Chamaenerion is a genus of flowering plants in the family Onagraceae. It is sometimes included in the genus Epilobium. Members of the genus may be called willowherbs, or fireweeds, based on a common name used for C. angustifolium. They are upright herbaceous perennials, growing from a woody base or from rhizomes, with racemes of purple to pink flowers. All species are found in the northern hemisphere. Most occur in moist habitats. Chamaenerion species are upright herbaceous perennials with either unbranched stems or, much less slightly branched stems, they either grow from rhizomes. The leaves are spirally arranged on the stems and are narrow ovate; the inflorescence is a simple or branched raceme. Individual flowers have four petals that are rose-purple to pink white; the petals are free at the base rather than united in a floral tube, as in Epilobium. The lower petals are narrower than the upper ones, making the flower radially unsymmetric. There are eight more-or-less sized stamens, a long, four-lobed style.
The fruit is a long, four-chambered capsule that splits to reveal the many seeds. The seeds have a tuft of hairs at one end; the taxonomy of Chamaenerion is complicated. There are two issues: should the genus be separated from Epilobium, if so, what should its name be, Chamaenerion or Chamerion? Nomenclatural issues were reviewed by Alexander N. Sennikov in 2011. Although pre-Linnaean authors had used the name Chamaenerion, which may have originated as early as 1561, in 1753 Carl Linnaeus preferred Epilobium. Chamaenerion is derived from the Greek chamai, meaning "low", "near the ground", nerion, the oleander, Nerium oleander; some authors continued to use Chamaenerion, but this name was not published legitimately under the International Code of Nomenclature for algae and plants until Jean-François Séguier did so in 1754. It was assumed by some authors that Séguier's name was a superfluous replacement for Linnaeus' Epilobium, but Sennikov argues that a strict application of the ICN shows that it was legitimate.
Ludwig K. G. Pfeiffer in 1873 used Chamaenerion in a more restricted sense than Linnaeus' Epilobium, designating Epilobium angustifolium L. as the type species. Thus the correct name for a genus separated from Epilobium and including Linnaeus' Epilobium angustifolium is Chamaenerion. In 1818, Constantine Samuel Rafinesque used the name Chamerion, suggesting it as either a subgenus or genus. Rafinesque had his own "rules" of botanical nomenclature, regarding it as appropriate to shorten generic names. However, his name was not acceptable under the ICN until published by Josef Ludwig Holub in 1972. Holub designated Epilobium amenum Raf; as this is now included in Chamaenerion angustifolium, Chamaenerion has precedence over Chamerion. Sennikov's conclusion has been accepted by many sources since the publication of his paper, including Tropicos, GRIN Taxonomy for Plants, the Onagraceae website of the Smithsonian Museum of Natural History, the Global Biodiversity Information Facility; some sources published earlier that split up Epilobium use the name Chamerion, including the Flora of China.
In 1994, a molecular phylogenetic study of 22 taxa of Epilobium, broadly defined, included three species assigned by some botanists to a separate genus, by others to a section within Epilobium. The results showed that Epilobium and Chamaenerion were sister taxa: The finding that Chamaenerion is sister to the rest of the genus contradicted a hypothesis that it was a specialized subgroup of Epilobium. Chamaenerion can be distinguished from Epilobium by features which include: having leaves spirally arranged rather than opposite. A 2007 monograph on the classification of the family Onagraceae accepted the separation of Epilobium and Chamaenerion, dividing Chamaenerion into two sections and Rosmarinifolium. Differences between the species in the two sections are summarized in the table below; as of February 2012, eight species were recognized, in two sections: Chamaenerion sect. Chamaenerion Chamaenerion angustifolium Scop. – Eurasia and North America Chamaenerion conspersum Kitam. - Himalayas, China Chamaenerion latifolium Th.
Fr. & Lange – Eurasia and North America Chamaenerion speciosum Lodd. Ex Steud. – Himalayas, China Chamaenerion sect. Rosmarinifolium Chamaenerion colchicum Steinb. – Caucasus, Western Asia Chamaenerion dodonaei Schur – Eurasia Chamaenerion fleischeri Fritsch – European Alps Chamaenerion stevenii Sosn. Ex Grossh. – Caucasus, Western Asia Chamaenerion is native to the northern hemisphere. Six of the eight species are native to Eurasia; this contrasts with most members of the family Onagraceae, which are native only to the western hemisphere. Most species are found in moist, rocky areas. C. angustifolium is the exception. Its English name, reflects its regular occurrence in areas recovering from wildfires, to which it may be adapted. Chamaenerion species are used as food plants by the caterpillars of certain Lepidoptera species, including: Double-striped pug, recorded on fireweed The gothic, recorded on
The tropics are the region of the Earth surrounding the Equator. They are delimited in latitude by The Tropic of Cancer in the Northern Hemisphere at 23°26′12.4″ N and the Tropic of Capricorn in the Southern Hemisphere at 23°26′12.4″ S. The tropics are referred to as the tropical zone and the torrid zone; the tropics include all the areas on the Earth where the Sun contacts a point directly overhead at least once during the solar year - thus the latitude of the tropics is equal to the angle of the Earth's axial tilt. The tropics are distinguished from the other climatic and biomatic regions of Earth, which are the middle latitudes and the polar regions on either side of the equatorial zone; the tropics contain 36 % of the Earth's landmass. As of 2014, the region is home to 40% of the world population, this figure is projected to reach 50% by the late 2030s. "Tropical" is sometimes used in a general sense for a tropical climate to mean warm to hot and moist year-round with the sense of lush vegetation.
