Oenanthe sarmentosa is a species of flowering plant in the family Apiaceae known by the common name water parsley. It is native to western North America from Alaska to California, where it grows in wet areas, such as streambanks. It is sometimes aquatic, growing in the water. The plant has been used in cultivation in wetlands, and the recent discovery of several colonies growing by a stream in Illinois demonstrates its capacity to become a noxious weed if it is introduced elsewhere. This is a perennial herb growing to a maximum height near 1.5 meters. The leaves have blades up to 30 centimeters long borne on petioles up to 35 centimeters in length. The parsley-like leaf blade is divided into serrated, lobed leaflets. The inflorescence is a compound umbel of many flowers with bright white to red-tinged petals.


Oenothera caespitosa, known commonly as tufted evening primrose, desert evening primrose, rock-rose evening primrose, or fragrant evening primrose, is a perennial plant of the genus Oenothera native to much of western and central North America, in habitats such as talus slopes and sandy plains. It is normally night-blooming.
The plant is considered good for rock gardens. There are many subtaxa, referred to as subspecies or varieties.


Oenothera caespitosa grows to 10 centimeters (4 inches) tall. It produces a rosette of lobed or toothed leaves each up to 36 centimetres (14 in) long around a woody caudex. It has no stems, with flowers and leaves growing directly from the root crown. The four-petaled white flowers open at dusk and wilt the next morning, turning pink. The petals measure up to 5 cm (2 in) in width and length. A notch gives them a heart shape.


Oenothera deltoides is very similar, with short stems and slightly smaller flowers.


It is an annual plant growing to 0.2–2 m (rarely 3 m) tall, unbranched, or if branched, only below the flower spikes. The leaves are 2–20 cm (0.79–7.87 in) long, lance-shaped, and are covered with soft hair. The flower spikes are 20–30 cm (7.9–11.8 in) long, covered with green flower buds, which open at night or before dawn with small flowers 5 mm (0.20 in) diameter with four pink petals.


It is naturalized and often invasive in other parts of the United States, and in Australia, China, Japan, and South America.


Oenothera elata is a species of Oenothera known by the common name Hooker's evening primrose or tall evening primrose. Subspecies include hookeri, hirsutissima, longisima, jamesii, villosa and elata. It is native to much of western and central North America. The plants are quite tall, especially the hookeri subspecies, native to California, which can reach about 1.8 meters (6 feet) height.  The plants are found along roadsides, in moist meadows, or woodland, from sea level up to 9,000 ft (2,700 m) in elevation.


The stout, usually reddish stem has many long, narrow leaves, above a basal rosette. At its top is a large, open cluster of 2- to 4-inch wide yellow flowers with 4 large petals and protruding yellow stamens and 4-branched pistil, often covered in sticky pollen. The fragrant flowers open at dusk and wilt the next morning, turning orange or red.


Oenothera macrocarpa (syn. Oenothera missouriensis), the bigfruit evening primrose, Ozark sundrop or Missouri evening primrose, is a species of flowering plant in the evening primrose family Onagraceae, native to Mexico and the south-central United States, where it is found in calcareous prairies and limestone outcrops.


This herbaceous perennial produces a red stem 6–12 in. (15–30 cm) in height. The large (3 inch) wide flowers are cup shaped, canary yellow and have a mild fragrance. They are produced in great numbers from early to mid summer. Leaves are dark green and lanceolate, and bunched along the trailing stem. The seed pods are 4-winged and 2 to 3 inch long.


The seed pods are often used in flower arrangements. This plant is also grown in gardens for its flowers. It is suitable as a groundcover in poor, stony soil which does not become waterlogged in winter, in full sun. It has gained the Royal Horticultural Society’s Award of Garden Merit.


There are five commonly accepted varieties. These are:
O. macrocarpa var. fremontii - restricted to Kansas and southern Nebraska
O. macrocarpa var. incana - southern Kansas, western Oklahoma and northern Texas
O. macrocarpa var. macrocarpa - the most widespread; Texas to the Ozark Mountains, with disjunct populations in Tennessee's Nashville Basin
O. macrocarpa var. mexicana - known only from Coahuila, Mexico
O. macrocarpa var. oklahomensis - southern Kansas, Oklahoma and northern Texas


Oenothera rosea, also known as rosy evening-primrose, rose evening primrose, pink evening primrose, or Rose of Mexico, is a plant belonging to the genus Oenothera and native to northern Mexico and Texas.
Oenothera rosea has flowers with less than 2.5 cm (0.98 in) diameter. The shade varies from pink to red.


Over centuries, Indigenous people in North America were using the plant as food and traditional medicine.
The evening primrose was introduced to Europe in the early 17th century as an ornamental plant in botanical gardens where its flowers are favored for nectar by hummingbirds and its seeds supply food for other birds.


Most of the plant parts are edible, having a taste that is mild. The roots can be eaten raw or cooked like potatoes. The leaves can be eaten raw in salads or cooked like spinach or in soups. Native American tribes made tea from the evening primrose leaves and used it as a dietary aid.
The flowering stems are preferably used when they are still young in June. They have to be peeled and can then be eaten raw or fried. The flower buds are denoted as a delicacy and can be harvested from June to October.
The seeds have a protein content of about 15%, an oil content of 24%, and contain about 43% cellulose. The proteins are especially rich in the sulphur-containing amino acids, methionine and cysteine, and tryptophan. Gamma-linolenic acid (GLA), and linoleic acid are present. Mainly for these polyunsaturated fatty acids, evening primrose oil is sold as a dietary supplement.


The knowledge of agricultural practices in the cultivation of evening primrose is relatively new and only pertain to the commercialized production of evening primrose seed oil. Information of agricultural practices for the production of root vegetable or other plant parts is not known yet.
The evening primrose prefers sunny, and arid places with loamy soil and occurs below 700 metres (2,300 ft) above sea level. One important prerequisite is to meet adequate nitrogen requirements. While too high nitrogen levels could lead to a quality and quantity decline of the oil content in the seeds, moderate nitrogen levels lead to increased seed quality and quantity. Because the evening primrose is a light-dependent germinator, it is important that the seeds are not planted too deep into the soil, about 0.5–1.0 centimetre (0.2–0.4 in) deep. The cultivation of evening primrose is thus suitable for no-till farming, but the plants require an intense mechanical weed control. The seeds are tiny, about 0.3–0.7 grams (0.011–0.025 oz). They need approximately two to three weeks to germinate and are therefore very susceptible to the outgrowth of weeds.
Evening primrose seeds can be sown in the first half of April (spring seeds) or from mid-July to mid-August (autumn seeds). The time of harvest is approximately 75 to 80 days (spring seeds) or 100 days (autumn seeds) after flowering, and clearly influenced by the plant variety, climate conditions, soil fertility and sowing time. The population development and thus seed maturation of the evening primrose is very heterogeneous which is a rather difficult production factor.
There is not much water needed during the vegetation period. A study has shown, that the irrigation with salt water could increase the oil yield and quality in evening primrose seeds. This might be a great opportunity especially in regions with limited water resources. Thus, the evening primrose could be a valuable alternative oil crop in arid regions.
Finally, the cultivation of evening primrose requires a proper field management otherwise the plant can become invasive. If the seeds are used for pharmaceutical purposes it is also  important to grow the evening primrose without any pesticides to avoid any chemical residues.


Oenothera speciosa is a herbaceous perennial wildflower. It has glabrous (smooth) to pubescent stems that grow to 50 centimetres (20 inches) in height. The pubescent leaves are alternate with very short or no petiole (sessile), reaching 10 cm (4 in) long to 4 cm (1+1⁄2 in) broad. They are variable in shape, from linear to obovate, and are toothed or wavy-edged. It produces single, four-petaled, cup-shaped flowers on the upper leaf axils. These fragrant shell-pink flowers bloom throughout the summer into early autumn. The 4–5 cm (1+1⁄2–2 in) flowers start out white and turn pink as they age.
The flower throats, as well as the stigmas and stamens, have a soft yellow color. It blooms both day and night, but typically in the pre-dawn hours, closing when the full sun hits them. They bloom from March to July, and occasionally in the fall. The flowers are frequented by several insect species, but moths are the most common as the flowers are mostly open at night.


The specific name, speciosa, means "showy".
This plant is frequently referred to as a buttercup, though it is not a true buttercup (genus Ranunculus), or even in the buttercup family, Ranunculaceae.


The species has the following varieties:
Oenothera speciosa var. berlandieri (Spach) Munz
Oenothera speciosa var. childsii (L.H. Bailey) Munz
Oenothera speciosa var. speciosa


Originally native to the grasslands of Kansas, Missouri, Nebraska, northeastern New Mexico, Oklahoma, and Texas, it has been naturalized in 28 of the lower 48 U.S. states as well as Chihuahua and Coahuila in Mexico. It frequently escapes from gardens.
The plant's wild habitat includes rocky prairies, open woodlands, slopes, roadsides, meadows and disturbed areas. While it makes an attractive garden plant, care should be taken with it as it can become invasive, spreading by runners and seeds. This drought-resistant plant prefers loose, fast-draining soil and full sun. It is a groundcover.
The pink evening primrose is used in the temperate latitudes as an ornamental plant, but does not survive severe winters. Within the United States Department of Agriculture's hardiness zone climates 4 to 9, and in most areas of Central Europe, the species should be sufficiently hardy. In Europe plant has been reported to cause deaths of eurasian hummingbird hawk-moth as they get stuck into the flower while foraging.


The green plant parts can be cooked or eaten as a salad; the taste is pleasant when harvested before flowers develop.


Oenothera suffulta, known as roadside gaura, honeysuckle gaura, or kisses, is a flowering plant in the primrose family, Onagraceae. It is endemic to the United States, in Texas (excluding the Trans-Pecos) and southern Oklahoma.


Roadside gaura was first formally named in 1850 as Gaura suffulta. It was transferred to the genus Oenothera in 2007.
It is most closely related to Oenothera patriciae and Oenothera triangulata.


Oenothera suffulta is an annual herb, of open, sandy places. It grows up to 120 cm (3.9 ft) tall. The basal leaves form a rosette; each leaf is up to 11 cm (4.3 in) long and 2.3 cm (0.91 in) across. The stem leaves (cauline leaves) are alternate, simple, and range from 1–9 cm (0.4–3.5 in) long, with smooth, wavy, or toothed edges. The lower leaf surface is softly, velvety hairy.
Roadside gaura flowers from April to June. Each plant produces a spike of closely packed flowers; several flowers open each day, around sunset. The flowers are relatively scentless. The flower has four long, white petals, each petal 10–15 mm (0.4–0.6 in) long and narrowed at the base. The fruit is a woody, indehiscent capsule with broad wings on the angles.


