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Lignum nephriticum (Latin for "kidney wood") is a traditional diuretic that was derived from the wood of two tree species, the narra (Pterocarpus indicus) and the Mexican kidneywood (Eysenhardtia polystachya). The wood is capable of turning the color of water it comes in contact with into beautiful opalescent hues that change depending on light and angle, the earliest known record of the phenomenon of fluorescence. Due to this strange property, it became well known in Europe from the 16th to the early 18th-century. Cups made from lignum nephriticum were given as gifts to royalty. Water drunk from such cups, as well as imported powders and extracts from lignum nephriticum, were thought to have great medicinal properties.

The lignum nephriticum derived from Mexican kidneywood was known as the coatli, coatl, or cuatl ("snake water") or tlapalezpatli ("blood-tincture medicine") in the Nahuatl language. It was traditionally used by the Aztec people as a diuretic prior to European contact. Similarly, the lignum nephriticum cups made from narra wood were part of the native industry of the Philippines before the arrival of the Spanish. The cups were manufactured in southern Luzon, particularly in the Naga region. The name of which was derived from the abundance of the narra trees, which was known as naga in the Bikol language (literally "serpent" or "dragon").

Botanical sexism is a term coined by horticulturist Tom Ogren to describe the planting of male plants instead of female plants of certain dioecious species including: willows, poplars, aspens, ashes, silver maples, pistache, mulberry, pepper tree and other woody plants such as junipers, yew pines, fern pines, wax myrtles, alpine currants, plum yews, and yews According to Ogren, pollen allergies have been amplified due to the planting in urban areas of male clones which increases the amount of pollen in the air. Male plants are commonly used in urban areas because plants with female flowers produce fruits and flowers that litter the landscape. The planting of more female plants would decrease the overall amount of pollen since they do not produce pollen and remove pollen from the air for pollination. The theory has existed since at least the 2000s. Biological sexism is used in the Ogren Plant Allergy Scale (OPALS), which has been adopted by the United States Department of Agriculture. Botanical sexism has found some scientific acceptance as a reason for increased allergies and asthma; however, other scientists have also been critical of it, stating that it only applies to certain trees and is not as widespread as Ogren alleges.

Tendril perversion, often referred to in context as simply perversion, is a geometric phenomenon found in helical structures such as plant tendrils, in which a helical structure forms that is divided into two sections of opposite chirality, with a transition between the two in the middle. A similar phenomenon can often be observed in kinked helical cables such as telephone handset cords.

The phenomenon was known to Charles Darwin, who wrote in 1865,

A tendril ... invariably becomes twisted in one part in one direction, and in another part in the opposite direction... This curious and symmetrical structure has been noticed by several botanists, but has not been sufficiently explained.

The term "tendril perversion" was coined by Goriely and Tabor in 1998 based on the word perversion found in the 19th Century science literature. "Perversion" is a transition from one chirality to another and was known to James Clerk Maxwell, who attributed it to the topologist J. B. Listing.

Tendril perversion can be viewed as an example of spontaneous symmetry breaking, in which the strained structure of the tendril adopts a configuration of minimum energy while preserving zero overall twist.

Tendril perversion has been studied both experimentally and theoretically. Gerbode et al. have made experimental studies of the coiling of cucumber tendrils. A detailed study of a simple model of the physics of tendril perversion was made by MacMillen and Goriely in the early 2000s. Liu et al. showed in 2014 that "the transition from a helical to a hemihelical shape, as well as the number of perversions, depends on the height to width ratio of the strip's cross-section."

Generalized tendril perversions were put forward by Silva et al., to include perversions that can be intrinsically produced in elastic filaments, leading to a multiplicity of geometries and dynamical properties.

Ayahuasca is a South American (pan-Amazonian) psychoactive brew used both socially and as ceremonial spiritual medicine among the indigenous peoples of the Amazon basin. It is a psychedelic and entheogenic brew commonly made out of the Banisteriopsis caapi vine, the Psychotria viridis shrub or a substitute, and possibly other ingredients. A chemically similar preparation, sometimes called "pharmahuasca", can be prepared using N,N-Dimethyltryptamine (DMT) and a pharmaceutical monoamine oxidase inhibitor (MAOI), such as isocarboxazid. B. caapi contains several alkaloids that act as MAOIs, which are required for DMT to be orally active. Ayahuasca is prepared in a tea that, when consumed, causes an altered state of consciousness or "high", including visual hallucinations and altered perceptions of reality.