Many tropical areas have a wet season. The wet season, rainy season or green season is the time of year, ranging from one or more months, when most of the average annual rainfall in a region falls. Areas with wet seasons are disseminated across portions of the subtropics. Under the Köppen climate classification, for tropical climates, a wet-season month is defined as a month where average precipitation is 60 millimetres or more. Tropical rainforests technically do not have dry or wet seasons, since their rainfall is distributed through the year; some areas with pronounced rainy seasons see a break in rainfall during mid-season when the intertropical convergence zone or monsoon trough moves poleward of their location during the middle of the warm season. When the wet season occurs during the warm season, or summer, precipitation falls during the late afternoon and early evening hours; the wet season is a time when air quality improves, freshwater quality improves and vegetation grows leading to crop yields late in the season.
Floods cause rivers to overflow their banks, some animals to retreat to higher ground. Soil nutrients erosion increases; the incidence of malaria increases in areas. Animals have survival strategies for the wetter regime; the previous dry season leads to food shortages into the wet season, as the crops have yet to mature. However, regions within the tropics may well not have a tropical climate. Under the Köppen climate classification, much of the area within the geographical tropics is classed not as "tropical" but as "dry", including the Sahara Desert, the Atacama Desert and Australian Outback. There are alpine tundra and snow-capped peaks, including Mauna Kea, Mount Kilimanjaro, the Andes as far south as the northernmost parts of Chile and Argentina. Tropical plants and animals are those species native to the tropics. Tropical ecosystems may consist of tropical rainforests, seasonal tropical forests, dry forests, spiny forests and other habitat types. There are significant areas of biodiversity, species endemism present in rainforests and seasonal forests.
Some examples of important biodiversity and high endemism ecosystems are El Yunque National Forest in Puerto Rico, Costa Rican and Nicaraguan rainforests, Amazon Rainforest territories of several South American countries, Madagascar dry deciduous forests, the Waterberg Biosphere of South Africa, eastern Madagascar rainforests. The soils of tropical forests are low in nutrient content, making them quite vulnerable to slash-and-burn deforestation techniques, which are sometimes an element of shifting cultivation agricultural systems. In biogeography, the tropics are divided into Neotropics. Together, they are sometimes referred to as the Pantropic; the Neotropical region should not be confused with the ecozone of the same name. "Tropicality" refers to the geographic imagery that many people outside the tropics have of that region. The idea of tropicality gained renewed interest in modern geographical discourse when French geographer Pierre Gourou published Les Pays Tropicaux, in the late 1940s.
Tropicality encompasses at least two contradictory imageries. One is that the tropics represent a Garden of a heaven on Earth; the latter view was discussed in Western literature—more so than the first. Evidence suggests that over time the more primitive view of the tropics in popular literature has been supplanted by more nuanced interpretations that reflect historical changes in values associated with tropical culture and ecology, although some primitive associations are persistent. Western scholars theorized about the reasons that tropical areas were deemed "inferior" to regions in the Northern Hemisphere. A popular explanation focused on the differences in climate—tropical regions have much warmer weather than northern regions; this theme led some scholars, including Gourou, to argue that warmer climates correlate to primitive indigenous populations lacking control over nature, compared to northern popul
A leaf is an organ of a vascular plant and is the principal lateral appendage of the stem. The leaves and stem together form the shoot. Leaves are collectively referred to as foliage, as in "autumn foliage". A leaf is a thin, dorsiventrally flattened organ borne above ground and specialized for photosynthesis. In most leaves, the primary photosynthetic tissue, the palisade mesophyll, is located on the upper side of the blade or lamina of the leaf but in some species, including the mature foliage of Eucalyptus, palisade mesophyll is present on both sides and the leaves are said to be isobilateral. Most leaves have distinct upper surface and lower surface that differ in colour, the number of stomata, the amount and structure of epicuticular wax and other features. Leaves can have many different shapes and textures; the broad, flat leaves with complex venation of flowering plants are known as megaphylls and the species that bear them, the majority, as broad-leaved or megaphyllous plants. In the clubmosses, with different evolutionary origins, the leaves are simple and are known as microphylls.