Oenothera triloba, with common names stemless evening primrose and sessile evening primrose is a flowering plant in the primrose family. It is native to North America, where it is primarily found in northern Mexico and in the south-central United States. It is found in dry, open areas such as glades, prairies, and sometimes even lawns. It appears to respond positively to soil disturbance.
It is a winter annual that produces large yellow flowers in the spring. The flowers open near sunset.


Among the Zuni people, the plant is used as an ingredient of "schumaakwe cakes" and used externally for rheumatism and swelling. They also grind the roots and use them as food.


The olive, botanical name Olea europaea, meaning 'European olive' in Latin, is a species of small tree or shrub in the family Oleaceae, found traditionally in the Mediterranean Basin. When in shrub form, it is known as Olea europaea 'Montra', dwarf olive, or little olive. The species is cultivated in all the countries of the Mediterranean, as well as in Australia, New Zealand, North and South America and South Africa. Olea europaea is the type species for the genus Olea.
The olive's fruit, also called an "olive", is of major agricultural importance in the Mediterranean region as the source of olive oil; it is one of the core ingredients in Mediterranean cuisine. The tree and its fruit give their name to the plant family, which also includes species such as lilac, jasmine, forsythia, and the true ash tree.
Hundreds of cultivars of the olive tree are known. Olive cultivars may be used primarily for oil, eating, or both. Olives cultivated for consumption are generally referred to as "table olives". About 90% of all harvested olives are turned into oil, while about 10% are used as table olives.


The word olive derives from Latin ŏlīva ("olive fruit", "olive tree"), possibly through Etruscan 𐌀𐌅𐌉𐌄𐌋𐌄 (eleiva) from the archaic Proto-Greek form *ἐλαίϝα (*elaíwa) (Classic Greek ἐλαία elaía, "olive fruit", "olive tree"). The word oil originally meant "olive oil", from ŏlĕum, ἔλαιον (élaion, "olive oil"). Also in multiple other languages the word for "oil" ultimately derives from the name of this tree and its fruit. The oldest attested forms of the Greek words are the Mycenaean 𐀁𐀨𐀷, e-ra-wa, and 𐀁𐀨𐀺, e-ra-wo or 𐀁𐁉𐀺, e-rai-wo, written in the Linear B syllabic script.


The olive tree, Olea europaea, is an evergreen tree or shrub native to Mediterranean Europe, Asia, and Africa. It is short and squat and rarely exceeds 8–15 m (25–50 ft) in height. 'Pisciottana', a unique variety comprising 40,000 trees found only in the area around Pisciotta in the Campania region of southern Italy, often exceeds this, with correspondingly large trunk diameters. The silvery green leaves are oblong, measuring 4–10 cm (1+1⁄2–4 in) long and 1–3 cm (3⁄8–1+3⁄16 in) wide. The trunk is typically gnarled and twisted.
The small, white, feathery flowers, with ten-cleft calyx and corolla, two stamens, and bifid stigma, are borne generally on the previous year's wood, in racemes springing from the axils of the leaves.
The fruit is a small drupe 1–2.5 cm (3⁄8–1 in) long when ripe, thinner-fleshed and smaller in wild plants than in orchard cultivars. Olives are harvested in the green to purple stage. Canned black olives have often been artificially blackened (see below on processing) and may contain the chemical ferrous gluconate to improve the appearance. Olea europaea contains a pyrena commonly referred to in American English as a "pit", and in British English as a "stone".


The six natural subspecies of Olea europaea are distributed over a wide range:
Olea europaea subsp. europaea (Mediterranean Basin)
Olea europaea var. sylvestris, considered the "wild" olive of the Mediterranean, is a variety characterized by a smaller tree bearing noticeably smaller fruit.
O. e. subsp. cuspidata (from South Africa throughout East Africa, Arabia to Southwest China)
O. e. subsp. cerasiformis (Madeira); also known as Olea maderensis
O. e. subsp. guanchica (Canary Islands)
O. e. subsp. laperrinei (Algeria, Sudan, Niger)
O. e. subsp. maroccana (Morocco)
The subspecies O. e. cerasiformis is tetraploid, and O. e. maroccana is hexaploid. Wild-growing forms of the olive are sometimes treated as the species Olea oleaster. The trees referred to as "white" and "black" olives in Southeast Asia are not actually olives but species of Canarium.


Hundreds of cultivars of the olive tree are known. An olive's cultivar has a significant impact on its color, size, shape, and growth characteristics, as well as the qualities of olive oil. Olive cultivars may be used primarily for oil, eating, or both. Olives cultivated for consumption are generally referred to as "table olives".
Since many olive cultivars are self-sterile or nearly so, they are generally planted in pairs with a single primary cultivar and a secondary cultivar selected for its ability to fertilize the primary one. In recent times, efforts have been directed at producing hybrid cultivars with qualities useful to farmers, such as resistance to disease, quick growth, and larger or more consistent crops.


Fossil evidence indicates the olive tree had its origins 20–40 million years ago in the Oligocene, in what is now corresponding to Italy and the eastern Mediterranean Basin. Around 100, 000 years ago, olives were used by humans in Africa, on the Atlantic coast of Morocco, for fuel management and most probably for consumption. Wild oleasters were present and collected in the Eastern Mediterranean since ~19,000 BP. The genome of cultivated olives reflects their origin from oleaster populations in the Eastern Mediterranean. The olive plant was first cultivated some 7,000 years ago in Mediterranean regions.
The edible olive seems to have coexisted with humans for about 5,000 to 6,000 years, going back to the early Bronze Age (3150 to 1200 BC). Its origin can be traced to the Levant based on written tablets, olive pits, and wood fragments found in ancient tombs. As far back as 3000 BC, olives were grown commercially in Crete; they may have been the source of the wealth of the Minoan civilization.
The ancestry of the cultivated olive is unknown. Fossil olea pollen has been found in Macedonia and other places around the Mediterranean, indicating that this genus is an original element of the Mediterranean flora. Fossilized leaves of olea were found in the palaeosols of the volcanic Greek island of Santorini and dated to about 37,000 BP. Imprints of larvae of olive whitefly Aleurobus olivinus were found on the leaves. The same insect is commonly found today on olive leaves, showing that the plant-animal co-evolutionary relations have not changed since that time. Other leaves found on the same island are dated back to 60,000 BP, making them the oldest known olives from the Mediterranean.


Olives are not native to the Americas. Spanish colonists brought the olive to the New World, where its cultivation prospered in present-day Peru, Chile, and Argentina. The first seedlings from Spain were planted in Lima by Antonio de Rivera in 1560. Olive tree cultivation quickly spread along the valleys of South America's dry Pacific coast where the climate was similar to the Mediterranean. Spanish missionaries established the tree in the 18th century in California. It was first cultivated at Mission San Diego de Alcalá in 1769 or later around 1795. Orchards were started at other missions, but in 1838, an inspection found only two olive orchards in California. Cultivation for oil gradually became a highly successful commercial venture from the 1860s onward.
In Japan, the first successful planting of olive trees happened in 1908 on Shodo Island, which became the cradle of olive cultivation in Japan.
An estimated 865 million olive trees were in the world as of 2005, and the vast majority of these were found in Mediterranean countries, with traditionally marginal areas accounting for no more than 25% of olive-planted area and 10% of oil production.


Olive oil has long been considered sacred and holy. The olive branch has often been a symbol of abundance, glory, and peace. The leafy branches of the olive tree were ritually offered to deities and powerful figures as emblems of benediction and purification, and they were used to crown the victors of friendly games and bloody wars. Today, olive oil is still used in many religious ceremonies. Over the years, the olive has also been used to symbolize wisdom,  fertility, power, and purity.


Olives are thought to have been domesticated in the third millennium BC at the latest, at which point they, along with grain and grapes, became part of Colin Renfrew's triad of Greek staple crops that fueled the emergence of more complex societies. Olives, and especially (perfumed) olive oil, became a major export product during the Minoan and Mycenaean periods. Dutch archaeologist Jorrit Kelder proposed that the Mycenaeans sent shipments of olive oil, probably alongside live olive branches, to the court of the Egyptian pharaoh Akhenaten as a diplomatic gift. In Egypt, these imported olive branches may have acquired ritual meanings, as they are depicted as offerings on the wall of the Aten temple and were used in wreaths for the burial of Tutankhamun. It is likely that, as well as being used for culinary purposes, olive oil was also used to various other ends, including as a perfume.
The ancient Greeks smeared olive oil on their bodies and hair as a matter of grooming and good health. Olive oil was used to anoint kings and athletes in ancient Greece. It was burnt in the sacred lamps of temples and was the "eternal flame" of the original Olympic games. Victors in these games were crowned with its leaves. In Homer's Odyssey, Odysseus crawls beneath two shoots of olive that grow from a single stock, and in the Iliad, (XVII.53ff) there is a metaphoric description of a lone olive tree in the mountains, by a spring; the Greeks observed that the olive rarely thrives at a distance from the sea, which in Greece invariably means up mountain slopes. Greek myth attributed to the primordial culture-hero Aristaeus the understanding of olive husbandry, along with cheese-making and bee-keeping. Olive was one of the woods used to fashion the most primitive Greek cult figures, called xoana, referring to their wooden material; they were reverently preserved for centuries.
It was purely a matter of local pride that the Athenians claimed that the olive grew first in Athens. In an archaic Athenian foundation myth, Athena won the patronage of Attica from Poseidon with the gift of the olive. According to the fourth-century BC father of botany, Theophrastus, olive trees ordinarily attained an age around 200 years, he mentions that the very olive tree of Athena still grew on the Acropolis; it was still to be seen there in the second century AD; and when Pausanias was shown it  c. 170 AD, he reported "Legend also says that when the Persians fired Athens the olive was burnt down, but on the very day it was burnt it grew again to the height of two cubits." Indeed, olive suckers sprout readily from the stump, and the great age of some existing olive trees shows that it was possible that the olive tree of the Acropolis dated to the Bronze Age. The olive was sacred to Athena and appeared on the Athenian coinage.
Theophrastus, in On the Causes of Plants, does not give as systematic and detailed an account of olive husbandry as he does of the vine, but he makes clear (in 1.16.10) that the cultivated olive must be vegetatively propagated; indeed, the pits give rise to thorny, wild-type olives, spread far and wide by birds. Theophrastus reports how the bearing olive can be grafted on the wild olive, for which the Greeks had a separate name, kotinos. In his Enquiry into Plants (2.1.2–4) he states that the olive can be propagated from a piece of the trunk, the root, a twig, or a stake.


