A pebble is a clast of rock with a particle size of 2 to 64 millimetres based on the Krumbein phi scale of sedimentology. Pebbles are considered larger than granules and smaller than cobbles. A rock made predominantly of pebbles is termed a conglomerate. Pebble tools are among the earliest known man-made artifacts, dating from the Palaeolithic period of human history. A beach composed chiefly of surface pebbles is termed a shingle beach; this type of beach has armoring characteristics with respect to wave erosion, as well as ecological niches that provide habitat for animals and plants. Inshore banks of shingle exist in some locations, such as the entrance to the River Ore, where the moving banks of shingle give notable navigational challenges. Pebbles come in various colors and textures and can have streaks, known as veins, of quartz or other minerals. Pebbles are smooth but, dependent on how they come in contact with the sea, they can have marks of contact with other rocks or other pebbles. Pebbles left above the high water mark may have growths of organisms such as lichen on them, signifying the lack of contact with seawater.
Pebbles are found in two locations – on the beaches of various oceans and seas, inland where ancient seas used to cover the land. When the seas retreated, the rocks became landlocked, they can be found in lakes and ponds. Pebbles can form in rivers, travel into estuaries where the smoothing continues in the sea. Beach pebbles and river pebbles are distinct in their geological appearance. Beach pebbles form over time as the ocean water washes over loose rock particles; the result is a rounded appearance. The typical size range is from 2 mm to 50 mm; the colors range from translucent white to black, include shades of yellow, brown and green. Some of the more plentiful pebble beaches are found along the coast of the Pacific Ocean, beginning in the United States and extending down to the tip of South America in Argentina. Other pebble beaches are found in northern Europe, along the coast of the U. K. and Ireland, on the shores of Australia, around the islands of Indonesia and Japan. Inland pebbles are found along the shores of large rivers and lakes.
These pebbles form as the flowing water washes over rock particles on the bottom and along the shores of the river. The smoothness and color of river pebbles depends on several factors, such as the composition of the soil of the river banks, the chemical characteristics of the water, the speed of the current; because river current is gentler than the ocean waves, river pebbles are not as smooth as beach pebbles. The most common colors of river rock are black, green and white. Beach pebbles and river pebbles are used for a variety of both outdoors and indoors, they can be sorted by colour and size, they can be polished to improve the texture and colour. Outdoors, beach pebbles are used for landscaping, construction and as decorative elements. Beach pebbles are used to cover walkways and driveways, around pools, in and around plant containers, on patios and decks. Beach and river pebbles are used to create water-smart gardens in areas where water is scarce. Small pebbles are used to create living spaces and gardens on the rooftops of buildings.
Indoors, pebbles can be used as paperweights. Large pebbles are used to create "pet rocks" for children. On Mars, slabs of pebbly conglomerate rock have been found and have been interpreted by scientists as having formed in an ancient streambed; the gravels, which were discovered by NASA's Mars rover Curiosity, range from the size of sand particles to the size of golf balls. Analysis has shown that the pebbles were deposited by a stream that flowed at walking pace and was ankle- to hip-deep. Gravel Japanese Garden of Peace Media related to Pebbles at Wikimedia Commons
A moat is a deep, broad ditch, either dry or filled with water, dug and surrounds a castle, building or town to provide it with a preliminary line of defence. In some places moats evolved into more extensive water defences, including natural or artificial lakes and sluices. In older fortifications, such as hillforts, they are referred to as ditches, although the function is similar. In periods, moats or water defences may be ornamental, they could act as a sewer. Some of the earliest evidence of moats has been uncovered around ancient Egyptian castles. One example is at a castle excavated in Nubia. Other evidence of ancient moats is found in the ruins of Babylon, in reliefs from ancient Egypt and other cultures in the region. Evidence of early moats around settlements has been discovered in many archaeological sites throughout Southeast Asia, including Noen U-Loke, Ban Non Khrua Chut, Ban Makham Thae and Ban Non Wat; the use of the moats could have been either for agriculture purposes. Moats were excavated around castles and other fortifications as part of the defensive system as an obstacle outside the walls.