Some leaves, such as bulb scales, are not above ground. In many aquatic species the leaves are submerged in water. Succulent plants have thick juicy leaves, but some leaves are without major photosynthetic function and may be dead at maturity, as in some cataphylls and spines. Furthermore, several kinds of leaf-like structures found in vascular plants are not homologous with them. Examples include flattened plant stems called phylloclades and cladodes, flattened leaf stems called phyllodes which differ from leaves both in their structure and origin; some structures of non-vascular plants function much like leaves. Examples include the phyllids of liverworts. Leaves are the most important organs of most vascular plants. Green plants are autotrophic, meaning that they do not obtain food from other living things but instead create their own food by photosynthesis, they capture the energy in sunlight and use it to make simple sugars, such as glucose and sucrose, from carbon dioxide and water. The sugars are stored as starch, further processed by chemical synthesis into more complex organic molecules such as proteins or cellulose, the basic structural material in plant cell walls, or metabolised by cellular respiration to provide chemical energy to run cellular processes.
The leaves draw water from the ground in the transpiration stream through a vascular conducting system known as xylem and obtain carbon dioxide from the atmosphere by diffusion through openings called stomata in the outer covering layer of the leaf, while leaves are orientated to maximise their exposure to sunlight. Once sugar has been synthesized, it needs to be transported to areas of active growth such as the plant shoots and roots. Vascular plants transport sucrose in a special tissue called the phloem; the phloem and xylem are parallel to each other but the transport of materials is in opposite directions. Within the leaf these vascular systems branch to form veins which supply as much of the leaf as possible, ensuring that cells carrying out photosynthesis are close to the transportation system. Leaves are broad and thin, thereby maximising the surface area directly exposed to light and enabling the light to penetrate the tissues and reach the chloroplasts, thus promoting photosynthesis.
They are arranged on the plant so as to expose their surfaces to light as efficiently as possible without shading each other, but there are many exceptions and complications. For instance plants adapted to windy conditions may have pendent leaves, such as in many willows and eucalyptss; the flat, or laminar, shape maximises thermal contact with the surrounding air, promoting cooling. Functionally, in addition to carrying out photosynthesis, the leaf is the principal site of transpiration, providing the energy required to draw the transpiration stream up from the roots, guttation. Many gymnosperms have thin needle-like or scale-like leaves that can be advantageous in cold climates with frequent snow and frost; these are interpreted as reduced from megaphyllous leaves of their Devonian ancestors. Some leaf forms are adapted to modulate the amount of light they absorb to avoid or mitigate excessive heat, ultraviolet damage, or desiccation, or to sacrifice light-absorption efficiency in favour of protection from herbivory.
For xerophytes the major constraint drought. Some window plants such as Fenestraria species and some Haworthia species such as Haworthia tesselata and Haworthia truncata are examples of xerophytes. and Bulbine mesembryanthemoides. Leaves function to store chemical energy and water and may become specialised organs serving other functions, such as tendrils of peas and other legumes, the protective spines of cacti and the insect traps in carnivorous plants such as Nepenthes and Sarracenia. Leaves are the fundamental structural units from which cones are constructed in gymnosperms and from which flowers are constructed in flowering plants; the internal organisation of most kinds of leaves has evolved to maximise exposure of the photosynthetic organelles, the chloroplasts, to light and to increase the absorption of carbon dioxide while at the same time controlling water loss. Their surfaces are waterproofed by the plant cuticle and gas exchange between the mesophyll cells and the atmosphere is controlled by minute openings called stomata which open or close to regulate the rate exchange of carbon dioxide and water vapour into
Fuchsia magellanica known as the hummingbird fuchsia or hardy fuchsia, is a species of flowering plant in the family Evening Primrose family, native to the lower Southern Cone of southern South America. This species of Fuchsia occurs in temperate climate southern regions of Argentina and Chile, from latitude 32°50' S. to the Straits of Magellan. In Australia, the species is recorded as naturalised in the states of Western Australia, South Australia, New South Wales and Tasmania; this sub-shrub can grow to 10 feet in height and width in frost-free climates, 4–5 feet where colder. The plant blossoms profusely over a long period with many small and tubular pendent flowers, in brilliant shades of red and purple, softer shades of pink and lavender, some in white. F. magellanica is a variable species across the whole of its natural range and, despite past usage and popular misconceptions, no scientific varieties are recognized by botanist Dr. Paul E. Berry, the leading authority on the genus. Care should be taken not to accord any of the many garden selections and hybrids with taxonomic status by using "var." Additionally, pollen stain tests conducted in the Pacific Northwest region of the United States by members of the Western Fuchsia Species Society have indicated that all of the many garden selections of this species are, in fact, hybrids to a lesser or greater degree.
