A tree is a perennial A perennial plant or perennial is a plant that lives for more than two years. When used by gardeners or horticulturalists, applies specifically to winter hardy perennial herbaceous plants. Scientifically, woody plants like shrubs and trees are also perennial in their habit woody plant A woody plant is a plant that uses wood as its structural tissue. They are typically perennial plants that have their stems and larger roots reinforced with wood produced adjacent to the vascular tissues: typically the main stem and larger branches and roots are covered by a layer of thickened bark. Woody plants are usually either trees, shrubs,. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or trunk In botany, trunk refers to the main structural member of a tree that supports the branches and is supported by and directly attached to the roots. The trunk is covered by the bark, which is an important diagnostic feature in tree identification, and which often differs markedly from the bottom of the trunk to the top, depending on the species. The with clear apical dominance.[1] A minimum height specification at maturity is cited by some authors, varying from 3 m The metre , symbol m, is the base unit of length in the International System of Units (SI). Originally intended to be one ten-millionth of the distance from the Earth's equator to the North Pole, its definition has been periodically refined to reflect growing knowledge of metrology. Since 1983, it is defined as the distance travelled by light in[2] to 6 m;[3] some authors set a minimum of 10 cm trunk diameter (30 cm girth).[4] Woody plants that do not meet these definitions by having multiple stems and/or small size are called shrubs A shrub or bush is distinguished from a tree by its multiple stems and lower height, usually less than 5–6 m tall. A large number of plants can be either shrubs or trees, depending on the growing conditions they experience. Small, low shrubs such as lavender, periwinkle and thyme are often termed subshrubs. Compared with most other plants, trees are long-lived, some reaching several thousand years old and growing to up to 115 m (379 ft) high.[5]
Trees are an important component of the natural landscape Natural landscapes are landscapes beyond cultural influence. "A natural landscape is one that is unaffected by human activity", SES501 Landscape Ecology and GIS, Keith Ferdinands, Charles Darwin University, July 2004, because of their prevention of erosion Erosion is the process of weathering and transport of solids in the natural environment or their source and deposits them elsewhere. It usually occurs due to transport by wind, water, or ice; by down-slope creep of soil and other material under the force of gravity; or by living organisms, such as burrowing animals, in the case of bioerosion and the provision of a weather-sheltered ecosystem An ecosystem consists of all the organisms living in a particular area, as well as all the nonliving, physical components of the environment with which the organisms interact, such as air, soil, water, and sunlight. It is all the organisms in a given area, along with the nonliving factors with which they interact; a biological community and its in and under their foliage In botany, a leaf is an above-ground plant organ specialized for photosynthesis. For this purpose, a leaf is typically flat and thin. As an evolutionary trait, the flatness of leaves works to expose the chloroplasts to more light and to increase the absorption of carbon dioxide at the expense of water loss. In the Devonian period, when carbon. They also play an important role in producing oxygen Oxygen (pronounced /ˈɒksɨdʒɨn/, OK-si-jin, from the Greek roots ὀξύς (acid, literally "sharp", from the taste of acids) and -γενής (-genēs) (producer, literally begetter), is the element with atomic number 8 and represented by the symbol O. It is a member of the chalcogen group on the periodic table, and is a highly and reducing carbon dioxide Carbon dioxide is a chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom. It is a gas at standard temperature and pressure and exists in Earth's atmosphere in this state. CO2 is a trace gas comprising 0.039% of the atmosphere in the atmosphere, as well as moderating ground temperatures. They are also elements in landscaping Landscape architecture is the design of outdoor and public spaces to achieve environmental, socio-behavioral, and/or aesthetic outcomes. It involves the systematic investigation of existing social, ecological, and geological conditions and processes in the landscape, and the design of interventions that will produce the desired outcome. The scope and agriculture Agriculture is the production of food and goods through farming. Agriculture was the key development that led to the rise of human civilization, with the husbandry of domesticated animals and plants creating food surpluses that enabled the development of more densely populated and stratified societies. The study of agriculture is known as, both for their aesthetic Aesthetics is a branch