According to Pliny the Elder, a vine, a fig tree, and an olive tree grew in the middle of the Roman Forum; the olive was planted to provide shade (the garden plot was recreated in the 20th century). The Roman poet Horace mentions it in reference to his own diet, which he describes as very simple: "As for me, olives, endives, and smooth mallows provide sustenance." Lord Monboddo comments on the olive in 1779 as one of the foods preferred by the ancients and as one of the most perfect foods.
Vitruvius describes of the use of charred olive wood in tying together walls and foundations in his De Architectura:
The thickness of the wall should, in my opinion, be such that armed men meeting on top of it may pass one another without interference. In the thickness there should be set a very close succession of ties made of charred olive wood, binding the two faces of the wall together like pins, to give it lasting endurance. For that is a material which neither decay, nor the weather, nor time can harm, but even though buried in the earth or set in the water it keeps sound and useful forever. And so not only city walls but substructures in general and all walls that require a thickness like that of a city wall, will be long in falling to decay if tied in this manner.


Olives were one of the main elements in ancient Israelite cuisine. Olive oil was used for not only food and cooking, but also lighting, sacrificial offerings, ointment, and anointment for priestly or royal office. The olive tree is one of the first plants mentioned in the Hebrew Bible (the Christian Old Testament), and one of the most significant. An olive branch (or leaf, depending on translation) was brought back to Noah by a dove to demonstrate that the flood was over (Book of Genesis 8:11).
The olive is listed in Deuteronomy 8:8 as one of the seven species that are noteworthy products of the Land of Israel. According to the Halakha, the Jewish law mandatory for all Jews, the olive is one of the seven species that require the recitation of me'eyn shalosh after they are consumed. Olive oil is also the most recommended and best possible oil for the lighting of the Shabbat candles.
The Mount of Olives, east of Jerusalem, is mentioned several times in the New Testament. The Allegory of the Olive Tree in St. Paul's Epistle to the Romans refers to the scattering and gathering of Israel. It compares the Israelites to a tame olive tree and the Gentiles to a wild olive branch. The olive tree itself, as well as olive oil and olives, play an important role in the Bible.


The olive tree and olive oil are mentioned seven times in the Quran, and the olive is praised as a precious fruit. Olive tree and olive oil health benefits have been propounded in prophetic medicine. Muhammad is reported to have said: "Take oil of olive and massage with it – it is a blessed tree" (Sunan al-Darimi, 69:103). Olives are substitutes for dates (if not available) during Ramadan fasting, and olive tree leaves are used as incense in some Muslim Mediterranean countries.


The Great Seal of the United States first used in 1782 depicts an eagle clutching an olive branch in one of its talons, indicating the power of peace.


The Flag of the United Nations adopted in 1946 is a world map with two olive branches.


An olive tree in Mouriscas, Abrantes, Portugal, (Oliveira do Mouchão) is one of the oldest known olive trees still alive to this day, with an estimated age of 3,350 years, planted approximately at the beginning of the Atlantic Bronze Age.
An olive tree on the island of Brijuni in Croatia has a radiocarbon dating age of about 1,600 years. It still gives fruit (about 30 kg or 66 lb per year), which is made into olive oil.
An olive tree in west Athens, named "Plato's Olive Tree", is thought to be a remnant of the grove where Plato's Academy was situated, making it an estimated 2,400 years old. The tree comprised a cavernous trunk from which a few branches were still sprouting in 1975, when a traffic accident caused a bus to uproot it. Following that, the trunk was preserved and displayed in the nearby Agricultural University of Athens. In 2013, it was reported that the remaining part of the trunk was uprooted and stolen, allegedly to serve as firewood.
The age of an olive tree in Crete, the Finix Olive, is claimed to be over 2,000 years old; this estimate is based on archaeological evidence around the tree.
The olive tree of Vouves in Crete has an age estimated between 2,000 and 4,000 years.
An olive tree called Farga d'Arió in Ulldecona, Catalonia, Spain, has been estimated (with laser-perimetry methods) to date back to 314 AD, which would mean that it was planted when Constantine the Great was Roman emperor.
Some Italian olive trees are believed to date back to Ancient Rome (8th century BC to 5th century AD), although identifying progenitor trees in ancient sources is difficult. Several other trees of about 1,000 years old are within the same garden. The 15th-century trees of Olivo della Linza, at Alliste in the Province of Lecce in Apulia on the Italian mainland, were noted by Bishop Ludovico de Pennis during his pastoral visit to the Diocese of Nardò-Gallipoli in 1452.
The village of Bcheale, Lebanon, claims to have the oldest olive trees in the world (4000 BC for the oldest), but no scientific study supports these claims. Other trees in the towns of Amioun appear to be at least 1,500 years old.
Several trees in the Garden of Gethsemane (from the Hebrew words gat shemanim or olive press) in Jerusalem are claimed to date back to the time of Jesus. A study conducted by the National Research Council of Italy in 2012 used carbon dating on older parts of the trunks of three trees from Gethsemane and came up with the dates of 1092, 1166, and 1198 AD, while DNA tests show that the trees were originally planted from the same parent plant. According to molecular analysis, the tested trees showed the same allelic profile at all microsatellite loci analyzed which furthermore may indicate attempt to keep the lineage of an older species intact. However, Bernabei writes, "All the tree trunks are hollow inside so that the central, older wood is missing . . . In the end, only three from a total of eight olive trees could be successfully dated. The dated ancient olive trees do not, however, allow any hypothesis to be made with regard to the age of the remaining five giant olive trees." Babcox concludes, "The roots of the eight oldest trees are possibly much older. Visiting guides to the garden often state that they are two thousand years old."
The 2,000-year-old Bidni olive trees on Malta, which have been confirmed through carbon dating, have been protected since 1933 and are listed in UNESCO's Database of National Cultural Heritage Laws. In 2011, after recognising their historical and landscape value, and in recognition of the fact that "only 20 trees remain from 40 at the beginning of the 20th century", Maltese authorities declared the ancient Bidni olive grove at Bidnija as a Tree Protected Area.


The olive tree, Olea europaea, has been cultivated for olive oil, fine wood, olive leaf, ornamental reasons, and the olive fruit. About 90% of all harvested olives are turned into oil, while about 10% are used as table olives. The olive is one of the "trinity" or "triad" of basic ingredients in Mediterranean cuisine, the other two being wheat for bread, pasta, and couscous; and the grape for wine.


Olive oil is a liquid fat obtained from olives, produced by pressing whole olives and extracting the oil. It is commonly used in cooking, for frying foods or as a salad dressing. It is also used in cosmetics, pharmaceuticals, and soaps, and as a fuel for traditional oil lamps, and has additional uses in some religions. Spain accounts for almost half of global olive oil production; other major producers are Portugal, Italy, Tunisia, Greece and Turkey. Per capita consumption is highest in Greece, followed by Italy and Spain.
The composition of olive oil varies with the cultivar, altitude, time of harvest and extraction process. It consists mainly of oleic acid (up to 83%), with smaller amounts of other fatty acids including linoleic acid (up to 21%) and palmitic acid (up to 20%). Extra virgin olive oil is required to have no more than 0.8% free acidity and is considered to have favorable flavor characteristics.


Table olives are classified by the International Olive Council (IOC) into three groups according to the degree of ripeness achieved before harvesting:
Green olives are picked when they have obtained full size, while unripe; they are usually shades of green to yellow and contain the bitter phytochemical oleuropein.
Semi-ripe or turning-colour olives are picked at the beginning of the ripening cycle, when the colour has begun to change from green to multicolour shades of red to brown. Only the skin is coloured, as the flesh of the fruit lacks pigmentation at this stage, unlike that of ripe olives.
Black olives or ripe olives are picked at full maturity when fully ripe, displaying colours of purple, brown or black. To leach the oleuropein from olives, commercial producers use lye, which neutralizes the bitterness of oleuropein, producing a mild flavour and soft texture characteristic of California black olives sold in cans. Such olives are typically preserved in brine and sterilized under high heat during the canning process.