In suitable locations they might be filled with water. A moat made access to the walls difficult for siege weapons, such as siege towers and battering rams, which needed to be brought up against a wall to be effective. A water-filled moat made the practice of mining, digging tunnels under the castles in order to effect a collapse of the defences difficult as well. Segmented moats have one section filled with water. Dry moats cut across the narrow part of a spur or peninsula are called neck ditches. Moats separating different elements of a castle, such as the inner and outer wards are cross ditches; the word adapted in Middle English from the Old French motte "mound, hillock" and was first applied to the central mound on which a castle was erected, came to be applied to the excavated ring, a "dry moat". The shared derivation implies that the two features were related and constructed at the same time; the term moat is applied to natural formations reminiscent of the artificial structure, to similar modern architectural features.
With the introduction of siege artillery, a new style of fortification emerged in the 16th century using low walls and projecting strong points called bastions, known as the trace italienne. The walls were further protected from infantry attack by wet or dry moats, sometimes in elaborate systems; when this style of fortification was superseded by lines of polygonal forts in the mid-19th century, moats continued to be used for close protection. The Walls of Benin were a combination of ramparts and moats, called Iya, used as a defense of the capital Benin City in present-day Edo State of Nigeria, it was considered the largest man-made structure lengthwise, second only to the Great Wall of China and the largest earthwork in the world. With more recent work by Patrick Darling, it has been established as the largest man-made structure in the world, larger than Sungbo's Eredo in Nigeria, it enclosed 6,500 km2 of community lands. Its length was over 16,000 km of earth boundaries, it was estimated that earliest construction continued into the mid-15th century.
The walls are built of a dike structure. The Benin Walls were ravaged by the British in 1897. Scattered pieces of the walls remain in Edo, with material being used by the locals for building purposes; the walls continue to be torn down for real estate developments. The Walls of Benin City were the world's largest man-made structure. Fred Pearce wrote in New Scientist: "They extend for some 16,000 kilometres in all, in a mosaic of more than 500 interconnected settlement boundaries, they were all dug by the Edo people. In all, they are four times longer than the Great Wall of China, consumed a hundred times more material than the Great Pyramid of Cheops, they took an estimated 150 million hours of digging to construct, are the largest single archaeological phenomenon on the planet." Japanese castles have elaborate moats, sometimes with many moats laid out in concentric circles around the castle and a host of different patterns engineered around the landscape. Japanese castles will have up to three of these concentric moats.
The outer moat of Japanese castles protects other support buildings in addition to the castle. As many Japanese castles have been a central part of their respective city, the moats have provided a vital waterway to the city. In modern times, the moat system of the Tokyo Imperial Palace comprises a active body of water, hosting everything from rental boats and fishing ponds to restaurants. Most modern Japanese castles have moats filled with water, but castles in the feudal period more had'dry moats' karabori, a trench. A tatebori is a dry moat. A unejo tatebori is a series of parallel trenches running up the sides of the excavated mountain, the earthen wall, called doi, was an outer wall made of earth dug out from a moat. Today, it is common for mountain Japanese castles to have dry moats. A mizubori is a moat filled with water. Moats were used in the Forbidden City and Xi'an in China; the only moat fort b
A bulldozer or dozer is a crawler equipped with a substantial metal plate used to push large quantities of soil, rubble, or other such material during construction or conversion work and equipped at the rear with a claw-like device to loosen densely compacted materials. Bulldozers can be found on a wide range of sites and quarries, military bases, heavy industry factories, engineering projects and farms; the term "bulldozer" refers only to a tractor fitted with a dozer blade. Bulldozers are large and powerful tracked heavy equipment; the tracks give them excellent ground holding capability and mobility through rough terrain. Wide tracks help distribute the bulldozer's weight over a large area, thus preventing it from sinking in sandy or muddy ground. Extra wide tracks are known as LGP tracks. Bulldozers have transmission systems designed to take advantage of the track system and provide excellent tractive force; because of these attributes, bulldozers are used in road building, mining, land clearing, infrastructure development, any other projects requiring mobile and stable earth-moving equipment.
