There are about 380,000 known
species of plants, of which the majority, some 260,000,
produce seeds. They range in size from single cells to the tallest
trees. Green plants provide a substantial proportion of the world's molecular oxygen; the sugars they create supply the energy for most of Earth's
ecosystems and other
organisms, including animals, either
consume plants directly or rely on organisms which do so. (Full article...)
These are
featured articles, which represent some of the best content on English Wikipedia.
Image 1
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 grossa is a species of
shrub in the
familyProteaceae and is
endemic to
Southwest Australia. It is one of fourteen species of
banksia of the series Abietinae, all of which bear predominantly cylindrical or oval
inflorescences. Collected in 1965, it was first formally described in 1981 by
Alex George. Its thick leaves and large seeds distinguish it from other members of the Abietinae, and are the basis of its species name.
Found in sand or sand over
laterite among
heath between
Eneabba and
Badgingarra in Western Australia, the species grows as a many-stemmed shrub to 1 m (3.3 ft) high with narrow leaves and oval brownish flower spikes up to 10 cm (4 in) high, composed of hundreds of individual flowers. Flowering occurs throughout the cooler months of March to September. Flower spikes develop woody
follicles which bear the seeds. After
bushfire, Banksia grossa regenerates from its woody
lignotuber; bushfires also stimulate the release of seeds, which germinate after disturbance. Visitors to (and likely
pollinators of) inflorescences include insects and a nocturnal mammal, the
white-tailed dunnart. (Full article...)
Image 3
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...)
Image 4
Several plants in cultivation
Drosera regia, commonly known as the king sundew, is a
carnivorous plant in the sundew genus Drosera that is
endemic to a single valley in
South Africa. The genus name Drosera comes from the
Greek word droseros, meaning "dew-covered". The
specific epithetregia is derived from the
Latin for "royal", a reference to the "striking appearance" of the species. Individual leaves can reach 70 cm (28 in) in length. It has many unusual
relict characteristics not found in most other Drosera species, including woody
rhizomes,
operculatepollen, and the lack of
circinate vernation in
scape growth. All of these factors, combined with
molecular data from
phylogenetic analysis, contribute to the evidence that D. regia possesses some of the most ancient characteristics within the genus. Some of these are shared with the related
Venus flytrap (Dionaea muscipula), which suggests a close evolutionary relationship.
The
tentacle-covered leaves can capture large prey, such as beetles, moths, and butterflies. The tentacles of all Drosera species have special stalked glands on the leaf's upper surface that produce a sticky
mucilage. The leaves are considered active
flypaper traps that respond to captured prey by bending to surround it. In its native
fynbos habitat, the plants compete for space with native marsh grasses and low
evergreenshrubs. Of the two known populations of D. regia, the higher elevation site appears to be overgrown and is essentially
extirpated. The lower elevation site is estimated to have about 50 mature plants, making it the most endangered Drosera species, since it is threatened with extinction in the wild. It is often cultivated by carnivorous plant enthusiasts, and a single
cultivar has been registered. (Full article...)
Image 5
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...)
Banksia menziesii, commonly known as firewood banksia, is a
species of flowering plant in the genus Banksia. It is a gnarled tree up to 10 m (33 ft) tall, or a lower spreading 1–3 m (3.3–9.8 ft) shrub in the more northern parts of its range. The serrated leaves are dull green with new growth a paler grey green. The prominent autumn and winter
inflorescences are often two-coloured red or pink and yellow, and their colour has given rise to more unusual
common names such as port wine banksia and strawberry banksia. Yellow blooms are rarely seen.
First described by the botanist
Robert Brown in the early 19th century, no separate
varieties of Banksia menziesii are recognised. It is found in Western Australia, from the
Perth (32° S) region north to the
Murchison River (27° S), and generally grows on sandy soils, in
scrubland or low
woodland. Banksia menziesii provides food for a wide array of
invertebrate and
vertebrate animals; birds and in particular
honeyeaters are prominent visitors. A relatively hardy plant, Banksia menziesii is commonly seen in gardens,
nature strips and parks in Australian urban areas with
Mediterranean climates, but its sensitivity to dieback from the soil-borne water mould Phytophthora cinnamomi makes it short-lived in places with humid summers, such as Sydney. Banksia menziesii is widely used in the
cut flower industry both in Australia and overseas. (Full article...)