Raw or fresh olives are naturally very bitter; to make them palatable, olives must be cured and fermented, thereby removing oleuropein, a bitter phenolic compound that can reach levels of 14% of dry matter in young olives. In addition to oleuropein, other phenolic compounds render freshly picked olives unpalatable and must also be removed or lowered in quantity through curing and fermentation. Generally speaking, phenolics reach their peak in young fruit and are converted as the fruit matures. Once ripening occurs, the levels of phenolics sharply decline through their conversion to other organic products which render some cultivars edible immediately. One example of an edible olive native to the island of Thasos is the throubes black olive, which becomes edible when allowed to ripen in the sun, shrivel, and fall from the tree.
The curing process may take from a few days with lye, to a few months with brine or salt packing. With the exception of California style and salt-cured olives, all methods of curing involve a major fermentation involving bacteria and yeast that is of equal importance to the final table olive product. Traditional cures, using the natural microflora on the fruit to induce fermentation, lead to two important outcomes: the leaching out and breakdown of oleuropein and other unpalatable phenolic compounds, and the generation of favourable metabolites from bacteria and yeast, such as organic acids, probiotics, glycerol, and esters, which affect the sensory properties of the final table olives. Mixed bacterial/yeast olive fermentations may have probiotic qualities. Lactic acid is the most important metabolite, as it lowers the pH, acting as a natural preservative against the growth of unwanted pathogenic species. The result is table olives which can be stored without refrigeration. Fermentations dominated by lactic acid bacteria are, therefore, the most suitable method of curing olives. Yeast-dominated fermentations produce a different suite of metabolites which provide poorer preservation, so they are corrected with an acid such as citric acid in the final processing stage to provide microbial stability.
The many types of preparations for table olives depend on local tastes and traditions. The most important commercial examples are listed below.
Lebanese or Phoenician fermentation
Applied to green, semiripe, or ripe olives. Olives are soaked in salt water for 24-48 hours. Then they are slightly crushed with a rock to hasten the fermentation process. The olives are stored for a period of up to a year in a container with salt water, lemon juice, lemon peels, laurel and olive leaves, and rosemary. Some recipes may contain white vinegar or olive oil.
Spanish or Sevillian fermentation
Most commonly applied to green olive preparation, around 60% of all the world's table olives are produced with this method. Olives are soaked in lye (dilute NaOH, 2–4%) for 8–10 hours to hydrolyse the oleuropein. They are usually considered "treated" when the lye has penetrated two-thirds of the way into the fruit. They are then washed once or several times in water to remove the caustic solution and transferred to fermenting vessels full of brine at typical concentrations of 8–12% NaCl. The brine is changed on a regular basis to help remove the phenolic compounds.
Fermentation is carried out by the natural microbiota present on the olives that survive the lye treatment process. Many organisms are involved, usually reflecting the local conditions or terroir of the olives. During a typical fermentation gram-negative enterobacteria flourish in small numbers at first but are rapidly outgrown by lactic acid bacteria species such as Leuconostoc mesenteroides, Lactobacillus plantarum, Lactobacillus brevis and Pediococcus damnosus. These bacteria produce lactic acid to help lower the pH of the brine and therefore stabilize the product against unwanted pathogenic species. A diversity of yeasts then accumulate in sufficient numbers to help complete the fermentation alongside the lactic acid bacteria. Yeasts commonly mentioned include the teleomorphs Pichia anomala, Pichia membranifaciens, Debaryomyces hansenii and Kluyveromyces marxianus.
Once fermented, the olives are placed in fresh brine and acid corrected, to be ready for market.
Sicilian or Greek fermentation
Applied to green, semiripe and ripe olives, they are almost identical to the Spanish type fermentation process, but the lye treatment process is skipped and the olives are placed directly in fermentation vessels full of brine (8–12% NaCl). The brine is changed on a regular basis to help remove the phenolic compounds. As the caustic treatment is avoided, lactic acid bacteria are only present in similar numbers to yeast and appear to be outdone by the abundant yeasts found on untreated olives. As very little acid is produced by the yeast fermentation, lactic, acetic, or citric acid is often added to the fermentation stage to stabilize the process.
Picholine or directly-brined fermentation
Applied to green, semi-ripe, or ripe olives, they are soaked in lye typically for longer periods than Spanish style (e.g. 10–72 hours) until the solution has penetrated three-quarters of the way into the fruit. They are then washed and immediately brined and acid corrected with citric acid to achieve microbial stability. Fermentation still occurs carried out by acidogenic yeast and bacteria but is more subdued than other methods. The brine is changed on a regular basis to help remove the phenolic compounds, and a series of progressively stronger concentrations of salt are added until the product is fully stabilized and ready to be eaten.
Water-cured fermentation
Applied to green, semi-ripe, or ripe olives, these are soaked in water or weak brine and this solution is changed on a daily basis for 10–14 days. The oleuropein is naturally dissolved and leached into the water and removed during a continual soak-wash cycle. Fermentation takes place during the water treatment stage and involves a mixed yeast/bacteria ecosystem. Sometimes, the olives are lightly cracked with a blunt instrument to trigger fermentation and speed up the fermentation process. Once debittered, the olives are brined to concentrations of 8–12% NaCl and acid corrected and are then ready to eat.
Salt-cured fermentation
Applied only to ripe olives, since it is only a light fermentation. They are usually produced in Morocco, Turkey, and other eastern Mediterranean countries. Once picked, the olives are vigorously washed and packed in alternating layers with salt. The high concentration of salt draws the moisture out of olives, dehydrating and shriveling them until they look somewhat analogous to a raisin. Once packed in salt, fermentation is minimal and only initiated by the most halophilic yeast species such as Debaryomyces hansenii. Once cured, they are sold in their natural state without any additives. So-called oil-cured olives are cured in salt, and then soaked in oil.
California or artificial ripening
Applied to green and semi-ripe olives, they are placed in lye and soaked. Upon their removal, they are washed in water injected with compressed air, without fermentation. This process is repeated several times until both oxygen and lye have soaked through to the pit. The repeated, saturated exposure to air oxidises the skin and flesh of the fruit, turning it black in an artificial process that mimics natural ripening. Once fully oxidised or "blackened", they are brined and acid corrected and are then ready for eating.


Olive wood is very hard and is prized for its durability, colour, high combustion temperature, and interesting grain patterns. Because of the commercial importance of the fruit, slow growth, and relatively small size of the tree, olive wood and its products are relatively expensive. Common uses of the wood include: kitchen utensils, carved wooden bowls, cutting boards, fine furniture, and decorative items. The yellow or light greenish-brown wood is often finely veined with a darker tint; being very hard and close-grained, it is valued by woodworkers.


In modern landscape design olive trees are frequently used as ornamental features for their distinctively gnarled trunks and "evergreen" silvery gray foliage.


The earliest evidence for the domestication of olives comes from the Chalcolithic period archaeological site of Teleilat el Ghassul in modern Jordan. Farmers in ancient times believed that olive trees would not grow well if planted more than a certain distance from the sea; Theophrastus gives 300 stadia (55.6 km or 34.5 mi) as the limit. Modern experience does not always confirm this, and, though showing a preference for the coast, they have long been grown further inland in some areas with suitable climates, particularly in the southwestern Mediterranean (Iberia and northwest Africa) where winters are mild. An article on olive tree cultivation in Spain is brought down in Ibn al-'Awwam's 12th-century agricultural work, Book on Agriculture.
Olives are cultivated in many regions of the world with Mediterranean climates, such as South Africa, Chile, Peru, Pakistan, Australia, Oregon, and California, and in areas with temperate climates such as New Zealand. They are also grown in the Córdoba Province, Argentina, which has a temperate climate with rainy summers and dry winters.


Olive trees show a marked preference for calcareous soils, flourishing best on limestone slopes and crags, and coastal climate conditions. They grow in any light soil, even on clay if well drained, but in rich soils, they are predisposed to disease and produce poor quality oil. (This was noted by Pliny the Elder.) Olives like hot weather and sunny positions without any shade, while temperatures below −10 °C (14 °F) may injure even a mature tree. They tolerate drought well because of their sturdy and extensive root systems. Olive trees can remain productive for centuries as long as they are pruned correctly and regularly.
Only a handful of olive varieties can be used to cross-pollinate. 'Pendolino' olive trees are partially self-fertile, but pollenizers are needed for a large fruit crop. Other compatible olive tree pollinators include 'Leccino' and 'Maurino'. 'Pendolino' olive trees are used extensively as pollinizers in large olive tree groves.
Olives are propagated by various methods. The preferred ways are cuttings and layers; the tree roots easily in favourable soil and throws up suckers from the stump when cut down. However, yields from trees grown from suckers or seeds are poor; they must be budded or grafted onto other specimens to do well. Branches of various thickness cut into lengths around 1 m (3+1⁄2 ft) planted deeply in manured ground soon vegetate. Shorter pieces are sometimes laid horizontally in shallow trenches and, when covered with a few centimetres of soil, rapidly throw up sucker-like shoots. In Greece, grafting the cultivated tree on the wild tree is a common practice. In Italy, embryonic buds, which form small swellings on the stems, are carefully excised and planted under the soil surface, where they soon form a vigorous shoot.
The olive is also sometimes grown from seed. To facilitate germination, the oily pericarp is first softened by slight rotting, or soaked in hot water or in an alkaline solution.
In situations where extreme cold has damaged or killed the olive tree, the rootstock can survive and produce new shoots which in turn become new trees. In this way, olive trees can regenerate themselves. In Tuscany in 1985, a very severe frost destroyed many productive and aged olive trees and ruined many farmers' livelihoods. However, new shoots appeared in the spring and, once the dead wood was removed, became the basis for new fruit-producing trees.
Olives grow very slowly, and over many years, the trunk can attain a considerable diameter. A. P. de Candolle recorded one exceeding 10 m (33 ft) in girth. The trees rarely exceed 15 m (50 ft) in height and are generally confined to much more limited dimensions by frequent pruning. Olives are very hardy and are resistant to disease and fire. Its root system is robust and capable of regenerating the tree even if the above-ground structure is destroyed.
The crop from old trees is sometimes enormous, but they seldom bear well two years in succession, and in many cases, a large harvest occurs every sixth or seventh season. Where the olive is carefully cultivated, as in Liguria, Languedoc, and Provence, the trees are regularly pruned. The pruning preserves the flower-bearing shoots of the preceding year, while keeping the tree low enough to allow the easy gathering of the fruit. The spaces between the trees are regularly fertilized.


Various pathologies can affect olives. The most serious pest is the olive fruit fly (Dacus oleae or Bactrocera oleae) which lays its eggs in the olive most commonly just before it becomes ripe in the autumn. The region surrounding the puncture rots, becomes brown, and takes a bitter taste, making the olive unfit for eating or for oil. For controlling the pest, the practice has been to spray with insecticides (organophosphates, e.g. dimethoate). Classic organic methods have been applied such as trapping, applying the bacterium Bacillus thuringiensis, and spraying with kaolin.  Such methods are obligatory for organic olives.
A fungus, Cycloconium oleaginum, can infect the trees for several successive seasons, causing great damage to plantations. A species of bacterium, Pseudomonas savastanoi pv. oleae, induces tumour growth in the shoots. Certain lepidopterous caterpillars feed on the leaves and flowers. Xylella fastidiosa bacteria, which can also infect citrus fruit and vines, has attacked olive trees in Apulia, southern Italy, causing olive quick decline syndrome (OQDS). The main vector is Philaenus spumarius (meadow spittlebug).
A pest which spreads through olive trees is the black scale bug, a small black scale insect that resembles a small black spot. They attach themselves firmly to olive trees and reduce the quality of the fruit; their main predators are wasps. The curculio beetle eats the edges of leaves, leaving sawtooth damage.
Rabbits eat the bark of olive trees and can do considerable damage, especially to young trees. If the bark is removed around the entire circumference of a tree, it is likely to die. Voles and mice also do damage by eating the roots of olives. At the northern edge of their cultivation zone, for instance in northern Italy, or southern France and Switzerland, olive trees suffer occasionally from frost. Gales and long-continued rains during the gathering season also cause damage.


Since its first domestication, O. europaea has been spreading back to the wild from planted groves. Its original wild populations in southern Europe have been largely swamped by feral plants.
In some other parts of the world where it has been introduced, most notably South Australia, the olive has become a major woody weed that displaces native vegetation. In South Australia, its seeds are spread by the introduced red fox and by many bird species, including the European starling and the native emu, into woodlands, where they germinate and eventually form a dense canopy that prevents regeneration of native trees. As the climate of South Australia is very dry and bushfire prone, the oil-rich feral olive tree substantially increases the fire hazard of native sclerophyll woodlands.


Olives are one of the most extensively cultivated fruit crops in the world. In 2011, about 9.6 million hectares (24 million acres) were planted with olive trees, which is more than twice the amount of land devoted to apples, bananas, or mangoes. Only coconut trees and oil palms command more space. Cultivation area tripled from 2.6 to 7.95 million hectares (6.4 to 19.6 million acres) between 1960 and 1998 and reached a peak of 10 million hectares (25 million acres) in 2008. The 10 most-producing countries, according to the Food and Agriculture Organization, are all located in the Mediterranean region and produce 95% of the world's olives.


One hundred grams of cured green olives provide 146 calories, are a rich source of vitamin E (25% of the Daily Value, DV), and contain a large amount of sodium (104% DV); other nutrients are insignificant. Green olives are 75% water, 15% fat, 4% carbohydrates and 1% protein (table).