Another type of bulldozer is the wheeled bulldozer, which has four wheels driven by a 4-wheel-drive system and has a hydraulic, articulated steering system. The blade is mounted forward of the articulation joint, is hydraulically actuated; the bulldozer's primary tools are the ripper. The word "bulldozer" is sometimes used inaccurately for other similar construction vehicles such as a large front loader; the bulldozer blade is a heavy metal plate on the front of the tractor, used to push objects, shove sand, soil and sometimes snow. Dozer blades come in three varieties: A straight blade, short and has no lateral curve and no side wings and can be used for fine grading. A universal blade, tall and curved, has large side wings to carry more material. An "S-U" combination blade, shorter, has less curvature, smaller side wings; this blade is used for pushing piles of large rocks, such as at a quarry. Blades can be fitted straight across the frame, or at an angle, sometimes using additional'tilt cylinders' to vary the angle while moving.
The bottom edge of the blade can be sharpened. Sometimes a bulldozer is used to push another piece of earth moving equipment known as a "scraper"; the towed Fresno Scraper, invented in 1883 by James Porteous, was the first design to enable this to be done economically, removing the soil from the cut and depositing it elsewhere on shallow ground. Many dozer blades have a reinforced center section with this purpose in mind, are called "bull blades". In military use, dozer blades are fixed on combat engineering vehicles and can optionally be fitted on other vehicles, such as artillery tractors such as the Type 73 or M8 Tractor. Dozer blades can be mounted on main battle tanks, where it can be used to clear antitank obstacles and dig improvised shelters. Combat applications for dozer blades include clearing battlefield obstacles and preparing fire positions; the ripper is the long claw-like device on the back of the bulldozer. Rippers can come in groups of two or more. A single shank is preferred for heavy ripping.
The ripper shank is fitted with a replaceable tungsten steel alloy tip, referred to as a'boot'. Ripping rock breaks the ground surface rock or pavement into small rubble easy to handle and transport, which can be removed so grading can take place. With agricultural ripping, a farmer breaks up rocky or hard earth, otherwise unploughable, in order to farm it. For example, much of the best land in the California wine country consists of old lava flows; the grower shatters the lava with heavy bulldozers so surface trees can be planted. Some bulldozers are equipped with a less common rear attachment referred to as a stumpbuster, a single spike that protrudes horizontally and can be raised to get it out of the way. A stumpbuster is used to split a tree stump. A bulldozer with a stumpbuster is used for landclearing operations, is equipped with a brush-rake blade. Bulldozers have been further modified over time to evolve into new machines which can work in ways that the original bulldozer cannot. One example is that loader tractors were created by removing the blade and substituting a large volume bucket and hydraulic arms which can raise and lower the bucket, thus making it useful for scooping up earth and loading it into trucks, these are known as a Drott, trackscavator or track loader.
