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Dendrocnide
''Dendrocnide'' is a genus of approximately 40 species of plants in the nettle family ''Urticaceae''. They have a wide distribution across North East India, Southeast Asia, Australia and the Pacific Islands. In Australia they are commonly known as stinging trees. Description Plants in this genus are evergreen shrubs or small trees, with the exception of the aptly-named giant stinging tree (''D. excelsa'') which may reach in height. Dendrocnide species have a sympodial growth habit and are armed with fine needle-like stinging hairs. They are generally fast-growing and produce soft wood, and are usually found in areas of disturbed forest where they fill the role of a pioneer species. The leaves are simple, alternate, and petiolate, (i.e. having long petioles or leaf-stems), and the leaf blade may be either entire or have some form of dentate toothing (notches or teeth on the edges of the leaf). The leaves are also often large, and may be either leathery or papery. The stipul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dendrocnide Stimulans
''Dendrocnide'' is a genus of approximately 40 species of plants in the nettle family ''Urticaceae''. They have a wide distribution across North East India, Southeast Asia, Australia and the Pacific Islands. In Australia they are commonly known as stinging trees. Description Plants in this genus are evergreen shrubs or small trees, with the exception of the aptly-named giant stinging tree (''D. excelsa'') which may reach in height. Dendrocnide species have a sympodial growth habit and are armed with fine needle-like stinging hairs. They are generally fast-growing and produce soft wood, and are usually found in areas of disturbed forest where they fill the role of a pioneer species. The leaves are simple, alternate, and petiolate, (i.e. having long petioles or leaf-stems), and the leaf blade may be either entire or have some form of dentate toothing (notches or teeth on the edges of the leaf). The leaves are also often large, and may be either leathery or papery. The stipules a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dendrocnide Excelsa
''Dendrocnide excelsa'', commonly known as the giant stinging tree or fibrewood, is a rainforest tree in the family ''Urticaceae'' which is endemic to eastern Australia. It occurs from Tathra, New South Wales to Imbil in southeastern Queensland, and is very common at Dorrigo National Park and other rainforest walks in eastern Australia. The habitat of the giant stinging tree is subtropical, warm temperate or littoral rainforest, particularly in disturbed areas, previously flattened by storms or cyclones. Description ''Dendrocnide excelsa'' is a medium to large-sized tree with a buttressed base, sometimes over 40 metres tall and in excess of 6 metres wide at the base. The DBH is up to . The trunk can be fluted or flanged. The outer bark is grey and smooth, with minor corky markings. The trunk and buttresses are shaped in even curves. The leaves are alternate and toothed, heart-shaped and very large in positions of shade, exceeding 30 cm in length and a similar width. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urticaceae
The Urticaceae are a family, the nettle family, of flowering plants. The family name comes from the genus ''Urtica''. The Urticaceae include a number of well-known and useful plants, including nettles in the genus ''Urtica'', ramie (''Boehmeria nivea''), māmaki ('' Pipturus albidus''), and ajlai ('' Debregeasia saeneb''). The family includes about 2,625 species, grouped into 53 genera according to the database of the Royal Botanic Gardens, Kew and Christenhusz and Byng (2016). The largest genera are '' Pilea'' (500 to 715 species), '' Elatostema'' (300 species), ''Urtica'' (80 species), and '' Cecropia'' (75 species). '' Cecropia'' contains many myrmecophytes. Urticaceae species can be found worldwide, apart from the polar regions. Description Urticaceae species can be shrubs (e.g. '' Pilea''), lianas, herbs (e.g. ''Urtica'', '' Parietaria''), or, rarely, trees ('' Dendrocnide'', '' Cecropia''). Their leaves are usually entire and bear stipules. Urticating (stinging) hai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phyllotaxis
In botany, phyllotaxis () or phyllotaxy is the arrangement of leaf, leaves on a plant stem. Phyllotactic spirals form a distinctive class of patterns in nature. Leaf arrangement The basic leaf#Arrangement on the stem, arrangements of leaves on a stem are opposite and alternate (also known as spiral). Leaves may also be Whorl (botany), whorled if several leaves arise, or appear to arise, from the same level (at the same Node (botany), node) on a stem. With an opposite leaf arrangement, two leaves arise from the stem at the same level (at the same Node (botany), node), on opposite sides of the stem. An opposite leaf pair can be thought of as a whorl of two leaves. With an alternate (spiral) pattern, each leaf arises at a different point (node) on the stem. Distichous phyllotaxis, also called "two-ranked leaf arrangement" is a special case of either opposite or alternate leaf arrangement where the leaves on a stem are arranged in two vertical columns on opposite sides of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pedicel (botany)
In botany, a pedicel is a stem that attaches a single flower to the inflorescence. Such inflorescences are described as ''pedicellate''. Description Pedicel refers to a structure connecting a single flower to its inflorescence. In the absence of a pedicel, the flowers are described as sessile. Pedicel is also applied to the stem of the infructescence. The word "pedicel" is derived from the Latin ''pediculus'', meaning "little foot". The stem or branch from the main stem of the inflorescence that holds a group of pedicels is called a peduncle. A pedicel may be associated with a bract or bracts. In cultivation In Halloween types of pumpkin or squash plants, the shape of the pedicel has received particular attention because plant breeders are trying to optimize the size and shape of the pedicel for the best "lid" for a "jack-o'-lantern". Gallery File:Asclepias amplexicaulis.jpg, Long pedicels of clasping milkweed with a single peduncle File:314 Prunus avium.jpg, Cherr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Achene