The polyphenol composition of olive fruits varies during fruit ripening and during processing by fermentation when olives are immersed whole in brine or crushed to produce oil. In raw fruit, total polyphenol contents, as measured by the Folin method, are 117 mg/100 g in black olives and 161 mg/100 g in green olives, compared to 55 and 21 mg/100 g for extra virgin and virgin olive oil, respectively. Olive fruit contains several types of polyphenols, mainly tyrosols, phenolic acids, flavonols and flavones, and for black olives, anthocyanins. The main bitter flavor of olives before curing results from oleuropein and its aglycone which total in content, respectively, 72 and 82 mg/100 g in black olives, and 56 and 59 mg/100 g in green olives.
During the crushing, kneading and extraction of olive fruit to obtain olive oil, oleuropein, demethyloleuropein and ligstroside are hydrolyzed by endogenous beta-glucosidases to form aldehydes, dialdehydes, and aldehydic aglycones. Polyphenol content also varies with olive cultivar and the manner of presentation, with plain olives having higher contents than those that are pitted or stuffed.


Olive tree pollen is extremely allergenic, with an OPALS allergy scale rating of 10 out of 10. Olea europaea is primarily wind-pollinated and its light, buoyant pollen is a strong trigger for asthma. One popular variety, "Swan Hill", is widely sold as an "allergy-free" olive tree; however, this variety does bloom and produce allergenic pollen.


Olearia arborescens, also known as common tree daisy is a common shrub or small tree of New Zealand. It grows in lowland to alpine scrubland in the North Island from East Cape southwards, and throughout the South and Stewart Islands.
The leaves of the plant are wide, oval-shaped, wavy and toothed, and are greyish underneath. O. arborescens produces white bunched flowers in spring to summer.


Olearia avicenniifolia, known commonly as mountain akeake, is a flowering plant in the family Asteraceae. It is endemic to New Zealand where it is found on the southern coastlines of the South Island and on Stewart Island. It is classified as Not Threatened.


Mountain akeake is a small, bushy shrub or tree that grows up to 6 metres tall and 3 metres wide. It has thin, papery bark and angular branchlets covered in white tomentum. Leaves are oblong-lanceolate in shape. They are dark green in colour with a downy, white underside. Leaf length varies between 5–10 cm long and 3–5 cm wide.
Flowers are clustered and daisy-like with white rays and purple central disks. They emerge between November and February and have a sweet scent. Flowers are about 5 centimetres wide and carried in clusters of three to ten. The flowers develop into fluffy seeds.


It was first described in 1946 by Raoul as Shawia avicenniifolia and transferred to the Olearia genus by Joseph Hooker in 1864.


Olearia paniculata, commonly called akiraho, is a species of shrub or tree in the family Asteraceae, found only in New Zealand. The tree can grow to 6 metres high, and has yellow-green, oval-shaped leaves, with white undersides and wavy margins.
Olearia paniculata produces clusters of daisy flowers in late autumn.


Olearia paniculata is a small evergreen tree that is indigenous and commonly found in both the North and South Islands of New Zealand. It has reddish twigs bearing very smooth and wavy-edged oval green leaves that are white underneath and twigs that are grooved on the top surface and angular in cross-section. It can grow up to about 6 meters tall. Olearia paniculata branchlets are grooved, sharp-cornered, very short and grow up to short lengths such as 2-4 centimeters. Flowers are small, white, and in dense clusters. Petiole of the akiraho plant which exists as a stalk that attaches the leaf blade to the stem which grows up to 5 millimeters long. It also has a white thin appressed white to buff tomentum below. Olearia paniculata also has a sweet smell to it and is looked at by many people as used for creating hedges. The genus is named after Johann Gottfried Olearius, a 17th-century German scholar and author of Specimen Florae Hallensis. Paniculata, on the other hand, means “Small sprayed”. Olearia paniculata leaf margins can be flat or strongly wavy.


Olearia paniculata is endemic to both the North and South Islands of New Zealand.


Olearia paniculata is a small evergreen tree that is indigenous and commonly found in both the North and South Islands of New Zealand. It can be found in the East Cape to south Canterbury. It is not native to Taranaki but can be seen growing rapidly as a hedge plant.


Olearia paniculata is most likely to be found in non-local seed sources. The habitat includes a large amount of grass (c. 50% cover), with c. 3-m-tall plantings in clumps up to 5 m2. Akiraho is also commonly found around other shrubs, herbs, and ferns that are common on the forest floor. It is suited to dry soils and windy places which make it common in coastal areas. This species is not found in the naturally regenerating mature forest. Prefers full sun to partial shade with well-draining soil. Coastal conditions and dry windy situations, so it does not drown and kill the plant. It also tolerates moderate frosts but does not tolerate saturated soils.


Olearia paniculata produces clusters of daisy flowers in late autumn. Akiraho is a plant that grows well after autumn rains as the soil is preferably soft and moist and warm which allows it to become well established before the winter season.  Akiraho goes into the flowering stage between the months of March and May and goes into the fruiting stage between the months of April and July.


Olearia paniculata has no known pests or diseases. Goats, cattle and sheep will sometimes eat the leaves.


Olearia paniculata the evergreen shrub or tree, does need water to grow but not too much water. With the leaf density of the evergreen plant, it can be important in promoting durability, water conservation, and protection from predators. The kinds of soil Olearia paniculata prefer is the soil after the autumn season rains as during this stage the soil is moist and warm which is just good for the species because it allows it to establish. It is important to plant Olearia paniculata into slightly raised beds of well-cultivated soil. Because this will create drainage that provides near-surface roots with aerated soil in which to grow. Like all other young plants, they require thorough watering during dry times over the first two or four years mulching which helps to better conserve moisture and suppress weeds. Often when Olearia paniculata is mixed with coarse sand, compost, or organic material it improves the soil's health and moisture structure. When planting Akiraho it is essential to ensure the root ball is saturated and when digging the hole make sure it is twice the diameter of the root ball and watered once being planted.


Akiraho plant has sweet-smelling flowers. Pruning is not normally required unless it is being planted as a hedge, when it will require regular trimming.


Oligoria is a genus of butterflies in the family Hesperiidae. It contains only one species, the twin-spot skipper (Oligoria maculata) which is found in the United States along the coast of North Carolina south through Florida and west along the Gulf Coast to east Texas. Strays can be found as far north as Pennsylvania, Maryland and New Jersey.
The wingspan is 35–42 mm. The wings are rounded and brown black. There are four transparent spots on the upperside of the forewings. The underside of the hindwings has a pale red-brown overlay and three white spots. Adults are on wing from April to September in two or possibly three generations per year. They feed on flower nectar of various plant species, including Pontederia species.
The larvae feed on various Poaceae species.


Olla v-nigrum is a species in the family Coccinellidae ("lady beetles"), in the suborder Polyphaga. The species is known generally as the ashy gray lady beetle. The distribution range of Olla v-nigrum includes Central America, North America, and Oceania. It is usually gray or pale tan with small black spots on its elytra and thorax. However, a variation can resemble Chilocorus orbus. This form is black with two red spots on the wing covers and has white on the edge of the prothorax.


Olneya tesota is a perennial flowering tree of the family Fabaceae, legumes (peas, beans, etc.), which is commonly known as ironwood, desert ironwood, or palo fierro in Spanish. It is the only species in the monotypic genus Olneya. This tree is part of the western Sonoran Desert complex in the Southwestern United States.


The desert ironwood grows as a bush or tree, reaching heights of about 10 metres (33 feet) and average trunk diameters of about 60 centimetres (24 inches). Exceptionally, in larger protected washes it can reach greater height and a more massive trunk.
In younger trees, the bark is gray, shiny, and smooth; in older trees the bark is broken open. The tree is evergreen, but can lose its leaves if temperatures fall below 2 °C (36 °F). In continual drought conditions the leaves will be lost.
The leaves are bluish-green and pinnately compound. They are arranged on a petiole, 15 cm (6 in) long, with 6–9 leaflets (or variously up to 15, with 7 opposite and one terminal), each measuring 0.7 to 2.5 cm (1⁄4 to 1 in). At the base of each pinnate leaf petiole grow two thorns, each about 1 cm (3⁄8 in) long.
Bloom time occurs in late April/May to June. Flowers are of 5 unequal petals, in colors of medium purple, magenta-red, or white to pale pink. Seedpods are 5–8 cm (2–3 in) long and light reddish brown when seedpods have ripened.
Two other species, Parkinsonia florida (blue palo verde) and Acacia constricta (catclaw acacia), have similar light red/brownish seedpods. Catclaw acacia's seedpods are shorter and J-shaped.


The pleasant-tasting sap is consumed by bees and hummingbirds. The silky-flycatcher or phainopepla pose a problem, for when they consume mistletoe berries and excrete them in the cracks of Olneya tesota, the mistletoe will parasitize its host.


The seeds can be eaten by first being roasted.
Olneya ironwood is very hard and heavy. Its density is greater than water and thus sinks; it does not float downstream in washes and must be moved by current motion.
Due to its considerable hardness, processing desert ironwood is difficult. Final treatment of the wood with solutions can also be difficult because of its high density. As a result, mass processing of this wood is difficult, and most of its commercial usages are artisanal, such as durable wooden sculptures as well as knife handles.


Ironwood Forest National Monument in south-central Arizona is named for O. tesota.


Olsynium douglasii is a species of flowering plant in the iris family (Iridaceae). Common names include Douglas' olsynium, Douglas' grasswidow, grass-widow, blue-eyed grass, purple-eyed-grass, and satin flower, It is native to western North America, from southern British Columbia south to northern California, and east to northwest Utah. It is the only species in the genus Olsynium in North America, the remaining 11 species being from South America. It was formerly treated in the related genus Sisyrinchium.
It is a herbaceous bulbiferous perennial growing 10–40 cm (3.9–15.7 in) tall. The leaves are slender, linear, 10–30 cm (3+7⁄8–11+3⁄4 in) long and 1.5–3 mm broad. The flowers are bell-shaped to star-shaped, 15–25 mm long, with six purple tepals.
There are two varieties:
Olsynium douglasii var. douglasii. Coastal western North America. Flower filaments with a narrow base
Olsynium douglasii var. inflatum. Interior western North America. Flower filaments with an inflated base
Olsynium douglasii has won the Royal Horticultural Society’s Award of Garden Merit.


Omalotheca sylvatica, also called woodland arctic cudweed, is a species of plant from family Asteraceae found in Eastern United States and British Columbia, on the lawns, roads, and in the forests. For the plant to grow, the roads shall not be in shade, and lowly grassed.


Aside from growing on the roads and lawns of the United States, it is also common in Adirondack Mountains.