The other required ingredient is a plant that contains the primary psychoactive, DMT. This is usually the shrub P. viridis, but Diplopterys cabrerana may be used as a substitute. Other plant ingredients often or occasionally used in the production of ayahuasca include Justicia pectoralis, one of the Brugmansia (especially Brugmansia insignis and Brugmansia versicolor, or a hybrid breed) or Datura species, and mapacho (Nicotiana rustica).

Ensete ventricosum, commonly known as enset or ensete, Ethiopian banana, Abyssinian banana, and false banana, is an herbaceous species of flowering plant in the banana family Musaceae. The domesticated form of the plant is only cultivated in Ethiopia, where it provides the staple food for approximately 20 million people. The name Ensete ventricosum was first published in 1948 in the Kew Bulletin, 1947, p. 101. Its synonyms include Musa arnoldiana De Wild., Musa ventricosa Welw. and Musa ensete J.F.Gmel. In its wild form, it is native to the eastern edge of the Great African Plateau, extending northwards from South Africa through Mozambique, Zimbabwe, Malawi, Kenya, Uganda and Tanzania to Ethiopia, and west to the Congo, being found in high rainfall forests on mountains, and along forested ravines and streams.

An albino redwood is a redwood tree which is unable to produce chlorophyll, and has white needles instead of the normal green. It survives by obtaining sugar through the connections between its roots and those of neighboring normal redwood(s), usually the parent tree from whose base it has sprouted. Sap exchange through roots is a general phenomenon among redwoods. About 400 are known. They can be found in Henry Cowell Redwoods State Park, Humboldt Redwoods State Park, San Francisco Botanical Garden, Huddart Park, and The Santa Lucia Preserve, with eleven trees in the first. The exact locations are not publicized to protect the rare trees. They reach a maximum height of about 20 m (66 ft). Other conifers lack the ability to graft their roots, so 'albino' mutants of other species do not survive to become sizable trees.

The trees were important to Native Americans and were recorded in their legends. For example, the Pomo people used them in their cleansing ceremonies.

Albino redwoods are generally regarded as parasitic plants, but as of 2016 one researcher speculates that they are supported by other trees for their role in storing toxic heavy metals. Albinos apparently accumulate more metals than normal trees because of defective stomata, which cause them to lose more water through transpiration, forcing them to compensate by taking up more water through their roots.

Six phenotypes of albino redwood have been classified: white, bright yellow, cellular virescent green, pale green, mottled and nonchimeric variegated. Such mutants can be either basal (growing from a burl at the base of a tree) or aerial (branching off from a tree above the ground). The bright yellow form is exclusively aerial and is thought to be associated with excess xanthophyll production. The pale green form lacks just one specific type of chlorophyll and is almost always basal. Cellular virescent green trees have a few normal cells (whose abundance may vary over time) interspersed among the mutant cells.

Ten cases are known of chimeric redwoods that have a mosaic of albino and normal tissues. Only a single chimeric redwood is known to produce cones. Formerly threatened by the Sonoma–Marin Area Rail Transit rail development, it has since been replanted.

Three phenotypes of chimeric redwoods have been noted: sectorial, mericlinal and periclinal. In sectorial mutants, albino cells are present vertically through all cell layers, with genotype boundaries usually parallel to the stem. Mericlinal trees have mutant cells in only some cell layers and have an unstable phenotype; the albino cells can disappear and reappear in successive years. A periclinal chimera has both mutant and normal cells distributed horizontally across the tip of each bud propagating at equal rates, leading to a very stable phenotype.

The Hungry Tree is a tree in the grounds of the King's Inns in Dublin, Republic of Ireland. An otherwise unremarkable specimen of the London plane, it has become known for having partially consumed a nearby park bench. It has become a tourist attraction and is frequently photographed. The Hungry Tree was the subject of a campaign by Green Party politician Ciarán Cuffe to ensure its preservation.

Romanesco broccoli (also known as Roman cauliflower, Broccolo Romanesco, Romanesque cauliflower, or simply Romanesco) is an edible flower bud of the species Brassica oleracea. First documented in Italy in the 16th century, it is chartreuse in color, and has a form naturally approximating a fractal. When compared to a traditional cauliflower, it has a firmer texture and delicate, nutty flavor.