Other modifications to the original bulldozer include making it smaller to let it operate in small work areas where movement is limited, such as in mining. Some lightweight form of bulldozer are used in snow removal and as a tool for preparing winter sports areas for ski and snowboard sports. A small light bulldozer is sometimes called a "calfdozer". In an angledozer the blade can be pushed forward at one end to make it easier to push material away to the side; the original earthmoving bulldozers are still irreplaceable as their tasks are concentrated in deforestation, ground levelling, road carving. Heavy bulldozers are employed to level the terrain to prepare it for construction; the construction, however, is done by small bulldozers and loader tractors. Bulldozers employed for combat engineering roles are fitted with arm
Armoured fighting vehicle
An armoured fighting vehicle is an armed combat vehicle protected by armour combining operational mobility with offensive and defensive capabilities. AFVs can be tracked. Main battle tanks, armoured cars, armoured self-propelled guns, armoured personnel carriers are all examples of AFVs. Armoured fighting vehicles are classified according to their intended role on the battlefield and characteristics; the classifications are not absolute. For example lightly armed armoured personnel carriers were superseded by infantry fighting vehicles with much heavier armament in a similar role. Successful designs are adapted to a wide variety of applications. For example, the MOWAG Piranha designed as an APC, has been adapted to fill numerous roles such as a mortar carrier, infantry fighting vehicle, assault gun; the concept of a mobile and protected fighting unit has been around for centuries. Armoured fighting vehicles were not possible until internal combustion engines of sufficient power became available at the start of the 20th century.
Modern armoured fighting vehicles represent the realization of an ancient concept - that of providing troops with mobile protection and firepower. Armies have deployed war cavalries with rudimentary armour in battle for millennia. Use of these animals and engineering designs sought to achieve a balance between the conflicting paradoxical needs of mobility and protection. Siege engines, such as battering rams and siege towers, would be armoured in order to protect their crews from enemy action. Polyidus of Thessaly developed a large movable siege tower, the helepolis, as early as 340 BC, Greek forces used such structures in the Siege of Rhodes; the idea of a protected fighting vehicle has been known since antiquity. Cited is Leonardo da Vinci's 15th-century sketch of a mobile, protected gun-platform; the machine was to be mounted on four wheels which would be turned by the crew through a system of hand cranks and cage gears. Leonardo claimed: "I will build armored wagons which will be invulnerable to enemy attacks.
There will be no obstacle which it cannot overcome." Modern replicas have demonstrated that the human crew would have been able to move it over only short distances. Hussite forces in Bohemia developed war wagons - medieval weapon-platforms - around 1420 during the Hussite Wars; these heavy wagons were given protective sides with firing slits. Heavy arquebuses mounted on wagons were called arquebus à croc; these carried a ball of about 3.5 ounces. The first modern AFVs were armed cars, dating back to the invention of the motor car; the British inventor F. R. Simms designed and built the Motor Scout in 1898, it was the first armed, petrol-engine powered vehicle built. It consisted of a De Dion-Bouton quadricycle with a Maxim machine gun mounted on the front bar. An iron shield offered some protection for the driver from the front, but it lacked all-around protective armour; the armoured car was the first modern armoured fighting vehicle. The first of these was the Simms' Motor War Car, designed by Simms and built by Vickers, Sons & Maxim in 1899.
The vehicle had Vickers armour 6 mm thick and was powered by a four-cylinder 3.3-litre 16 hp Cannstatt Daimler engine giving it a maximum speed of around 9 miles per hour. The armament, consisting of two Maxim guns, was carried in two turrets with 360° traverse. Another early armoured car of the period was the French Charron, Girardot et Voigt 1902, presented at the Salon de l'Automobile et du cycle in Brussels, on 8 March 1902; the vehicle was equipped with a Hotchkiss machine gun, with 7 mm armour for the gunner. Armoured cars were first used in large numbers on both sides during World War I as scouting vehicles. In 1903, H. G. Wells published the short story "The Land Ironclads," positing indomitable war machines that would bring a new age of land warfare, the way steam-powered ironclad warships had ended the age of sail. Wells' literary vision was realized in 1916, amidst the pyrrhic standstill of the Great War, the British Landships Committee, deployed revolutionary armoured vehicles to break the stalemate.