of philosophy dealing with the nature of beauty, art, and taste, and with the creation and appreciation of beauty. It is more scientifically defined as the study of sensory or sensori-emotional values, sometimes called judgments of sentiment and taste. More broadly, scholars in the field define aesthetics as "critical appeal and their orchard An orchard is an intentional planting of trees or shrubs maintained for food production. Orchards comprise fruit or nut-producing trees grown for commercial production. Orchards are also sometimes a feature of large gardens, where they serve an aesthetic as well as a productive purpose. A fruit garden is generally synonymous with an orchard, crops (such as apples The apple is the pomaceous fruit of the apple tree, species Malus domestica in the rose family and is a perennial. It is one of the most widely cultivated tree fruits, and the most widely known of the many members of genus Malus that are used by humans). Wood Wood is a hard, fibrous tissue found in many plants. It has been used for centuries for both fuel and as a construction material for several types of living areas such as houses. It is an organic material, a natural composite of cellulose fibers embedded in a matrix of lignin which resists compression. In the strict sense wood is produced as from trees is a building material Building material is any material which is used for a construction purpose. Many naturally occurring substances, such as clay, sand, wood and rocks, even twigs and leaves have been used to construct buildings. Apart from naturally occurring materials, many man-made products are in use, some more and some less synthetic. The manufacture of building, as well as a primary energy source in many developing countries. Trees also play a role in many of the world's mythologies The term mythology can refer to either the study of myths, or to a body of myths. For example, comparative mythology is the study of connections between myths from different cultures, whereas Greek mythology is the body of myths from ancient Greece. The term "myth" is often used colloquially to refer to a false story, but academic use of (see trees in mythology Tree worship refers to the tendency of many societies throughout history to worship or otherwise mythologize trees. Trees have played an important role in many of the world's mythologies and religions, and have been given deep and sacred meanings throughout the ages. Human beings, observing the growth and death of trees, the elasticity of their).[6]
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Classification
A Sweet Chestnut Castanea sativa is a species of the flowering plant family Fagaceae, the tree and its edible seeds are referred to by several common names such Sweet Chestnut or Marron. Originally native to southeastern Europe and Asia Minor, it is now widely dispersed throughout Europe. The trees are hardy, long lived and well known, especially for its chestnuts tree in Ticino Canton Ticino or Ticino is the southernmost canton of Switzerland. Named after the Ticino river, it is the only canton in which Italian is the sole official language. Ticino borders the Canton of Uri to the north, Valais to the west (through the Novena Pass), Graubünden to the northeast, Italy's regions of Piedmont and Lombardy to the south and, Switzerland Switzerland , officially the Swiss Confederation (Confœderatio Helvetica in Latin, hence its ISO country codes CH and CHE), is a federal republic consisting of 26 cantons, with Bern as the seat of the federal authorities. The country is situated in Western Europe[note 4] where it is bordered by Germany to the north, France to the west, Italy toA tree is a plant form that occurs in many different orders The Latin suffix -formes meaning "having the form of" is used for the scientific name of orders of birds and fishes, but not for those of mammals and invertebrates and families What does and does not belong to each family is determined by a taxonomist. Similarly for the question if a particular family should be recognized at all. Often there is no exact agreement, with different taxonomists each taking a different position. There are no hard rules that a taxonomist needs to follow in describing or recognizing a family of plants. Trees show a variety of growth forms Plant life-form schemes constitute a way of classifying plants alternatively to the ordinary species-genus-family scientific classification. In colloquial speech, plants may be classified as trees, shrubs, herbs , etc. The scientific use of life-form schemes emphasizes plant function in the ecosystem and that the same function or "adaptedness&, leaf type and shape, bark characteristics and reproductive organs A sex organ, or primary sexual characteristic, as narrowly defined, is any of the anatomical parts of the body which are involved in sexual reproduction and constitute the reproductive system in a complex organism; flowers are the reproductive organs of flowering plants, cones are the reproductive organs of coniferous plants , whereas mosses,.