Johann George Adam Forster, also known as Georg Forster (German pronunciation:[ˈɡeːɔʁkˈfɔʁstɐ], 27 November 1754 – 10 January 1794), was a German
geographer,
naturalist,
ethnologist,
travel writer, journalist and revolutionary. At an early age, he accompanied his father,
Johann Reinhold Forster, on several scientific expeditions, including
James Cook's
second voyage to the
Pacific. His report of that journey, A Voyage Round the World, contributed significantly to the ethnology of the people of
Polynesia and remains a respected work. As a result of the report, Forster, who was admitted to the
Royal Society at the early age of twenty-two, came to be considered one of the founders of modern scientific travel literature.
After returning to continental Europe, Forster turned toward academia. He taught natural history at the
Collegium Carolinum in the
Ottoneum,
Kassel (1778–84), and later at the
Academy of Vilna (Vilnius University) (1784–87). In 1788, he became
head librarian at the
University of Mainz. Most of his scientific work during this time consisted of essays on
botany and ethnology, but he also prefaced and translated many books about travel and exploration, including a German translation of Cook's diaries. (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...)
Image 9
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...)
Image 10
Epacris impressa, also known as common heath, is a species of plant in the heath family
Ericaceae. It is native to south-eastern Australia (the states of
Victoria,
Tasmania,
South Australia and
New South Wales). French botanist
Jacques Labillardière collected the species in 1793 and
described it in 1805. Four forms have been identified, but no subspecies are recognised. Growing in heathland, shrubland or open forest, it is generally a small shrub around 0.5 to 1 m (1 ft 8 in to 3 ft 3 in) tall, with small stiff leaves. The red, pink or white tube-like flowers appear from late autumn to early spring.
Honeyeater birds, particularly the
eastern spinebill, feed upon the nectar of the flowers. It regenerates after
bushfire by seed or by
resprouting.
A highly regarded garden plant, the common heath was first cultivated in England in 1825; over seventy named
cultivars have been developed, most of which have now vanished. A pink-flowered form, often referred to as "pink heath", is the
floral emblem of the state of
Victoria. Epacris impressa has proven a difficult plant to
propagate reliably, which has limited its use in horticulture and revegetation. It grows best in well-drained but moist soil in a semishaded position. (Full article...)
Its aromatic, "
labrusca" flavor is similar to that of Concord, but mellowed by the mild, sweet taste from Thompson Seedless. Thomcord grows well in hot, dry climates, ripens between late July and mid-August, and tolerates
powdery mildew. It is a productive variety, yielding an average of 15.1 kg (33 lb) of grapes per vine, but has produced as much as 30 to 32 kg (66 to 71 lb) per vine in grower trials. The berries weigh between 2.72 and 3.38 g (0.096 and 0.119 oz) and have a medium-thick, blue-black skin that adheres to the fruit, unlike Concord, which has a thick skin that can slip off the pulp easily. The
aborted seeds in the fruit body are relatively small, but larger than those in Thompson Seedless. (Full article...)
Image 12
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...)
Image 13
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. These other gourds are used as utensils or vessels, and 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...)
Banksia spinulosa, the hairpin banksia, is a species of woody
shrub, of the genus Banksia in the family
Proteaceae, native to eastern
Australia. Widely distributed, it is found as an
understorey plant in open dry forest or
heathland from
Victoria to northern
Queensland, generally on sandstone though sometimes also clay soils. It generally grows as a small shrub to 2 metres (7 ft) in height, though can be a straggly tree to 6 metres (20 ft). It has long narrow leaves with
inflorescences which can vary considerably in coloration; while the spikes are gold or less commonly yellowish, the emergent styles may be a wide range of colours – from black, purple, red, orange or yellow.
Banksia spinulosa was named by
James Edward Smith in England in 1793, after being collected by
John White, most likely in 1792. He gave it the common name prickly-leaved banksia, though this has fallen out of use. With four currently recognised varieties, the species has had a complicated
taxonomic history, with two varieties initially described as separate species in the early 19th century. A fourth, from the
New England region, has only recently been described. However, there has been disagreement whether one, var. cunninghamii, is distinct enough to once again have specific status. The pre-eminent authority on Banksia,
Alex George, concedes there is still more work to be done on the Banksia spinulosa complex. (Full article...)