Omocestus viridulus, known in the British Isles as the common green grasshopper, is a Palearctic species in the subfamily Gomphocerinae.


Omocestus viridulus are usually green all over, but some may have brown coloration on the sides. In Scandinavia, they are usually green or light brown. The males do not have any red coloring on the abdomen and possess a noticeably long ovipositor, characteristics that help distinguish it from the similar species O. rufipes and O. haemorrhoidalis. The eyes of this species may be brown or yellow. The typical body length is 17–20 millimetres (0.67–0.79 in). They possess a strongly darkened region of the hind wing.


Omocestus viridulus typically lives in moderately wet regions around Europe except north of the Arctic Circle, and it is distributed widely over Britain. Its range extends east as far as Siberia and Mongolia. Their preferred habitat consists of areas with longer grass.


This species prefers to feed on the more common, abundant grass species and this may promote greater diversity of vegetation. O. viridulus feeds on grass from the genera Dactylis, Agrostis, Anthoxanthum, Lolium and Holcus. The life cycle begins with the females laying their clutch of eggs in the top layer of soil or near the root of the grass stalks. The young are called nymphs and emerge the next April. These nymphs resemble miniature versions of the adults with immature wings. After about a month of moulting their exoskeleton several times, they mature into adults with working wings. There is one generation of O. viridulus a year, and they are usually seen between the months of April and October.


Compared to other grasshopper species, the reproductive fitness of O. viridulus tends to be less affected by temperature changes. It has been found that for female O. viridulus, the number of eggs in each pod, and the mass of eggs were not adversely affected by temperature. In the wild, the males find the females quickly and mate, and the females refrain from singing until they lay at least one cluster of eggs. If the male fails to mate with a female, he will sing before trying again.


Songs are produced by a process called stridulation in which the hind leg and wing are rubbed together. Calling songs are used by these grasshoppers in order to attract and find a mate. Although most of the singing is done by the males, females that are ready to mate may also sing in response. The females also use stridulation to produce their songs. The male normally sings only one calling song in one place before moving on to another spot to try calling again. However, occasionally they may call more than once in the same spot. Ticking is another sound that is produced when the male flicks the hind part of its back leg against one of its fore wings (the process is called a tibial flick). In the courtship process, the frequency of these tibial flicks does not follow a regular pattern and is highly variable between 5 and 15 ticks repeated roughly every 1 to 2 seconds. Geographical variation is also present in the mating song of this species. In Spain, where this grasshopper exists as the subspecies O. viridulus kaesteneri, the song tends to be shorter than in other regions. When singing to a female, one of the hind legs is moved at a much wider angle than the other and this generates most of the sound. The songs are characterised by crescendos that make up a significant part of the song. The songs start quietly and increase until it reaches the greatest intensity, and then dies out. The males usually follow up their calling songs with a succession of loud syllables and then try to mate with the female. When the male is calling to a female, there is a greater amplitude of movement for the hind leg facing the female. Males call when a female is close by, and these songs last about 45–60 seconds each with breaks of 10–15 s in between. Various studies have been performed on the songs of O. viridulus. Heinrich et al. demonstrated that singing in both males and females can be induced with the injection of acetylcholine. A study by Eiríksson revealed that the males of this species can use their songs most efficiently based on how frequently they sing and how they time their songs, as it is important that the males minimize the overlap of their songs with the females' song so that they can find each other. If the female sings at the same time as the male, the male might not hear the female's song. The males try to minimize this overlap in songs because he must be able to hear the female’s song in order to locate her.


Omophoita cyanipennis, the eight-spotted flea beetle, is a species of flea beetle in the family Chrysomelidae. It is found in the Caribbean Sea, Central America, and North America.


These two subspecies belong to the species Omophoita cyanipennis:
Omophoita cyanipennis cyanipennis (Fabricius, 1798)
Omophoita cyanipennis octomaculata (Crotch, 1873)


Oncometopia orbona, the broad-headed sharpshooter, is a species of sharpshooter in the family Cicadellidae.


Oncopeltus fasciatus, known as the large milkweed bug, is a medium-sized hemipteran (true bug) of the family Lygaeidae. It is distributed throughout North America, from Central America through Mexico and the Caribbean to southern areas in Canada. Costa Rica represents this insect's southern limit. It inhabits disturbed areas, roadsides, and open pastures. Due to this widespread geographic distribution, this insect exhibits varying life history trade-offs depending on the population location, including differences in wing length and other traits based on location.


This insect is often used as a model organism and reared for laboratory experiments due to  being easy to rear and handle, short developmental time, few instars, and  high fecundity. The phylogenetic placement of O. fasciatus is ideal to use as an outgroup to make comparisons to more derived holometabolous insects, acting as a valuable organism for the study of evolutionary patterns.


Oncosiphon pilulifer, also known as globe chamomile and stinknet, is a flowering plant in the daisy family (Asteraceae) native to South Africa and Lesotho. It is considered invasive in some parts of North America.


Synonyms include Matricaria globifera because it was previously in the Matricaria genus, and Pentzia globifera, named for 18th century Swedish botanist Carolus Johannes Pentz.
The common name "stinknet" reflects the plant's strong odor.


Globe chamomile is a straggly, branching annual plant with a strong smell, growing up to 2 ft (60 cm) tall. The bipinnate or tripinnate leaves have a fleshy midrib which widens at the base. The globular flowers are borne in paniculate flower heads. There are no ray florets and the disc florets are yellow.


Onobrychis viciifolia, also known as O. sativa or common sainfoin (IPA: ['sænfɔɪn]) has been an important forage legume in temperate regions until the 1950s. During the Green Revolution it was replaced by high yielding alfalfa and clover species. Due to its anthelmintic properties the common sainfoin is a natural alternative to drugs to control nematode parasitism in the guts of small ruminants. This is the main reason why O. viciifolia came back to the scientific agenda during the last years.


The genus Onobrychis comprises 54 different species of which O. viciifolia is of greatest agronomic importance. Two different agricultural types of O. viciifolia are known. The single-cut type is characterized by a vegetative regrowth after cutting and its origin is in Europe. A generative regrowth after cutting is typical for the second or the double-cut type. Originated in the Middle East the double-cut type grows larger than the single-cut type. Compared to other forage legumes both types are weak in competition and their regrowth after mowing is considered to be low. Also the yields of common sainfoin are significantly lower than those of alfalfa and clover.
In terms of symbiotic nitrogen fixation from the atmosphere, common sainfoin is not as specific as other legumes. A relatively broad range of rhizobia genera is able to colonize the roots of O. viciifolia.
The common sainfoin is an open pollinating plant, mainly pollinated by nectar feeding insects. Therefore, O. viciifolia is a promising crop to enhance biodiversity within agro-ecosystems. This pollination biology leads to certain difficulties in breeding programs resulting in a low number of registered cultivars.
The leaves of common sainfoin contain high levels of condensed tannins. This content can be more than five times higher than in clover species or alfalfa	.


An animal diet containing common sainfoin is able to reduce nematode (e.g. Haemonchus contortus) parasitism in ruminant’s guts. Due to the high levels of condensed tannins, the fecundity of nematodes and the number of their eggs in the ruminant’s digestive system are reduced. Especially in goat and sheep production systems feeding of O. viciifolia is a promising alternative or complement to synthetic drugs.
Besides these anthelmintic properties diets containing common sainfoin can lead to increasing daily weight gains of small ruminants. Also milk quantity and quality of these animals are not negatively affected by O. viciifolia intake. Furthermore, various studies showed that the voluntary intake of sainfoin was comparable or even higher than the intake of alfalfa or clover species.


To reach high levels of condensed tannins common sainfoin should be sown in pure culture. Due to its low competitiveness, weed infestation has to be controlled, especially in the first year. Normally fertilizer applications are not needed to reach satisfying yields. Nevertheless, slurry or phosphate applications can promote initial growth. Pests and diseases are almost never a serious problem.
Frost and drought tolerance of common sainfoin is higher than in other forage legumes such as alfalfa or different clover species. In contrast O. viciifolia is much more intolerant to water logging than other forage legumes. Therefore, clayey soils with a bad drainage should be avoided. Also acidic soils are not appropriate for the cultivation of common sainfoin.
Seedbed preparation and sowing procedure are done in a similar manner and with the same machinery as for cereal cultivation. Around 800 seeds per square meter should be sown on a weed free seedbed between spring and late summer. In the year of establishment common sainfoin can be cut twice a year. Afterwards up to four cuts per growing season are possible. Careful mowing is important to minimize disintegration losses. Common sainfoin can be stored and fed to animals in the form of hay, pellets or silage.


Onoclea sensibilis, the sensitive fern, also known as the bead fern, is a coarse-textured, medium to large-sized deciduous perennial fern. The name comes from its sensitivity to frost, the fronds dying quickly when first touched by it. It is sometimes treated as the only species in Onoclea, but some authors do not consider the genus monotypic.


The sterile and fertile fronds of Onoclea sensibilis have independent stalks originating from the same rhizome, quite different from other ferns. The bright, yellow-green trophophylls (sterile fronds) are deeply pinnatifid and are typically borne at intervals along the creeping rhizome.  The sterile fronds are deciduous with trophopods, swollen bases, that  serve as over winter storage organs.  The sterile fronds of O. var. sensibilis have a length of 1–1.3 m (3–4 ft) with 5–11 pinnae, leaf pairs, evenly spaced along the stipe.  O. var. interrupta Maxim. fronds are shorter, 20–50 cm (8–20 in) long, with fewer pinnae, only 5–8 pairs.
The sporophylls (fertile fronds) are smaller, 20–45 cm (8–18 in) in length, non-green at maturity and have very narrow pinnae.  They are persistent, standing 2–3 years.  The sori comprise clusters of sporangia (spore cases) 2–4 mm (1/10–1/6 in) in diameter, like beads, on upright fertile fronds, hence the common name Bead fern.
Sori are typically bilaterally symmetrical, though leaf forms have been observed with pinnae fertile only on a single side of the rachis. This form, named O. sensibilis L. F. hemiphyllodes (Kiss & Kümmerle, 1926) and a second, O. sensibilis L. F. obtusilobata having flat pinnules (not curled or bead shaped), were deemed to be variations not meriting taxonomic recognition (J. M. Beitel et al. 1981).
The fiddleheads have a pale reddish color.


