canopy seed bank to accumulate. (Full article...)
As a cereal grain, domesticated rice is the most widely consumed staple food for over half of the world's human population, especially in Asia and Africa. It is the agricultural commodity with the third-highest worldwide production, after sugarcane and maize. Since sizable portions of sugarcane and maize crops are used for purposes other than human consumption, rice is the most important food crop with regard to human nutrition and caloric intake, providing more than one-fifth of the calories consumed worldwide by humans. There are many varieties of rice and culinary preferences tend to vary regionally. (Full article...)
Coconuts falling from their trees and striking individuals can cause serious injury to the back, neck, shoulders and head, and are occasionally fatal.
Following a 1984 study on "Injuries Due to Falling Coconuts", exaggerated claims spread concerning the number of deaths by falling coconuts. Falling coconuts, according to urban legend, kill a few people a year. This legend gained momentum after the 2002 work of a noted expert on shark attacks was characterized as saying that falling coconuts kill 150 people each year worldwide. This statistic has often been contrasted with the number of shark-caused deaths per year, which is around five. (Full article...)
The Botanical Magazine, 1845 title page
The Botanical Magazine; or Flower-Garden Displayed, is an illustrated publication which began in 1787. The longest running botanical magazine, it is widely referred to by the subsequent name Curtis's Botanical Magazine.
Each of the issues contains a description, in formal yet accessible language, and is renowned for featuring the work of two centuries of botanical illustrators. Many plants received their first publication on the pages, and the description given was enhanced by the keenly detailed illustrations. (Full article...)
Pollination by insects is called entomophily. Entomophily is a form of plant pollination whereby pollen is distributed by insects, particularly bees, Lepidoptera (butterflies and moths), flies and beetles. Honey bees pollinate many plant species that are not native to their natural habitat but are often inefficient pollinators of such plants; if they are visiting ten different species of flower, only a tenth of the pollen they carry may be the right species. Other bees tend to favor one species at a time, therefore do most of the actual pollination. (Full article...)
Utricularia vulgaris illustration from Jakob Sturm's "Deutschlands Flora in Abbildungen", Stuttgart (1796)
Utricularia, commonly and collectively called the bladderworts, is a genus of carnivorous plants consisting of approximately 233 species (precise counts differ based on classification opinions; a 2001 publication lists 215 species). They occur in fresh water and wet soil as terrestrial or aquatic species across every continent except Antarctica. Utricularia are cultivated for their flowers, which are often compared with those of snapdragons and orchids, especially amongst carnivorous plant enthusiasts.
All Utricularia are carnivorous and capture small organisms by means of bladder-like traps. Terrestrial species tend to have tiny traps that feed on minute prey such as protozoa and rotifers swimming in water-saturated soil. The traps can range in size from 0.02 to 1.2 cm (0.008 to 0.5 in). Aquatic species, such as U. vulgaris (common bladderwort), possess bladders that are usually larger and can feed on more substantial prey such as water fleas (Daphnia), nematodes and even fish fry, mosquitolarvae and young tadpoles. Despite their small size, the traps are extremely sophisticated. In the active traps of the aquatic species, prey brush against trigger hairs connected to the trapdoor. The bladder, when "set", is under negative pressure in relation to its environment so that when the trapdoor is mechanically triggered, the prey, along with the water surrounding it, is sucked into the bladder. Once the bladder is full of water, the door closes again, the whole process taking only ten to fifteen milliseconds. (Full article...)
Ethnobotany is the study of a region's plants and their practical uses through the traditional knowledge of a local culture and people. An ethnobotanist thus strives to document the local customs involving the practical uses of local flora for many aspects of life, such as plants as medicines, foods, intoxicants and clothing. Richard Evans Schultes, often referred to as the "father of ethnobotany", explained the discipline in this way:
Ethnobotany simply means ... investigating plants used by societies in various parts of the world.