The tree form has evolved separately in unrelated classes of plants, in response to similar environmental challenges, making it a classic example of parallel evolution Parallel evolution is the development of a similar trait in different not closely related species , but descending from the same ancestor. With an estimate of 100,000 tree species In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are often used, such as similarity of DNA, morphology or, the number of tree species worldwide might total 25 percent of all living plant Plants are living organisms belonging to the kingdom Plantae. They include familiar organisms such as trees, herbs, bushes, grasses, vines, ferns, mosses, and green algae. The scientific study of plants, known as botany, has identified about 350,000 extant species of plants, defined as seed plants, bryophytes, ferns and fern allies. As of 2004, species.[7] The majority of tree species grow in tropical The tropics is a region of the Earth by the Equator. It is limited in latitude by the Tropic of Cancer in the northern hemisphere at approximately 23° 26′ 16″ N and the Tropic of Capricorn in the southern hemisphere at 23° 26′ 16″ ( or 23.438° ) S. The tropics are also referred to as the tropical zone and the torrid zone (see regions of the world and many of these areas have not been surveyed yet by botanists Botany, plant science, phytology, or plant biology is a branch of biology that involves the scientific study of plant life. Botany covers a wide range of scientific disciplines concerned with the study of plants, algae and fungi, including structure, growth, reproduction, metabolism, development, diseases, chemical properties, and evolutionary, making species diversity and ranges poorly understood.[8]
Tropical tree in Campeche Campeche is a state in the southeast of Mexico. It is bordered by the Mexican states of Yucatán to the north east, Quintana Roo to the east, and Tabasco to the south west. To the south it is bordered by the Petén department of Guatemala and to the west by the Gulf of Mexico, Mexico In Pre-Columbian Mesoamerica many cultures matured into advanced civilizations such as the Olmec, the Toltec, the Teotihuacan, the Zapotec, the Maya and the Aztec before the first contact with Europeans. In 1521, Spain conquered and colonized the territory, which was administered as the viceroyalty of New Spain which would eventually become Mexico.The earliest trees were tree ferns The order Cyatheales is a taxonomic division of the fern subclass, Cyatheatae, which includes the tree ferns. No clear morphological features characterize all of the Cyatheales, but DNA sequence data indicates that the order is monophyletic. Some species in the Cyatheales have tree-like growth forms, but others have creeping rhizomes . Some, horsetails Equisetum is the only living genus in the Equisetaceae, a family of vascular plants that reproduce by spores rather than seeds. They are commonly known as horsetails and lycophytes The Division Lycopodiophyta is a tracheophyte subdivision of the Kingdom Plantae. It is the oldest extant (living) vascular plant division at around 410 million years old,:99 and includes some of the most "primitive" extant species. These species reproduce by shedding spores and have macroscopic alternation of generations, although some, which grew in forests A forest is an area with a high density of trees. There are many definitions of a forest, based on the various criteria. These plant communities cover approximately 9.4% of the Earth's surface (or 30% of total land area), though they once covered much more (about 50% of total land area), in many different regions and function as habitats for in the Carboniferous The Carboniferous is a geologic period and system that extends from the end of the Devonian Period, about 359.2 ± 2.5 Ma , to the beginning of the Permian Period, about 299.0 ± 0.8 Ma (ICS, 2004, period; tree ferns still survive, but the only surviving horsetails and lycophytes are not of tree form. Later, in the Triassic The Triassic is a geologic period that extended from about 250 to 200 Mya . As the first period of the Mesozoic Era, the Triassic follows the Permian and is followed by the Jurassic. Both the start and end of the Triassic are marked by major extinction events. The extinction event that closed the Triassic Period has recently been more accurately period, conifers The conifers, division Pinophyta, also known as division Coniferophyta or Coniferae, are one of 13 or 14 division level taxa within the Kingdom Plantae. Pinophytes are gymnosperms. They are cone-bearing seed plants with vascular tissue; all extant conifers are woody plants, the great majority being trees with just a few being shrubs. Typical, ginkgos Ginkgo is a genus of highly unusual non-flowering plants with one extant species, G. biloba, which is regarded as a living fossil, cycads Cycads are seed plants characterized by a large crown of compound leaves and a stout trunk. They are evergreen, dioecious plants having large pinnately compound leaves. They are frequently confused with and mistaken for palms or ferns, but are only distantly related to both, and instead belong to the division Cycadophyta and other gymnosperms Once an authoritative and major classification level in the plant kingdom, the gymnosperms form today a rather heterogeneous group of seed-bearing plants that includes conifers, cycads, Ginkgo and Gnetales. The term "gymnosperm" comes from the Greek word gymnospermos , meaning "naked seeds", after the unenclosed condition of appeared, and subsequently flowering plants The flowering plants , also known as Angiospermae or Magnoliophyta, are the most diverse group of land plants. Together with gymnosperms, they are the only extant groups of seed-producing plants, but they can be distinguished from the gymnosperms by a series of synapomorphies (derived characteristics). These characteristics include flowers, in the Cretaceous The Cretaceous , Latin for "chalky", usually abbreviated K for its German translation Kreide (chalk), is a geologic period and system from circa 145.5 ± 4 to 65.5 ± 0.3 million years (Ma) ago. In the geologic timescale, the Cretaceous follows on the Jurassic Period and is followed by the Paleogene Period of the Cenozoic Era. It is the period. Most species of trees today are flowering plants (Angiosperms The flowering plants , also known as Angiospermae or Magnoliophyta, are the most diverse group of land plants. Together with gymnosperms, they are the only extant groups of seed-producing plants, but they can be distinguished from the gymnosperms by a series of synapomorphies (derived characteristics). These characteristics include flowers,) and conifers. For the listing of examples of well-known trees and how they are classified, see List of tree genera The major tree genera are listed below by taxonomic family.