The spermatogenesis process spans formation of spermatogenous cells to the release of spore. In homosporous ferns, like O. sensibilis L., developing spermatids are surrounded by two different walls at specific development stages, as opposed to a single wall reported in other species. Other differences include a delayed formation of the osmiophilic crest and during sperm release the cap cell removes intact, as opposed to forming a pore or collapsing altogether.  Spores are monolete with the antheridium, or sporangium, containing either 32 or 64 sperm spores, usually being 64.  Regardless of the number, the capsule's volume remains nearly the same.
The mechanics of spore release and its timing are controlled by springtime humidity.  The small fertile  margins, that in live-form held spore in tightly rolled structures, maintain their dry, leathery shape over winter.  These pinnules respond to spring's higher humidity by opening, releasing their spore into the air.  Subsequent gametophytes are unisexual in early development, favoring cross-fertilization, later becoming bisexual to ensure species survival.


The genus  Onoclea was cast by Carl Linnaeus in 1751, separating from the fern's prior association with the Angiopteris genus. The binominal name, Onoclea sensibilis, was published in his 1753 Species Plantarum.


Onoclea sensibilis has two geographically disjunctive varieties. Onoclea sensibilis var. sensibilis is native to North America; Canada's central and eastern regions and the United States' north, central and eastern regions.  Onoclea sensibilis var. interrupta Maximowicz (aka Maxim.) is native to Southeast Siberia, Japan and China.  The varietal difference is their ultimate height, O. var. interrupta Maxim. only reaching half the height of its sister.


Onoclea sensibilis' name was descriptive. Onoclea comes from the Greek onos, meaning a vessel, and kleio, meaning to close, describing the closely rolled sori on its fertile fronds. Its species, from the Late Latin sensibilis, means sensitive, describing its high sensitivity to autumn's first frost and to drought.


Onoclea sensibilis is native to Northern Hemisphere temperate regions; the Russian Far East, China and Eastern Asia, and a wide native distribution in Northern America.  It ranges from Newfoundland south to Florida and west to Texas, the Rocky Mountains, North and South Dakota, Quebec, and Manitoba.
It has become naturalized in western Europe and New Zealand.
Onoclea sensibilis can be found at elevations from sea level up to 1,500 metres (4,900 ft) in fresh water habitats, not brackish, as its spore germination ceases at salt (NaCl) levels ≥ 0.6%, moderately saline water and higher.
Onoclea sensibilis grows best in moist shaded or partially shaded areas, dwelling in a variety of swamp and wood habitats: wet meadows, thickets and bogs, as well as stream and riverbanks and roadside ditches.  It tolerates extremely wet soils, appearing in soggy ground or at the very edge of water in shade or sun.  The plant can tolerate dryer conditions in shade.
It prefers acidic (pH<6.8), loose, sandy to loam, limestone-based soils.


The Onoclea sensibilis plant has remained essentially unchanged over millions of years. A fifty-seven million year old fossil of Paleocene epoch flora shows specimens virtually identical to modern samples.  It has a life cycle featuring alternation of generations, sexual and asexual reproduction; its sporophyte generation matures in autumn, casts its spores in the spring and the gametophyte generation follows. Sporophytes require 5-10 years of growth before reaching their mature fern height.
Sensitive ferns propagate by both spore dispersion and rhizome growth.  Its growth clusters attract local fauna where small wildlife find habitat, deer bed upon its dense mat and in winter wild turkeys use the fertile spore stalks as a secondary food source.  They can become aggressive and a nuisance if established near preferable vegetation. The University of Maine's Cooperative Extension: Maine Wild Blueberries classifies the sensitive fern as a herbaceous broadleaf weed.
Its deciduous fronds do not tolerate freezing temperatures, however, the plant survives USDA hardiness zones 4-8, or minimum temperatures of -20 °C to -15 °C (-4 °F to 5 °F) having the Royal Horticultural Society's H6 rating.  Winter survival is enhanced if the dried frond petiole bases are left intact.
Nutrient beneficial ectotrophic mycorrhizal associations may occur in Onoclea sensibilis, Pteridium aquilinum and Adiantum pedatum located in oak and hickory forests.
Onoclea sensibilis is a wetland indicator, listed as a Facultative Wetland Hydrophyte in the 2013 (US) National Wetland Plant List due to its observed affinity for wetter soils.
Opinion is mixed regarding the species' tolerance to disturbance of its growing environment. In one forest setting, a decade long decline was noticed following even single-cut tree felling operations.  In other settings sensitive ferns appear opportunistic, disturbance not being a problem. They spread to form colonies, often the first species to inhabit disturbed areas.


Onoclea sensibilis hosts insects, fungi, bacteria and even a parasitic vine, Cuscuta gronovii (scaldweed), that can overgrow and constrict it.


Insects feeding upon the Onoclea sensibilis target both its leaves and rhizome roots.  Amphorophora ampullata fern aphids, Chirosia gleniensis fern miners and the larvae of sawflies Hemitaxonus dubitatus and Stromboceros delicatulus feed on its leaves. Larvae of  moth species Phlogophora iris (olive angle shades, pictured), Callopistria cordata (silver-spotted fern moth) and  Papaipema inquaesita (Sensitive Fern Borer) are known to feed on both stems and rhizomes.


Parasitic fungi include Ceratobasidium anceps, causing frond and stem necrosis; Ceratobasidium cornigerum, covering stems with saprophyte growths;  and Uredinopsis mirabilis, a distinct rust species unique to the Sensitive Fern.  Invasive fungi like Taphrina filicina, Taphrina hiratsukae and Phyllactinia corylea, synonym Phyllactinia guttata can infect leaves, causing blisters or white powdery mildew.
Fungi can develop beneath beech trees, where aphid honeydew secretions accumulate; these strictly epiphyllous honeydew fungi, Sclerotiomyces colchicus and Scorias spongiosa (Schwein.) Fr., have been recorded on Onoclea sensibilis, where their sooty mold buildup impairs leaf function.


Onoclea sensibilis can host Burkholderia plantarii which causes stem lesions. B. plantarii is a pathogen of bacterial seedling blight in rice.  In a multi-year study the weedy presence of O. sensibilis at rice paddy fields and a means to convey the bacterium (rainfall runoff) implicated it as the source of bacterial blight outbreaks when paired with enabling environmental conditions.


Onoclea sensibilis has two internally-synthesized chemical defenses against insects.  Ingesting any part of the plant introduces  thiaminase enzymes and phytoecdysteroid hormones which can disrupt an insect's molting cycle, preventing its full development.


Its human toxicity is not well defined; no specific warnings for Onoclea sensibilis have been found.  Its summaries, however, frequently include precautionary statements that ferns, in general, may contain natural carcinogens and/or the enzyme thiaminase, the latter being dangerous in high concentration.  Historically, some Native American peoples have consumed Onoclea sensibilis without apparent distress; see Food uses in this article.


Onoclea sensibilis has limited value for food use, considered a famine food by some and reserved for times of scarcity.  Cooking heat eliminates its thiaminase content.  The Iroquois treated Onoclea sensibilis as an early springtime vegetable, prepared like spinach, the fiddleheads cooked and "seasoned with salt, pepper or butter" (Waugh, 1916). After removing the "brown scales" (sori), leaves were processed likewise.
Its young shoots have been sold as delicacies in Asian markets.


It is cultivated as an ornamental plant in traditional and native plant gardens, and in natural landscaping and habitat restoration projects.  It has gained the Royal Horticultural Society's Award of Garden Merit. Gardeners employ rhizome division and are aided by spore harvesting guides.  Its decomposing fronds make an effective mulch, suppressing undergrowth. Plantings can become aggressive, weedy if not sited properly.


Historically, Native American peoples used Onoclea sensibilis for oral and topical indigenous treatments.


Onopordum acanthium (cotton thistle, Scotch (or Scottish) thistle, not to be confused with Cirsium vulgare - spear thistle, which is also known as Scotch or Scottish thistle and is the national flower of Scotland.  Spear thistle is native to Britain and is common and widespread - Cotton thistle is non-native) is a flowering plant in the family Asteraceae. It is native to Europe and Western Asia from the Iberian Peninsula east to Kazakhstan, and north to central Scandinavia, and widely naturalised elsewhere, with especially large populations present in the United States and Australia. It is a vigorous biennial plant with coarse, spiny leaves and conspicuous spiny-winged stems.


It is a biennial plant, producing a large rosette of spiny leaves the first year. The plants typically germinate in the autumn after the first rains and exist as rosettes throughout the first year, forming a stout, fleshy taproot that may extend down 30 cm (12 in) or more for a food reserve.
In the second year, the plant can grow to as much as 3 m (9.8 ft) tall with a width of up to 1.5 m (4 ft 11 in). The leaves are 10–50 cm (3.9–19.7 in) wide, alternate, spiny, and often covered with white woolly hairs with the lower surface more densely covered than the upper. The leaves are deeply lobed with long, stiff spines along the margins. Fine hairs give the plant a greyish appearance. The massive main stem may be 10 cm (3.9 in) wide at the base and branched in the upper part. Each stem has a vertical row of broad, spiny wings (conspicuous ribbon-like leafy material), typically 2–3 cm (0.79–1.18 in)m wide, extending to the base of the flower head.
The flowers are globe shaped, 2–6 cm (0.79–2.36 in) in diameter, from dark pink to lavender, and are produced in the summer. The flower buds form first at the tip of the stem and later at the tip of the axillary branches. They appear singly or in groups of two or three on branch tips. The plants are androgynous, with both pistil and stamens, and sit above numerous, long, stiff, spine-tipped bracts, all pointing outwards, the lower ones wider apart and pointing downwards. After flowering, the ovary starts swelling and forms about 8,400 to 40,000 seeds per plant.


Cotton thistle is native to Europe and Asia. The plant prefers habitats with dry summers, such as the Mediterranean region, growing best in sandy clay and calcareous soils which are rich in ammonium salts. It grows in ruderal places, as well as dry pastures and disturbed fields. Its preferred habitats are natural areas, disturbed sites, roadsides, fields, and especially sites with fertile soils, agricultural areas, range/grasslands, riparian zones, scrub/shrublands valleys and plains along with water courses. Temperature and moisture, rather than soil nutrient concentrations, determine the ecological performance of Onopordum species.
In Europe, the plant tends to colonise disturbed pastures. In its native range, cotton thistle is considered a weak competitor that needs regeneration gaps to develop and maintain stands; populations tend to retreat when disturbance ceases. The plant has been widely introduced at mid-latitudes across much of North America.
Scotch thistle can spread rapidly. For example, it was first found in Utah in 1963. By 1981, it covered approximately 6070 hectares in 17 counties. Eight years later, it had spread to cover more than 22,540 hectares in 22 counties.


