Tree - Wikipedia, the free encyclopedia
"Reproduction Main article: Plant reproduction Form, leaves and reproductive structures of queen sago Cycas circinalis Tree forms are found in a wide range of plants and their reproductive strategies are substantially the same as shrub or herbaceous plant forms. Many trees are wind pollinated which may be an evolutionary adaptation to take advantage of increased wind speeds high above the ground, particularly in the case of those that produce pollen before the leaves emerge.[64] A vast quantity of pollen is produced because of the low likelihood of any particular grain landing on an appropriate female flower. Wind-pollinated flowers of broad-leaved trees are characterised by a lack of showy parts, no scent and a copious production of pollen, often with separate male and female flowers, or separate male and female trees. The male flowers may be high up in the tree, often in the form of dangling catkins. The female flowers may be lower down the tree. The pollen of pine trees contains air sacs which give it buoyancy and it has been known to travel as far as 800 kilometres (500 mi).[65] Tree pollen can cause allergies. A prime example would be hay fever, which can be caused by pollen."
- - By Seth Irving
Reproduction
Main article: Plant reproduction
Form, leaves and reproductive structures of queen sago Cycas circinalis
Tree forms are found in a wide range of plants and their reproductive strategies are substantially the same as shrub or herbaceous plant forms.
Many trees are wind pollinated which may be an evolutionary adaptation to take advantage of increased wind speeds high above the ground, particularly in the case of those that produce pollen before the leaves emerge.[64] A vast quantity of pollen is produced because of the low likelihood of any particular grain landing on an appropriate female flower. Wind-pollinated flowers of broad-leaved trees are characterised by a lack of showy parts, no scent and a copious production of pollen, often with separate male and female flowers, or separate male and female trees. The male flowers may be high up in the tree, often in the form of dangling catkins. The female flowers may be lower down the tree. The pollen of pine trees contains air sacs which give it buoyancy and it has been known to travel as far as 800 kilometres (500 mi).[65] Tree pollen can cause allergies. A prime example would be hay fever, which can be caused by pollen.
- The earliest tree-like organisms were tree ferns, horsetails and lycophytes, which grew in forests in the Carboniferous period.
Trees are an important part of the terrestrial ecosystem,[86] providing essential habitat for a community of organisms. Epiphytic plants such as ferns, some mosses, liverworts, orchids and some species of parasitic plants (e.g., mistletoe) hang from branches; these along with arboreal lichens, algae, and fungi provide micro-habitats for themselves and for other organisms, including animals. Leaves, flowers and fruits are seasonally available. On the ground underneath trees there is shade, and often there is undergrowth, leaf litter, fallen branches and/or decaying wood that provide other habitat. Trees stabilise the soil, prevent rapid run-off of rain water, help prevent desertification, have a role in climate control and help in the maintenance of biodiversity and ecosystem balance.[87]
Many species of tree support their own specialised invertebrates.
- Trees have their roots in the ground and their trunk and branches extended towards the sky. This concept is found in many of the world's religions as a tree which links the underworld and the earth and holds up the heavens. In Norse mythology, Yggdrasil is a central cosmic tree whose roots and branches extend to various worlds. Various creatures live on it.[133] In India, Kalpavriksha is a wish-fulfilling tree that was one of nine jewels that emerged from the primitive ocean. Icons are placed beneath it to be worshipped, tree nymphs inhabit the branches and it grants favours to the devout who tie threads round the trunk.[134] Democracy started in North America when the Great Peacemaker formed the Iroquois Confederacy, inspiring the warriors of the original five American nations to bury their weapons under the Tree of Peace, an eastern white pine (Pinus strobus).[135] In the creation story in the Bible, the tree of life and the knowledge of good and evil was planted by God in the Garden of Eden.
- The gymnosperms include conifers, cycads, gnetales and ginkgos and these may have appeared as a result of a whole genome duplication event which took place about 319 million years ago.
Cypress - Wikipedia, the free encyclopedia
- Cypress is the name applied to many plants in the cypress family Cupressaceae, which is a conifer of northern temperate regions. Most cypress species are trees, while a few are shrubs. Most plants bearing the common name cypress are in the genera Cupressus and Chamaecyparis, but several other genera in the family also carry the name. The cypress tree is also a symbol of Artemis, the Greek goddess of the hunt, young girls, and the moon, very unlike her twin brother, Apollo, the Greek god of the sun, music, healing, and prophecies.
- African Cypress (Widdringtonia species)
- Bald, Pond, and Montezuma Cypresses (Taxodium species, native to North America)
- Chinese Swamp Cypress (Glyptostrobus pensilis)
- Cordilleran Cypress (Austrocedrus chilensis)
- Cypress (Callitropsis species)
- Cypress (Cupressus species)
- Cypress-pines (Actinostrobus species)
- Cypress-pines (Callitris species)
- False Cypress (Chamaecyparis species)
- Fujian Cypress (Fokienia hodginsii)
- Guaitecas Cypress (Pilgerodendron uviferum)
- Patagonian Cypress (Fitzroya cupressoides)
- Siberian Cypress (Microbiota decussata)
The Cupressaceae family also contains 13-16 other genera (not listed above) that do not bear cypress in their common names.
Element Collab - Current Concepts
- - By Seth Irving
- - By Seth Irving
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