A small group of trees growing together is called a grove A grove is a small group of trees, such as a sequoia grove, or a small orchard planted for the cultivation of fruits or nuts. Other words for groups of trees include woodland, copse, woodlot, thicket or spinney or copse, and a landscape covered by a dense growth of trees is called a forest A forest is an area with a high density of trees. There are many definitions of a forest, based on the various criteria. These plant communities cover approximately 9.4% of the Earth's surface (or 30% of total land area), though they once covered much more (about 50% of total land area), in many different regions and function as habitats for. Several biotopes are defined largely by the trees that inhabit them; examples are rainforest and taiga (see ecozones). A landscape of trees scattered or spaced across grassland (usually grazed or burned over periodically) is called a savanna. A forest of great age is called old growth forest or ancient woodland (in the UK). A young tree is called a sapling.
Morphology
Beech leaves. Tree roots anchor the structure and provide water and nutrients. The ground has eroded away around the roots of this young pine tree.The parts of a tree are the roots, trunk(s), branches, twigs and leaves. Tree stems consist mainly of support and transport tissues (xylem and phloem). Wood consists of xylem cells, and bark is made of phloem and other tissues external to the vascular cambium. Trees may be grouped into exogenous and endogenous trees according to the way in which their stem diameter increases. Exogenous trees, which comprise the great majority of trees (all conifers, and almost all broadleaf trees), grow by the addition of new wood outwards, immediately under the bark. Endogenous trees, mainly in the monocotyledons (e.g., palms and dragon trees), but also cacti, grow by addition of new material inwards.[clarification needed]
As an exogenous tree grows, it creates growth rings as new wood is laid down concentrically over the old wood. In species growing in areas with seasonal climate changes, wood growth produced at different times of the year may be visible as alternating light and dark, or soft and hard, rings of wood.[3] In temperate climates, and tropical climates with a single wet-dry season alternation, the growth rings are annual, each pair of light and dark rings being one year of growth; these are known as annual rings. In areas with two wet and dry seasons each year, there may be two pairs of light and dark rings each year; and in some (mainly semi-desert regions with irregular rainfall), there may be a new growth ring with each rainfall.[9] In tropical rainforest regions, with constant year-round climate, growth is continuous and the growth rings are not visible nor is there a change in the wood texture. In species with annual rings, these rings can be counted to determine the age of the tree, and used to date cores or even wood taken from trees in the past, a practice known as the science of dendrochronology. Very few tropical trees can be accurately dated in this manner. Age determination is also impossible in endogenous trees.
The roots of a tree are generally embedded in earth, providing anchorage for the above-ground biomass and absorbing water and nutrients from the soil. However, while ground nutrients are essential to a tree's growth the majority of its biomass comes from carbon dioxide absorbed from the atmosphere (see photosynthesis). Above ground, the trunk gives height to the leaf-bearing branches, aiding in competition with other plant species for sunlight. In many trees, the arrangement of the branches optimizes exposure of the leaves to sunlight.
Not all trees have all the plant organs or parts mentioned above. For example, most palm trees are not branched, the saguaro cactus of North America has no functional leaves, tree ferns do not produce bark, etc. Based on their general shape and size, all of these are nonetheless generally regarded as trees. A plant form that is similar to a tree, but generally having smaller, multiple trunks and/or branches that arise near the ground, is called a shrub. However, no precise differentiation between shrubs and trees is possible. Given their small size, bonsai plants would not technically be 'trees', but one should not confuse reference to the form of a species with the size or shape of individual specimens. A spruce seedling does not fit the definition of a tree, but all spruces are trees.
Record breaking trees
The world's champion trees can be rated on height, trunk diameter or girth, total size, and age.
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Sun, 15 Aug 2010 00:41:26 GMT+00:00
planted in memory of Parker teens killed in crash kwgn.com Two Parker teenagers who were killed in a recent car crash were remembered Saturday with trees planted in their honor at their high school. ...
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Sat, 21 Aug 2010 04:25:57 GM
You see, this is a . Tree. Planting Robot, designed for reforestation projects. The . Tree. Planting Robot is good for carrying 320 seedlings, with each one in a biodegradable plastic protective barrier that protects it from plant-eating ...