Onopordum acanthium reproduces only by seeds. Most seeds germinate in autumn after the first rains, but some seeds can germinate year round under favourable moisture and temperature conditions. Seeds that germinate in late autumn become biennials. But when they germinate earlier, they can behave as annuals. Buried seed can remain viable in the soil seed bank for at least seven years and possibly for up to twenty years or more. Yearly seed production and seed dormancy are highly variable depending on environmental conditions. The slender and smooth achenes are about 3 mm long and are brown with gray markings. They are tipped with a pappus of slender bristles. Mainly locally dispersed by wind, or more widely by humans, birds, wildlife, livestock or streams, the seeds are sensitive to light and only germinate when close to the surface. Seedlings will emerge from soil depths up to 4.5 cm, with 0.5 cm being optimal. While some seeds will germinate in the dark, studies indicate that most germination occurs with alternating light/dark cycles, with 8 hours being the optimal day length.
The leaves of cotton thistle provide food for the caterpillars of some Lepidoptera, such as the thistle ermine (Myelois circumvoluta).


Three subspecies are accepted:
Onopordum acanthium subsp. acanthium. Most of the species' range.
Onopordum acanthium subsp. gautieri (Rouy) Franco. France, Spain.
Onopordum acanthium subsp. parnassicum (Boiss. & Heldr.) Nyman. Greece.
The genus botanical name is derived from the Ancient Greek words όνος (ónos=donkey), πέρδω (pérdo=to fart), and άκανθος (ácanthos=thorn), meaning 'donkey fart thorny food'.
The common name of cotton thistle derives from the cotton-like hairs on the leaves. Other names include Scots thistle or Scottish thistle, heraldic thistle and woolly thistle. The name Scots thistle comes from the flower used as the national emblem of Scotland. Despite its name, it has nothing to do with the actual thistle that is used as the emblem of Scotland, which is the Cirsium vulgare.


It is grown as an ornamental plant for its bold foliage and large flowers. It has been used to treat cancers and ulcers and to diminish discharges of mucous membranes. A recent study of a crude extract from the leaves of the plant demonstrated activity against glioblastoma, a type of very malignant brain tumor. The receptacle was eaten in earlier times like an artichoke. The cottony hairs on the stem have been occasionally collected to stuff pillows. Oil from the seeds has been used for burning and cooking.
Thistles produce abundant nectar for pollinators and provide seeds and floss for birds such as the goldfinch. Large-flowered tall thistles in particular provide considerable nectar.


In the late 19th century, it was introduced to temperate regions of North America, South America, and Australia as an ornamental plant, and is now considered a major agricultural and wildland noxious weed. It has been recorded from nearly 50 countries. It is difficult to eradicate because of its drought resistance. It can spread rapidly and eventually dense stands prohibit foraging by livestock. Infestations of cotton thistle often start in disturbed areas such as roadways, campsites, burned areas, and ditch banks. The weed adapts best to areas along rivers and streams, but can be a serious problem in pastures, grain fields and range areas. A single plant is imposing enough, but an entire colony can ruin a pasture or destroy a park or campsite, sometimes forming tall, dense, impenetrable stands. This issue is often amplified by the prolific thorns found on this species. Besides creating an impenetrable barrier to humans and animals, the plant nearly eliminates forage use by livestock and some mammal species such as deer and elk.
In the United States, known infestations include most of the Pacific Northwest along with Utah, Colorado, New Mexico, Wyoming, Nebraska, and South Dakota. On western rangeland, infestations directly result in significant economic losses for ranchers. It is also widespread in Australia and New Zealand. In Australia it commonly hybridises with the related invasive Onopordum illyricum.


Mechanical
Small infestations may be physically removed or cut a few centimetres below the soil surface ensuring that no leaves remain attached to prevent regrowth. Mowing during early flowering will not kill the plant but will reduce seed production. Repeated treatments may be required because populations typically exhibit a wide range of developmental stages among individual plants. Slashing should be done prior to flowering since seed may mature in the seed head after cutting. Plants should not be mowed following seed set, as this increases chances for seed dispersal.
Chemical
Because of their shorter life cycle, cotton thistle plants can be effectively treated with herbicides. All herbicide treatments should be applied at the rosette stage of the plant. Generally, herbicide applications would be in early spring or autumn. One of the primary difficulties in chemical control of cotton thistles is their ability to germinate nearly year round. From autumn to spring a range of plant sizes can be found which may result in variable success from chemical control. Herbicides are very effective on seedlings and young rosettes, but control becomes more variable with increasing plant age. Onopordum spp. seeds may persist for several years in the soil. Buried seed may persist for up to twenty years, and reinfestation is likely without yearly management. Therefore, several years of re-treatment may be necessary. Picloram, dicamba, 2,4-D, dicamba + 2,4,-D, and metsulfuron are effective for controlling cotton thistle. Clopyralid is more selective for controlling plants in the family Asteraceae, but will also injure or kill legumes.
Biological
There are no biological control agents that have been specifically released for cotton thistle control in the United States. A thistle head weevil Rhinocyllus conicus that feeds on Carduus pycnocephalus has also been shown to feed on cotton thistle. This insect was the object of imprudent biological control introduction, and it became an invasive species that has threatened endangered native thistles in North America (Strong 1997). Establishment of this thistle head weevil as a biological control agent for cotton thistle has been unsuccessful in the Pacific Northwest. A thistle crown weevil (Trichosirocalus horridus) that feeds on musk, bull, plumeless, Italian, and creeping thistles will also feed on cotton thistle. In Australia, this insect has been shown to kill cotton thistle rosettes. The related Trichosirocalus briese is also being tested as a control agent. The Australian painted lady butterfly has been known to use this invasive species as a host plant, but the larvae do not do enough damage to the plant for this butterfly to be used as biological control agent.
In Australia, a total of seven insects have been released to control cotton thistle. Two of the seven released insects are weevils, including Larinus latus which feeds on the seeds, and Lixus cardui, which bores in the stems.
Integrated management
A combination of methods (IPM) is often more effective than any single method. An integrated pest management plan deals with prevention as well as control. Eradication of weed species is often not a practical goal, but in many cases reducing infestation to manageable levels is an achievable objective. Seed bank longevity is a major factor in managing cotton thistles. Re-establishing competitive perennial grasses and monitoring infested areas on a yearly basis is critical. Herbicides can successfully be used for reducing thistle populations and giving grasses a competitive advantage, but they cannot be used as a stand-alone solution. These techniques must be linked with good grazing practices in rangeland areas. Otherwise, the thistles will recolonize and rapidly replenish the seed bank to pre-control levels.


The red-winged starling (Onychognathus morio) is a bird of the starling family Sturnidae native to eastern Africa from  Ethiopia to the Cape in South Africa. An omnivorous, generalist species, it prefers cliffs and mountainous areas for nesting, and has moved into cities and towns due to similarity to its original habitat.


In 1760 the French zoologist Mathurin Jacques Brisson included a description of the red-winged starling in his Ornithologie based on a specimen collected from the Cape of Good Hope in South Africa. He used the French name Le merle du Cap de Bonne Espérance and the Latin Merula Capitis Bonae Spei. Although Brisson coined Latin names, these do not conform to the binomial system and are not recognised by the International Commission on Zoological Nomenclature. When in 1766 the Swedish naturalist Carl Linnaeus updated his Systema Naturae for the twelfth edition, he added 240 species that had been previously described by Brisson. One of these was the red-winged starling. Linnaeus included a brief description, coined the binomial name Turdus morio and cited Brisson's work. The specific name morio or morion is Latin for "dark brown stone" or "black quartz". This species is now placed in the genus Onychognathus that was introduced by the German physician and ornithologist Gustav Hartlaub in 1849.
Two subspecies are recognised:
O. m. rueppellii (Verreaux, J, 1856) – south Sudan to central Ethiopia and north Kenya
O. m. morio (Linnaeus, 1766) – Uganda and Kenya to Botswana and south South Africa


The male of this 27–30-centimetre (11–12 in) long starling has mainly iridescent black plumage, with chestnut flight feathers, which are particularly noticeable in flight. The female has an ash-grey head and upper breast. The juvenile resembles the male, but is less glossy than the adults, and has brown rather than dark red eyes. The Ethiopian subspecies  O. m. rupellii is longer-tailed than the nominate form and intergrades with it.
This species has a number of whistled calls, but the most familiar is the contact call, cher-leeeoo.
This starling may be confused with other similar starling species, such as its sister species the pale-winged starling. The difference between the two is that the red-winged has rufous primaries while the pale-winged has whitish primaries edged with orange. The pale-winged has a bright red or orange eye, while the red-winged's is dark, almost black. Only the female of the red-winged has a grey head.


The range runs down eastern Africa from Ethiopia to the Cape, Kwa-Zulu Natal and Gauteng in South Africa. This species has a wide habitat tolerance. It may be found in forest, savannah, grassland, wetlands, fynbos, farmlands and commercial plantations, as well as urban centres. It is now common in many urban areas, due to the similarity between the structure of tall buildings and houses as nest sites with the cliffs of its original habitat. It may also nest in residential areas, breeding in roofs and apertures and up house eaves.


Like other starlings, the red-winged starling is an omnivore, taking a wide range of seeds, berries, nectar from plants such as Aloe and Schotia brachypetala, and invertebrates, such as the beetle species Pachnoda sinuata.  They may take nestlings and adults of certain bird species, such as the African palm swift. It will also scavenge on carrion and human food scrap.
The red-winged starling will obviously only perch on plant structures that will be able to support its weight; therefore when taking nectar it will choose certain species with strong, robust racemes with easily accessible flowers, such as that of Aloe ferox and Aloe marlothii, and not Aloe arborescens. Large flowers that can support the bird's weight, such as that of Strelitzia nicolai and certain Protea species, are also chosen.
Fruit species that this species may feed on include figs, such as the sycamore fig and others, marulas, date palm fruit, berries from species such as wild olive Olea europaea subsp. cuspidata and Euphorbia, and commercial fruit such as apples, grapes, citruses and others.
In rural areas, red-winged starlings are often spotted perching on livestock and game, such as cattle, klipspringers and giraffes, a trait shared by the pale-winged starling, and may take insects and ectoparasites such as ticks, much in the manner of oxpeckers.


The red-winged starling is territorial, aggressive and intolerant when nesting, and will attack other species, including domestic animals and humans. When not breeding, red-winged starlings are highly gregarious and will associate with other members of their species in large flocks.
This starling is a cliff nester, breeding on rocky cliffs, outcrops and gorges. The red-winged starling builds a lined nest of grass and twigs, and with a mud base, on a natural or structural ledge. It lays two to four, usually three, blue eggs, spotted with red-brown. The female incubates the eggs for 13–14 days, with another 22–28 days to fledge. This starling is commonly double-brooded. It may be parasitised by the great spotted cuckoo.


The red-winged starling is not endangered and can be a pest in some areas, raiding orchards and attacking people that wander too close to their nests.


Onychogomphus forcipatus, the small pincertail or green-eyed hook-tailed dragonfly, is a species of dragonflies belonging to the family Gomphidae.