Banksia aemula, commonly known as the wallum banksia, is a
shrub of the family
Proteaceae. Found from
Bundaberg south to
Sydney on the Australian east coast, it is encountered as a shrub or a tree to 8 m (26 ft) in coastal
heath on deep sandy soil, known as
Wallum. It has wrinkled orange bark and shiny green serrated leaves, with green-yellow flower spikes, known as
inflorescences, appearing in autumn. The flower spikes turn grey as they age and large grey
follicles appear. Banksia aemula resprouts from its woody base, known as a
lignotuber, after
bushfires.
First described by the botanist
Robert Brown in the early 19th century, it derives its specific name "similar" from its resemblance to the closely related B. serrata. No
varieties are recognised. It was known for many years in New South Wales as B. serratifolia, contrasting with the use of B. aemula elsewhere. However, the former name, originally coined by
Richard Anthony Salisbury, proved invalid, and Banksia aemula has been universally adopted as the correct
scientific name since 1981. A wide array of mammals, birds, and invertebrates visit the inflorescences and are instrumental in pollination;
honeyeaters are particularly prominent visitors. Grown as a garden plant, it is less commonly seen in horticulture than its close relative B. serrata. (Full article...)
Vegetative reproduction (also known as vegetative propagation, vegetative multiplication or cloning) is a form of
asexual reproduction occurring in plants in which a new plant grows from a fragment or
cutting of the parent plant or specialized reproductive structures, which are sometimes called vegetative propagules.
Many plants naturally reproduce this way, but it can also be induced
artificially.
Horticulturists have developed asexual propagation techniques that use vegetative propagules to replicate plants. Success rates and difficulty of propagation vary greatly.
Monocotyledons typically lack a
vascular cambium, making them more challenging to propagate. (Full article...)
True carnivory is believed to have
evolved independently at least 12 times in five different
orders of flowering plants, and is represented by more than a dozen
genera. This classification includes at least 583 species that attract, trap, and kill
prey, absorbing the resulting available nutrients.
Venus flytrap (Dionaea muscipula),
pitcher plant (Cephalotus follicularis), and
bladderwort (Utricularia gibba) can be seen as exemplars of key traits genetically associated with carnivory: trap leaf development, prey digestion, and nutrient absorption. (Full article...)
Agroforestry can be practiced for economic, environmental, and social benefits, and can be part of
sustainable agriculture. Apart from production, benefits from agroforestry include improved farm productivity, healthier environments, reduction of risk for farmers, beauty and aesthetics, increased farm profits, reduced soil erosion, creating wildlife habitat, less pollution, managing animal waste, increased biodiversity, improved soil structure, and
carbon sequestration. (Full article...)
Nectar is an economically important substance as it is the sugar source for
honey. It is also useful in
agriculture and
horticulture because the adult stages of some predatory insects feed on nectar. For example, a number of predacious or
parasitoid wasps (e.g., the social wasp species Apoica flavissima) rely on nectar as a primary food source. In turn, these wasps then hunt agricultural pest insects as food for their young. (Full article...)
Opuntia, commonly called the prickly pear cactus, is a
genus of
flowering plants in the
cactusfamily Cactaceae, many known for their flavorful fruit and showy flowers. Cacti are well-adapted to aridity, however, they are still vulnerable to alterations in precipitation and temperature driven by climate change. Prickly pear alone is more commonly used to refer exclusively to the fruit, but may also be used for the plant itself; in addition, other names given to the plant and its specific parts include tuna (fruit), sabra, sabbar, nopal (pads, plural nopales) from the
Nahuatl word nōpalli, nostle (fruit) from the Nahuatl word nōchtli, and paddle cactus. The genus is named for the
Ancient Greek city of
Opus, where, according to
Theophrastus, an edible plant grew and could be propagated by rooting its leaves. The most common
culinary species is the "Barbary fig" (Opuntia ficus-indica). (Full article...)