Since the time of Schultes, the field of ethnobotany has grown from simply acquiring ethnobotanical knowledge to that of applying it to a modern society, primarily in the form of pharmaceuticals. Intellectual property rights and benefit-sharing arrangements are important issues in ethnobotany. (Full article...)
Redcurrants, a type of berry derived from a simple (one-carpel) inferior ovary
In botany, a berry is a fleshy fruit without a stone (pit) produced from a single flower containing one ovary. Berries so defined include grapes, currants, and tomatoes, as well as cucumbers, eggplants (aubergines) 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 peppers, with air rather than pulp around their seeds.
The toxins in poisonous plants affect herbivores, and deter them from consuming the plants. Plants cannot move to escape their predators, so they must have other means of protecting themselves from herbivorous animals. Some plants have physical defenses such as thorns, spines and prickles, but by far the most common type of protection is chemical. (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 and endangering over 1000 more. (Full article...)
The Meilland Family is a multi-generational family of French rose breeders. The family's first rosarian was gardener, Joseph Rambaux, who first started breeding roses in 1850 in Lyon. He is best known for developing the Polyantha'Perle d'Or'. His wife, Claudine and son-in-law, Francois Dubreuil, took over the nursery after Rambaux died in 1878. Dubreuil became a successful rose breeder and grower. In 1900, Dubreuil hired sixteen year old, Antoine Meilland, as a gardening assistant, where he met Dubreuil's daughter, Claudia. Antoine and Claudia married in 1909 and their son, Francis was born in 1912. The couple took over Dubreuil's nursery after his death in 1916.
After World War I, Antoine and Claudia bought property in Tassin-la-Demi-Lune, near Lyon and started a new nursery. Their son, Francis, married Marie-Louise (Louisette) Paolino, daughter of an Italian rose breeder in 1939. Francis expanded the rose business over time into a large, international company, and became the most famous and prolific rose breeder in the family. His legendary 'Peace' rose, brought the family international attention and great commercial success when it was introduced after World War II. The Meilland family merged their business with Francisque Richardier in 1946, so that Francis Meilland could focus solely on breeding roses. After Francis's early death in 1958, Louisette continued to breed roses, introducing many awarding winning new varieties. The new company, Meilland-Richardier grew into Meilland International (AKA House of Meilland), and is located in Le Luc en Provence, France. Francis and Louisette's children, Alain and Michele, are both successful rose breeders and continue to manage the company. (Full article...)
Polemonium reptans is a flowering plant in the genus Polemonium, native to eastern North America. Common names include Abscess Root, Creeping or Spreading Jacob's Ladder, False Jacob's Ladder, American Greek Valerian, Blue bells, Stairway to Heaven, and Sweatroot.
The earliest historical records of herbs are found from the Sumerian civilization, where hundreds of medicinal plants including opium are listed on clay tablets, c. 3000 BC. The Ebers Papyrus from ancient Egypt, c. 1550 BC, describes over 850 plant medicines. The Greek physician Dioscorides, who worked in the Roman army, documented over 1000 recipes for medicines using over 600 medicinal plants in De materia medica, c. 60 AD; this formed the basis of pharmacopoeias for some 1500 years. Drug research sometimes makes use of ethnobotany to search for pharmacologically active substances, and this approach has yielded hundreds of useful compounds. These include the common drugs aspirin, digoxin, quinine, and opium. The compounds found in plants are of many kinds, but most are in four major biochemical classes: alkaloids, glycosides, polyphenols, and terpenes. (Full article...)
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...)
University of Minnesota awarded Pepin Heights Orchards exclusive marketing rights to grow and sell the 'Minneiska' apple. They then in turn developed a cooperative of certain selected farm growers and sold rights to these members to produce the apple. It was exclusive at first to the state of Minnesota and later membership was expanded to certain qualifying farmers, mostly to growers of the northern parts of the United States. The concept of exclusive control of a variety of fruit was new then in United States customs and drew criticism that led to lawsuits. (Full article...)