The tank was envisioned as an armoured machine that could cross ground under fire from machine guns and reply with its own mounted machine guns and cannons. These first British heavy tanks of World War I moved on caterpillar tracks that had lower ground pressure than wheeled vehicles, enabling them to pass the muddy, pocked terrain and slit trenches of the Battle of the Somme; the tank proved successful and, as technology improved. It became a weapon that could cross large distances at much higher speeds than supporting infantry and artillery; the need to provide the units that would fight alongside the tank led to the development of a wide range of specialised AFVs during the Second World War. The Armoured personnel carrier, designed to transport infantry troops to the frontline, emerged towards the end of World War I. During the first actions with tanks, it had become clear that close contact with infantry was essential in order to secure ground won by the tanks. Troops on foot were vulnerable to enemy fire, but they could not be transported
A storm is any disturbed state of an environment or in an astronomical body's atmosphere affecting its surface, implying severe weather. It may be marked by significant disruptions to normal conditions such as strong wind, hail and lightning, heavy precipitation, heavy freezing rain, strong winds, or wind transporting some substance through the atmosphere as in a dust storm, sandstorm, etc. Storms have the potential to harm lives and property via storm surge, heavy rain or snow causing flooding or road impassibility, lightning and vertical wind shear. Systems with significant rainfall and duration help alleviate drought in places. Heavy snowfall can allow special recreational activities to take place which would not be possible otherwise, such as skiing and snowmobiling; the English word comes from Proto-Germanic *sturmaz meaning "noise, tumult". Storms are created when a center of low pressure develops with the system of high pressure surrounding it; this combination of opposing forces can create winds and result in the formation of storm clouds such as cumulonimbus.
Small localized areas of low pressure can form from hot air rising off hot ground, resulting in smaller disturbances such as dust devils and whirlwinds. There are many varieties and names for storms: Blizzard — There are varying definitions for blizzards, both over time and by location. In general, a blizzard is accompanied by gale-force winds, heavy snow, cold conditions; the temperature criterion has fallen out of the definition across the United States Bomb cyclone - A rapid deepening of a mid-latitude cyclonic low-pressure area occurring over the ocean, but can occur over land. The winds experienced during these storms can be as powerful as that of a hurricane. Coastal Storm — large wind waves and/or storm surge that strike the coastal zone, their impacts include coastal erosion and coastal flooding Derecho — A derecho is a widespread, long-lived, straight-line wind storm, associated with a land-based, fast-moving group of severe thunderstorms. Dust devil — a small, localized updraft of rising air.
Dust storm - A situation in which winds pick up large quantities of sand or soil reducing the visibility Firestorm — Firestorms are conflagrations which attain such intensity that they create and sustain their own wind systems. It is most a natural phenomenon, created during some of the largest bushfires, forest fires, wildfires; the Peshtigo Fire is one example of a firestorm. Firestorms can be deliberate effects of targeted explosives such as occurred as a result of the aerial bombings of Dresden. Nuclear detonations generate firestorms. Gale — An extratropical storm with sustained winds between 34–48 knots. Hailstorm — a type of storm that precipitates round chunks of ice. Hailstorms occur during regular thunderstorms. While most of the hail that precipitates from the clouds is small and harmless, there are occasional occurrences of hail greater than 2 inches in diameter that can cause much damage and injuries. Hypercane -a hypothetical tropical cyclone that could form over 50 °C water; such a storm would produce winds of over 800 km/h.
A series of hypercanes may have formed during the astroid or comet impact that killed the non-avian dinosaurs 66 million years ago. Such a phenomenon could occur during a supervolcanic eruption, or extreme global warming. Ice storm — Ice storms are one of the most dangerous forms of winter storms; when surface temperatures are below freezing, but a thick layer of above-freezing air remains aloft, rain can fall into the freezing layer and freeze upon impact into a glaze of ice. In general, 8 millimetres of accumulation is all, required in combination with breezy conditions, to start downing power lines as well as tree limbs. Ice storms make unheated road surfaces too slick to drive upon. Ice storms can vary in time range from hours to days and can cripple small towns and large metropolitan cities alike. Microburst - a powerful windstorm produced during a thunderstorm that only lasts a few minutes. Ocean Storm or sea storm — Storm conditions out at sea are defined as having sustained winds of 48 knots or greater.