Prunus is a genus of
trees and
shrubs in the
flowering plant family
Rosaceae that includes
plums,
cherries,
peaches,
nectarines,
apricots, and
almonds. The genus has a cosmopolitan distribution, being native to the North American temperate regions, the
neotropics of South America, and temperate and tropical regions of Asia and Africa, There are 340 accepted species. Many members of the genus are widely cultivated for their fruit and for decorative purposes. Prunus fruit are
drupes, or stone fruits. The fleshy
mesocarp surrounding the
endocarp is edible while the endocarp itself forms a hard, inedible shell called the
pyrena ("stone" or "pit"). This shell encloses the seed (or "kernel"), which is edible in some species (such as sweet almonds), but poisonous in many others (such as
apricots). Besides being eaten off the hand, most Prunus fruit are also commonly used in processing, such as jam production, canning, drying, and the seeds for roasting. (Full article...)
Most commonly purple, the spongy, absorbent fruit is used in
several cuisines. Typically used as a
vegetable in cooking, it is a
berry by
botanical definition. As a member of the genus Solanum, it is related to the
tomato,
chili pepper, and
potato, although those are of the
New World while the eggplant is of the
Old World. Like the tomato, its skin and seeds can be eaten, but, like the potato, it is usually eaten cooked. Eggplant is nutritionally low in
macronutrient and
micronutrient content, but the capability of the fruit to absorb oils and flavors into its flesh through cooking expands its use in the
culinary arts. (Full article...)
Image 9
A parasitic plant is a
plant that derives some or all of its nutritional requirements from another living plant. They make up about 1% of
angiosperms and are found in almost every
biome. All
parasitic plants develop a specialized organ called the
haustorium, which penetrates the host plant, connecting them to the host vasculature – either the
xylem,
phloem, or both. For example, plants like Striga or Rhinanthus connect only to the xylem, via xylem bridges (xylem-feeding). Alternately,
plants like Cuscuta and some members of Orobanche connect to both the xylem and phloem of the host. This provides them with the ability to extract resources from the host. These resources can include water, nitrogen, carbon and/or sugars. Parasitic plants are classified depending on the location where the parasitic plant latches onto the host (root or stem), the amount of nutrients it requires, and their photosynthetic capability. Some parasitic plants can locate their
host plants by detecting volatile
chemicals in the air or soil given off by host
shoots or
roots, respectively. About 4,500
species of parasitic plants in approximately 20 families of
flowering plants are known.
There is a wide range of effects that may occur to a host plant due to the presence of a parasitic plant. Often there is a pattern of stunted growth in hosts especially in hemi-parasitic cases, but may also result in higher mortality rates in host plant species following introduction of larger parasitic plant populations. (Full article...)
Image 10
Legumes (/ˈlɛɡjuːm,ləˈɡjuːm/) are plants in the family
Fabaceae (or Leguminosae), or the fruit or seeds of such plants. When used as a dry grain for human consumption, the seeds are also called pulses. Legumes are grown agriculturally, primarily for human consumption; for livestock forage and
silage; and as soil-enhancing
green manure. Well-known legumes include beans, chickpeas, peanuts, lentils, lupins,
mesquite, carob, tamarind, alfalfa, and clover. Legumes produce a botanically unique type of fruit – a
simple dry fruit that develops from a simple
carpel and usually
dehisces (opens along a seam) on two sides.
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...)
NYBG is also a major educational institution, teaching visitors about plant science, ecology, and healthful eating through NYBG's interactive programming. Nearly 90,000 of the annual visitors are children from underserved neighboring communities. An additional 3,000 are teachers from New York City's public school system participating in professional development programs that train them to teach science courses at all grade levels. NYBG operates one of the world's largest plant research and conservation programs. (Full article...)
Cornus is a
genus of about 30–60
species of
woody plants in the
familyCornaceae, commonly known as dogwoods or cornels, which can generally be distinguished by their blossoms, berries, and distinctive bark. Most are
deciduoustrees or
shrubs, but a few species are nearly herbaceous
perennial subshrubs, and some species are
evergreen. Several species have small heads of inconspicuous flowers surrounded by an
involucre of large, typically white petal-like
bracts, while others have more open clusters of
petal-bearing flowers. The various species of dogwood are
native throughout much of
temperate and
boreal Eurasia and North America, with China, Japan, and the southeastern United States being particularly rich in native species.
Species include the common dogwood Cornus sanguinea of Eurasia, the widely cultivated flowering dogwood (
Cornus florida) of eastern North America, the Pacific dogwood Cornus nuttallii of western North America, the Kousa dogwood Cornus kousa of eastern Asia, and two low-growing boreal species, the Canadian and Eurasian dwarf cornels (or bunchberries), Cornus canadensis and Cornus suecica respectively. (Full article...)