Richard Buxton (15 January 1786 – 2 January 1865) was a British shoemaker and amateur botanist. Born in Prestwich, Lancashire, to a family who lived in humble circumstances, he taught himself to read, and learned the basic principles of botany. Although living as a pauper for most of his life, in 1849 he published A Botanical Guide to the Flowering Plants, Ferns, Mosses and Algæ, Found Indigenous Within Sixteen Miles of Manchester, which became one of the standard texts on the flora then commonly found in the Manchester area. According to his obituary in the Journal of Botany, British and Foreign, Buxton was one of "nature's gentlemen" and "his true and correct pronunciation of scientific terms have caused many who heard him to believe he was an accomplished classical scholar". He was acknowledged by the geologist Edward William Binney as "the most profound thinker of his class". (Full article...)
Roystonea regia, commonly known as the Cuban royal palm or Florida royal palm, is a species of palm that is native to Mexico, parts of Central America and the Caribbean, and southern Florida. A large and attractive palm, it has been planted throughout the tropics and subtropics as an ornamental tree. Although it is sometimes called R. elata, the conserved nameR. regia is now the correct name for the species. The royal palm reaches heights from 50 to over 80 feet tall. Populations in Cuba and Florida were long seen as separate species, but are now considered a single species.
Widely planted as an ornamental, R. regia is also used for thatch, construction timber, and in some forms of so-called traditional medicine, although there is currently no valid scientific evidence to support the efficacy or use of any palm species for medicinal purposes. The fruit is eaten by birds and bats (which disperse the seeds) and fed to livestock. Its flowers are visited by birds and bats, and it serves as a roosting site and food source for a variety of animals. Roystonea regia is the national tree of Cuba, and has a religious role both in Santería and Christianity, where it is used in Palm Sunday observances. (Full article...)
The species was originally described as a pitcher plant with close affinities to extant members of the familySarraceniaceae. This would make it the earliest known carnivorous plant and the only known fossil record of Sarraceniaceae, or the New World pitcher plant family. Archaeamphora is also one of the three oldest known genera of angiosperms (flowering plants). Li (2005) wrote that "the existence of a so highly derived Angiosperm in the Early Cretaceous suggests that Angiosperms should have originated much earlier, maybe back to 280 mya as the molecular clock studies suggested". (Full article...)
The book is organised chronologically and mainly describes the voyage from England to Tahiti, the time spent there, and the encounters with New Zealand and Australia. It contains Parkinson's vocabularies of several Pacific languages and also many plant names given by Daniel Solander, but most of these have not been accepted as botanical names. The book is illustrated by engravings based on Sydney Parkinson's drawings. It has been praised for its authenticity but criticised by botanists for the low quality of the botanical content. (Full article...)
Ripe honeynut squash
Honeynut squash is a winter squash cultivar bred from butternut and buttercup squash. It has a similar shape and flavor to butternut squash but averages about half the size and is significantly sweeter. It has dark tan to orange skin and orange fleshy pulp. When ripe, it turns from green to a deep orange and becomes sweeter and richer. It has two to three times more beta-carotene than butternut squash. Although technically a fruit, honeynut squash is used as a vegetable that can be roasted, sautéed, puréed, added to soups, stews, and braises, and is suitably sweet for desserts.
The squash was first developed in the 1980s by Richard W. Robinson, a professor emeritus at Cornell University. Robinson cross-bred two species of Cucurbita, though the original product never reached markets. Around 2006, Cornell professor and plant breeder Michael Mazourek developed a cultivar that successfully entered USA national markets in 2015. He received assistance in developing the product from Dan Barber, chef and owner of Blue Hill and Blue Hill at Stone Barns in New York. The pair are currently developing an improved product, known as 898, expected to have an improved shelf life. (Full article...)