Fuchsia magellanica, its cultivars and hybrids, are cultivated by plant nurseries and gardeners as an ornamental plant. It is used for planting in temperate and subtropical gardens and within conservatories, for containers on patios and sunny houseplant positions; the plants are quite cold-hardy compared to other species from more tropical climates, being deciduous where frosts are light, only top die back in hard frosts. The profuse drooping flowers are a nectar source attractive to hummingbirds; this species, hybrids using it as parent stock, are susceptible to the fuchsia gall mite, Aculops fuchsiae, a serious disfiguring pest, first accidentally spread from its native Brazil to the West Coast of the United States in 1980. It has more made appearances in France, the Channel Islands and the United Kingdom; the fuchsia gall mite doesn't survive temperatures under 40 °F and there are effective treatments and strategies to combat its appearance. Cultivars of Fuchsia magellanica include: Fuchsia magellanica'Molinae' - lavender with white flowers.
Fuchsia magellanica'Riccartonii' - dark green leaves with a faint bronze sheen. Fuchsia magellanica'Versicolor' - small, grey-green leaves variably margined with cream, pink flush when young. Fuchsia magellanica'Gracilis' - smaller leaves, more arching branch structure. Fuchsia magellanica'Gracilis Variegata' - small, cream-edged leaves, long-narrow crimson and purple flowers Fuchsia magellanica'Aurea' - bronze and gold leaves on deep red stems, vivid magenta and purple flowers. Berry, Paul E. "A Systematic Revision of Fuchsia Sect Quelusia (Onagraceae". Ann. Missouri Bot Gard. 76:532-584. 1989. Media related to Fuchsia magellanica at Wikimedia Commons
Ludwigia is a genus of about 82 species of aquatic plants with a cosmopolitan but tropical distribution. At current, there is much debate among botanists and plant taxonomists as to the classification of many Ludwigia species. Botanists from the US Department of Agriculture are doing genetic analyses on plants from the Western US and South America to better classify members of this genus; the genus was named by Carl Linnaeus after Christian Gottlieb Ludwig, a German botanist, not amused by this honour. A larger number of fossil seeds of †Ludwigia collinsoniae and †Ludwigia corneri have been described from middle Miocene strata of the Fasterholt area near Silkeborg in Central Jutland, Denmark. Listed from the NCBI data base Wagner, W. L. Hoch, P. C. & Raven, P. H.. Revised classification of the Onagraceae. Systematic Botany Monographs, 83. Dressler, S.. "Ludwigia". African plants – a Photo Guide. Frankfurt/Main: Forschungsinstitut Senckenberg
A shrub or bush is a small- to medium-sized woody plant. Unlike herbaceous plants, shrubs have persistent woody, they are distinguished from trees by their multiple stems and shorter height, are under 6 m tall. Plants of many species may grow either depending on their growing conditions. Small, low shrubs less than 2 m tall, such as lavender and most small garden varieties of rose, are termed "subshrubs". An area of cultivated shrubs in a park or a garden is known as a shrubbery; when clipped as topiary, suitable species or varieties of shrubs develop dense foliage and many small leafy branches growing close together. Many shrubs respond well to renewal pruning, in which hard cutting back to a "stool" results in long new stems known as "canes". Other shrubs respond better to selective pruning to reveal their character. Shrubs in common garden practice are considered broad-leaved plants, though some smaller conifers such as mountain pine and common juniper are shrubby in structure. Species that grow into a shrubby habit may be either evergreen.
In botany and ecology, a shrub is more used to describe the particular physical structural or plant life-form of woody plants which are less than 8 metres high and have many stems arising at or near the base. For example, a descriptive system adopted in Australia is based on structural characteristics based on life-form, plus the height and amount of foliage cover of the tallest layer or dominant species. For shrubs 2–8 metres high the following structural forms are categorized: dense foliage cover — closed-shrub mid-dense foliage cover — open-shrub sparse foliage cover — tall shrubland sparse foliage cover — tall open shrublandFor shrubs less than 2 metres high the following structural forms are categorized: dense foliage cover — closed-heath or closed low shrubland— mid-dense foliage cover — open-heath or mid-dense low shrubland— sparse foliage cover — low shrubland sparse foliage cover — low open shrubland Those marked with * can develop into tree form
Hauya is a genus of plants of the family Onagraceae native to montane Central America. They are related to a lineage that gave rise to Circaea. Hauya elegans DC. Hauya heydeana Donn. Sm