The dicotyledons, also known as dicots (or, more rarely, dicotyls), are one of the two groups into which all the
flowering plants (angiosperms) were formerly divided. The name refers to one of the typical characteristics of the group: namely, that the
seed has two embryonic leaves or
cotyledons. There are around 200,000
species within this group. The other group of flowering plants were called
monocotyledons (or monocots), typically each having one cotyledon. Historically, these two groups formed the two divisions of the flowering plants.
Largely from the 1990s onwards,
molecular phylogenetic research confirmed what had already been suspected: that dicotyledons are not a group made up of all the descendants of a common ancestor (i.e., they are not a
monophyletic group). Rather, a number of lineages, such as the
magnoliids and groups now collectively known as the
basal angiosperms, diverged earlier than the monocots did; in other words, monocots evolved from within the dicots, as traditionally defined. The traditional dicots are thus a
paraphyletic group. (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.
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Image 1
The lily
family, Liliaceae, consists of about 15
genera and 610
species of
flowering plants within the
orderLiliales. They are
monocotyledonous,
perennial,
herbaceous, often
bulbousgeophytes. Plants in this family have evolved with a fair amount of morphological diversity despite genetic similarity. Common characteristics include large flowers with parts arranged in threes: with six colored or patterned
petaloidtepals (undifferentiated petals and sepals) arranged in two
whorls, six
stamens and a superior
ovary. The leaves are linear in shape, with their veins usually arranged parallel to the edges, single and arranged alternating on the stem, or in a rosette at the base. Most species are grown from bulbs, although some have
rhizomes. First described in 1789, the lily family became a
paraphyletic "catch-all" (
wastebasket) group of
lilioid monocots that did not fit into other families and included a great number of genera now included in other families and in some cases in other orders. Consequently, many sources and descriptions labelled "Liliaceae" deal with the broader sense of the family.
The family evolved approximately 68
million years ago during the
Late Cretaceous to
Early Paleogene epochs. Liliaceae are widely distributed, mainly in temperate regions of the Northern Hemisphere and the flowers are insect pollinated. Many Liliaceae are important
ornamental plants, widely grown for their attractive flowers and involved in a major
floriculture of
cut flowers and dry bulbs. Some species are
poisonous if eaten and can have adverse health effects in humans and household pets. (Full article...)
Wheat is grown on more land area than any other food crop (220.7 million hectares or 545 million acres in 2021). World trade in wheat is greater than for all other crops combined. In 2021, world wheat production was 771 million
tonnes (850 million short tons), making it the second most-produced cereal after
maize (known as corn in North America and Australia; wheat is often called corn in countries including Britain). Since 1960, world production of wheat and other grain crops has tripled and is expected to grow further through the middle of the 21st century. Global demand for wheat is increasing because of the usefulness of
gluten to the food industry. (Full article...)
Image 3
Betula pubescens (syn. Betula alba), commonly known as downy birch and also as moor birch, white birch, European white birch or hairy birch, is a species of
deciduous tree, native and abundant throughout northern
Europe and northern
Asia, growing farther north than any other
broadleaf tree. It is closely related to, and often confused with, the
silver birch (B. pendula), but grows in wetter places with heavier soils and poorer drainage; smaller trees can also be confused with the
dwarf birch (B. nana).
Six varieties are recognised and it hybridises with the silver and dwarf birches. A number of cultivars have been developed but many are no longer in cultivation. The larva of the
autumnal moth (Epirrita autumnata) feeds on the foliage and in some years, large areas of birch forest can be defoliated by this insect. Many fungi are associated with the tree and certain pathogenic fungi are the causal agents of
birch dieback disease. (Full article...)
Image 4
Dracophyllum arboreum, commonly known as Chatham Island grass tree and tarahinau (
Moriori), is a species of tree in the heath family
Ericaceae. Endemic to the
Chatham Islands of New Zealand, it reaches a height of 18 m (60 ft) and has leaves that differ between the juvenile and adult forms.