An achene (; ), also sometimes called akene and occasionally achenium or achenocarp, is a type of simple dry fruit produced by many species of flowering plants. Achenes are monocarpellate (formed from one carpel) and indehiscent (they do not open at maturity). Achenes contain a single seed that nearly fills the pericarp, but does not adhere to it. In many species, what is called the "seed" is an achene, a fruit containing the seed. The seed-like appearance is owed to the hardening of the fruit wall (pericarp), which encloses the solitary seed so closely as to seem like a seed coat. Examples The fruits of buttercup, buckwheat, caraway, quinoa, amaranth, and cannabis are typical achenes. The achenes of the strawberry are sometimes mistaken for seeds. The strawberry is an accessory fruit with an aggregate of achenes on its outer surface, and what is eaten is accessory tissue. A rose produces an aggregate of achene fruits that are encompassed within an expanded hypanthium (aka f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dioecy
Dioecy (; ; adj. dioecious , ) is a characteristic of a species, meaning that it has distinct individual organisms (unisexual) that produce male or female gametes, either directly (in animals) or indirectly (in seed plants). Dioecious reproduction is biparental reproduction. Dioecy has costs, since only about half the population directly produces offspring. It is one method for excluding self-fertilization and promoting allogamy (outcrossing), and thus tends to reduce the expression of recessive deleterious mutations present in a population. Plants have several other methods of preventing self-fertilization including, for example, dichogamy, herkogamy, and self-incompatibility. Dioecy is a dimorphic sexual system, alongside gynodioecy and androdioecy. In zoology In zoology, dioecious species may be opposed to hermaphroditic species, meaning that an individual is either male or female, in which case the synonym gonochory is more often used. Most animal species are dioecious (gon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Merosity
Merosity (from the greek "méros," which means "having parts") refers to the number of component parts in a distinct whorl of a plant structure. The term is most commonly used in the context of a flower where it refers to the number of sepals in a whorl of the calyx, the number of petals in a whorl of the corolla, the number of stamens in a whorl of the androecium, or the number of carpels in a whorl of the gynoecium. The term may also be used to refer to the number of leaves in a leaf whorl. The adjective ''n''-merous refers to a whorl of ''n'' parts, where ''n'' is any integer greater than one. In nature, five or three parts per whorl have the highest frequency of occurrence, but four or two parts per whorl are not uncommon. Be aware that two consecutive whorls of dimerous petals are often mistaken for tetramerous petals. If all of the whorls in a given floral arrangement have the same merosity, the flower is said to be isomerous, otherwise the flower is anisomerous. For exampl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Panicle
A panicle is a much-branched inflorescence. (softcover ). Some authors distinguish it from a compound spike inflorescence, by requiring that the flowers (and fruit) be pedicellate (having a single stem per flower). The branches of a panicle are often racemes. A panicle may have determinate or indeterminate growth. This type of inflorescence is largely characteristic of grasses such as oat and crabgrass, as well as other plants such as pistachio and mamoncillo. Botanists use the term paniculate in two ways: "having a true panicle inflorescence" as well as "having an inflorescence with the form but not necessarily the structure of a panicle". Corymb A corymb may have a paniculate branching structure, with the lower flowers having longer pedicels than the upper, thus giving a flattish top superficially resembling an umbel. Many species in the subfamily Amygdaloideae, such as hawthorns and rowans, produce their flowers in corymbs. up'' Sorbus glabrescens'' corymb with fruit See ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Raceme
A raceme ( or ) or racemoid is an unbranched, indeterminate type of inflorescence bearing flowers having short floral stalks along the shoots that bear the flowers. The oldest flowers grow close to the base and new flowers are produced as the shoot grows in height, with no predetermined growth limit. Examples of racemes occur on mustard (genus ''Brassica'') and radish (genus ''Raphanus'') plants. Definition A ''raceme'' or ''racemoid'' is an unbranched, indeterminate type of inflorescence bearing pedicellate flowers (flowers having short floral stalks called ''pedicels'') along its axis. In botany, an ''axis'' means a shoot, in this case one bearing the flowers. In indeterminate inflorescence-like racemes, the oldest flowers grow close to the base and new flowers are produced as the shoot grows in height, with no predetermined growth limit. A plant that flowers on a showy raceme may have this reflected in its scientific name, e.g. the species ''Cimicifuga racemosa''. A compou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peduncle (botany)
In botany, a peduncle is a stalk supporting an inflorescence or a solitary flower, or, after fecundation, an infructescence or a solitary fruit. The peduncle sometimes has bracts (a type of cataphylls) at nodes. The main axis of an inflorescence above the peduncle is the rachis. There are no flowers on the peduncle but there are flowers on the rachis. When a peduncle arises from the ground level, either from a compressed aerial stem or from a subterranean stem (rhizome, tuber, bulb, corm), with few or no bracts except the part near the rachis or receptacle, it is referred to as a scape. The acorns of the pedunculate oak are borne on a long peduncle, hence the name of the tree. See also *Pedicel (botany) *Scape (botany) In botany, a scape is a peduncle arising from a subterranean or very compressed stem, with the lower internodes very long and hence few or no bracts except the part near the rachis or receptacle. Typically it takes the form of a long, leafles ... Re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glossary Of Botanical Terms
This glossary of botanical terms is a list of definitions of terms and concepts relevant to botany and plants in general. Terms of plant morphology are included here as well as at the more specific Glossary of plant morphology and Glossary of leaf morphology. For other related terms, see Glossary of phytopathology, Glossary of lichen terms, and List of Latin and Greek words commonly used in systematic names. A B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