Title page of the 1776 quarto edition of Characteres generum plantarum
Characteres generum plantarum (complete title Characteres generum plantarum, quas in Itinere ad Insulas Maris Australis, Collegerunt, Descripserunt, Delinearunt, annis MDCCLXXII-MDCCLXXV Joannes Reinoldus Forster et Georgius Forster, "Characteristics of the types of plants collected, described, and delineated during a voyage to islands of the South Seas, in the years 1772–1775 by Johann Reinhold Forster and Georg Forster") is a 1775/1776 book by Johann Reinhold Forster and Georg Forster about the botanical discoveries they made during the second voyage of James Cook.
The book contains 78 plates, the majority of which depict dissections of flowers at natural size. The book introduced 94 binomial names from 75 genera, of which 43 are still the accepted names today. Many plant genera were named after friends or patrons of the Forsters. The book was published in a folio and a quarto edition and translated into German in 1779. It is an important book as the earliest publication of names and descriptions of the native species of New Zealand. (Full article...)
Simarouba amara has been studied extensively by scientists in an attempt to understand the tree and also to gain a better understanding of the ecology of the rainforest in general. Many of these studies were conducted on Barro Colorado Island in Panama or at La Selva Biological Station in Costa Rica. Of particular interest is how it competes with other species and with individuals of the same species at different stages in its life cycle. The seedlings are normally limited by the amount of light and nutrients found where they are growing and the saplings are considered relatively light demanding compared to other species. Young individuals are more likely to survive when they grow further away from their parents and when there are few other individuals growing near to them, which may be due to them being able to escape diseases. Plant physiologists have investigated how the leaves of the tree differ depending on their location in the forest canopy finding they are thicker in the canopy and thinner in the understory. They have also measured how the water potential of their leaves changes and when their stomata open and close during the day; the findings suggest that rather than closing their stomata to control water loss, it is controlled by the leaf area instead. Population geneticists have examined the way in which its genes vary, at both the local scale and across its range using microsatellites. It is genetically diverse, indicating gene flow occurs between populations and seeds can be dispersed up to 1 km. The leaves of S. amara are eaten by several species of caterpillar, particularly those in the genus Atteva. Several species of termite and ants live on or around the tree and lianas and epiphytes grow on the tree. (Full article...)
In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, including only woody plants with secondary growth, plants that are usable as lumber or plants above a specified height. In wider definitions, the taller palms, tree ferns, bananas, and bamboos are also trees. Trees are not a taxonomic group but include a variety of plant species that have independently evolved a trunk and branches as a way to tower above other plants to compete for sunlight. The majority of tree species are angiosperms or hardwoods; of the rest, many are gymnosperms or softwoods. Trees tend to be long-lived, some reaching several thousand years old. Trees have been in existence for 370 million years. It is estimated that there are some three trillion mature trees in the world.
A tree typically has many secondary branches supported clear of the ground by the trunk. This trunk typically contains woody tissue for strength, and vascular tissue to carry materials from one part of the tree to another. For most trees it is surrounded by a layer of bark which serves as a protective barrier. Below the ground, the roots branch and spread out widely; they serve to anchor the tree and extract moisture and nutrients from the soil. Above ground, the branches divide into smaller branches and shoots. The shoots typically bear leaves, which capture light energy and convert it into sugars by photosynthesis, providing the food for the tree's growth and development. (Full article...)
Dracophyllum traversii, commonly known as mountain neinei, grass tree, and pineapple tree is a species of flowering plant in the heath family Ericaceae. It is a deciduous tree (or, in some cases, a shrub) endemic to New Zealand. It reaches a height of 0.2–13 m (0.66–42.65 ft) and has leaves which form tufts at the end of its branches. It has a lifespan 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...)
Image 22The 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 25The 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 311 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 36A 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 37Thale cress, Arabidopsis thaliana, the first plant to have its genome sequenced, remains the most important model organism. (from Botany)