D. arboreum has wide light green leaves in its juvenile form, which become thin needles as it gains maturity. Flowering occurs from November through to February, yielding small white flowers which later become tiny brown fruit. It inhabits many different types of
vegetation communities from near sea level to 270 m (886 ft), including swamps, cliffs, bogs, and shrublands. It has a range restricted to three Islands some 800 km (497 mi) east of New Zealand: the
Chatham,
Pitt, and
Rangatira Islands. (Full article...)
Image 5
Ornithogalum umbellatum, the garden star-of-Bethlehem, grass lily, nap-at-noon, or eleven-o'clock lady, a species of the genus Ornithogalum, 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 most of 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...)
First collected in 1984 near the
wheatbelt town of
Wagin, Banksia oligantha was officially described in 1987 by Australian botanist
Alex George. Several scattered populations survive in fragments of remnant bushland in a region which has been mostly cleared for agriculture. It has been listed as Declared Rare Flora by the Western Australian Government. (Full article...)
Image 7
A juniper berry is the female
seed cone produced by the various species of
junipers. It is not a true
berry but a cone with unusually fleshy and merged scales called a
galbulus, which gives it a berry-like appearance. The cones from a handful of species, especially Juniperus communis, are used as a
spice, particularly in
European cuisine, and also give
gin its distinctive flavour. Juniper berries are among the only spices derived from
conifers, along with
spruce buds. (Full article...)
Eucalyptus gomphocephala, known as tuart, is a species of tree and is one of the six forest giants of
Southwest Australia.The trees usually grow to a height of 10 to 40 m (33 to 131 ft) and mostly have a single stem, but can have multiple stems under some conditions. The
crown can be as wide as 25 metres (82 ft). It has rough
box-like bark over the length of the trunk and larger branches. The glossy light-green to green adult leaves are arranged alternately and have an
oval to
lanceolate or
falcate shape, and have a leaf blade that is 90 to 180 millimetres (3.5 to 7.1 in) long and 1.5 to 3 cm (0.59 to 1.18 in) wide. The tree flowers between January and April with white to cream
inflorescences that form in the leaf
axils and are not branched. The fruits that follow have an
obconic to upside-down bell shape. (Full article...)
The orange originated in a region encompassing
Southern China,
Northeast India, and
Myanmar; the earliest mention of the sweet orange was in
Chinese literature in 314 BC. Orange trees are widely grown for their sweet fruit. The fruit of the
orange tree can be eaten fresh, or processed for its juice or fragrant
peel. In 2022, 76 million
tonnes of oranges were grown worldwide, with
Brazil producing 22% of the total, followed by
India and
China. (Full article...)
Roystonea regia, commonly known as the royal palm, Cuban royal palm, or Florida royal palm, is a species of
palm native to
Mexico, the
Caribbean,
Florida, and parts of
Central America. 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 15–24 m (50–80 ft) 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
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...)
Image 11
Acer rubrum, the red maple, also known as swamp maple, water maple, or soft maple, is one of the most common and widespread deciduous
trees of eastern and central North America. The
U.S. Forest Service recognizes it as the most abundant native tree in eastern North America. The red maple ranges from southeastern
Manitoba around the
Lake of the Woods on the border with
Ontario and
Minnesota, east to
Newfoundland, south to
Florida, and southwest to
East Texas. Many of its features, especially its leaves, are quite variable in form. At maturity, it often attains a height around 30 m (100 ft). Its flowers, petioles, twigs, and seeds are all red to varying degrees. Among these features, however, it is best known for its brilliant deep scarlet foliage in autumn.
Over most of its range, red maple is adaptable to a very wide range of site conditions, perhaps more so than any other tree in eastern North America. It can be found growing in
swamps, on poor, dry
soils, and almost anywhere in between. It grows well from
sea level to about 900 m (3,000 ft). Due to its attractive fall foliage and pleasing form, it is often used as a shade tree for landscapes. It is used commercially on a small scale for
maple syrup production and for its medium to high quality lumber. It is also the
state tree of Rhode Island. The red maple can be considered weedy or even invasive in young, highly disturbed forests, especially frequently logged forests. In a mature or old-growth northern hardwood forest, red maple only has a sparse presence, while shade-tolerant trees such as sugar maples,
beeches, and
hemlocks thrive. By removing red maple from a young forest recovering from disturbance, the natural cycle of forest regeneration is altered, changing the diversity of the forest for centuries to come. (Full article...)
Marsileaceae (/mɑːrˌsɪliˈeɪsi.iː/) is a small
family of
heterosporousaquatic and semi-aquatic
ferns, though at first sight they do not physically resemble other ferns. The group is commonly known as the "pepperwort family" or as the "water-clover family" because the leaves of the genus Marsilea superficially resemble the leaves of a
four-leaf clover. In all, the family contains 3
genera and 50 to 80 species with most of those belonging to Marsilea. (Full article...)
The
taxonomy of the plant family
Liliaceae has had a complex history since its first description in the mid-eighteenth century. Originally, the Liliaceae were defined as having a "
calix" (perianth) of six equal-coloured parts, six
stamens, a single
style, and a superior, three-chambered (trilocular)
ovary turning into a
capsule fruit at maturity. The taxonomic
circumscription of the family Liliaceae progressively expanded until it became the largest plant family and also extremely diverse, being somewhat arbitrarily defined as all species of plants with six
tepals and a superior ovary. It eventually came to encompass about 300
genera and 4,500
species, and was thus a "
catch-all" and hence
paraphyletic. Only since the more modern taxonomic systems developed by the
Angiosperm Phylogeny Group (APG) and based on
phylogenetic principles, has it been possible to identify the many separate taxonomic groupings within the original family and redistribute them, leaving a relatively small core as the modern family Liliaceae, with fifteen genera and 600 species.
Wild
species of cherry tree are widely distributed, mainly in the Northern Hemisphere. They are common in East Asia, especially in
Japan, where they have been cultivated, producing many varieties. (Full article...)
Image 15
Cultivar belonging to the Schlumbergera Truncata Group
Schlumbergera is a small
genus of
cacti with six to nine species found in the coastal mountains of south-eastern
Brazil. These plants grow on trees or rocks in habitats that are generally shady with high humidity, and can be quite different in appearance from their
desert-dwelling cousins. Most species of Schlumbergera have stems which resemble leaf-like pads joined one to the other and flowers which appear from
areoles at the joints and tips of the stems. Two species have cylindrical stems more similar to other cacti.
Common names for these cacti generally refer to their flowering season. In the Northern Hemisphere, they are called Christmas cactus, Thanksgiving cactus, crab cactus and holiday cactus. In Brazil, the genus is referred to as Flor de Maio (May flower), reflecting the period in which they flower in the Southern Hemisphere. Most of the popular houseplants are
cultivars of Schlumbergera, rather than species, with flowers in white, pink, yellow, orange, red or purple. The Easter cactus or Whitsun cactus, placed in the genus Rhipsalidopsis, is also called a holiday cactus and has flowers in red, orange, pink and white. (Full article...)
... that according to Lois N. Magner,
Hildegard of Bingen's Physica is "probably the first book by a female author to discuss the elements and the therapeutic virtues of plants, animals, and metals"?
Image 6Leaf lamina. The megaphyllous
leaf architecture arose multiple times in different plant lineages (from Evolutionary history of plants)
Image 7A botanist preparing a plant specimen for mounting in the
herbarium (from Botany)
Image 81 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 13The 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 14A
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 15Transverse section of a fossil stem of the Devonian vascular plant Rhynia gwynne-vaughani (from Botany)
Image 16A nineteenth-century illustration showing the morphology of the roots, stems, leaves and flowers of the rice plant Oryza sativa (from Botany)
Image 17The branching pattern of megaphyll veins may indicate their origin as webbed, dichotomising branches. (from Evolutionary history of plants)
Image 18The 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 19The
Linnaean Garden of Linnaeus' residence in Uppsala, Sweden, was planted according to his Systema sexuale. (from Botany)
Image 20Structure of a plant cell (from Plant cell)
Image 25Micropropagation of transgenic plants (from Botany)
Image 26The trunk of early tree fern Psaronius, showing internal structure. The top of the plant would have been to the left of the image (from Evolutionary history of plants)
Image 29This is an electron micrograph of the epidermal cells of a Brassica chinensis leaf. The stomates are also visible. (from Plant cell)
Image 30Structure 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 31Echeveria glauca in a Connecticut greenhouse. Botany uses Latin names for identification; here, the specific name glauca means blue. (from Botany)
Image 32The 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 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)