Just referred to as a storm, these systems can sink vessels of all types and sizes. Snowstorm — A heavy fall of snow accumulating at a rate of more than 5 centimeters per hour that lasts several hours. Snow storms ones with a high liquid equivalent and breezy conditions, can down tree limbs, cut off power connections and paralyze travel over large regions. Squall — sudden onset of wind increase of at least 16 knots or greater sustained for at least one minute. Thunderstorm -- A thunderstorm is a type of storm that generates both thunder, it is accompanied by heavy precipitation. Thunderstorms occur throughout the world, with the highest frequency in tropical rainforest regions where there are conditions of high humidity and temperature along with atmospheric instability; these storms occur when high levels of condensation form in a volume of unstable air that generates deep, upward motion in the atmosphere. The heat energy creates powerful rising air currents. Cool descending air currents produce strong downdraughts below the storm.
After the storm has spent its energy, the rising currents die away and downdraughts break up the cloud. Individual s
A highway is any public or private road or other public way on land. It is used for major roads, but includes other public roads and public tracks: It is not an equivalent term to controlled-access highway, or a translation for autobahn, etc. According to Merriam Webster, the use of the term predates 12th century. According to Etymonline, "high" is in the sense of "main". In North American and Australian English, major roads such as controlled-access highways or arterial roads are state highways. Other roads may be designated "county highways" in the Ontario; these classifications refer to the level of government. In British English, "highway" is a legal term. Everyday use implies roads, while the legal use covers any route or path with a public right of access, including footpaths etc; the term has led to several related derived terms, including highway system, highway code, highway patrol and highwayman. The term highway exists in distinction to "waterway". Major highways are named and numbered by the governments that develop and maintain them.
Australia's Highway 1 is the longest national highway in the world at over 14,500 km or 9,000 mi and runs the entire way around the continent. China has the world's largest network of highways followed by the United States of America; some highways, like the European routes, span multiple countries. Some major highway routes include ferry services, such as U. S. Route 10. Traditionally highways were used on horses, they accommodated carriages and motor cars, facilitated by advancements in road construction. In the 1920s and 1930s, many nations began investing in progressively more modern highway systems to spur commerce and bolster national defense. Major modern highways that connect cities in populous developed and developing countries incorporate features intended to enhance the road's capacity and safety to various degrees; such features include a reduction in the number of locations for user access, the use of dual carriageways with two or more lanes on each carriageway, grade-separated junctions with other roads and modes of transport.
These features are present on highways built as motorways. The general legal definition deals with right of use not the form of construction. A highway is defined in English common law by a number of similarly-worded definitions such as "a way over which all members of the public have the right to pass and repass without hindrance" accompanied by "at all times". A highway might be open to all forms of lawful land traffic or limited to specific types of traffic or combinations of types of traffic. A highway can share ground with a private right of way for which full use is not available to the general public as will be the case with farm roads which the owner may use for any purpose but for which the general public only has a right of use on foot or horseback; the status of highway on most older roads has been gained by established public use while newer roads are dedicated as highways from the time they are adopted. In England and Wales, a public highway is known as "The Queen's Highway"; the core definition of a highway is modified in various legislation for a number of purposes but only for the specific matters dealt with in each such piece of legislation.
This is in the case of bridges and other structures whose ownership, mode of use or availability would otherwise exclude them from the general definition of a highway, examples in recent years are toll bridges and tunnels which have the definition of highway imposed upon them to allow application of most traffic laws to those using them but without causing all of the general obligations or rights of use otherwise applicable to a highway. Scots law is similar to English law with regard to highways but with differing terminology and legislation. What is defined in England as a highway will in Scotland be what is defined by s.151 Roads Act 1984 as a road, that is:- "any way over which there is a public right of passage and includes the road’s verge, any bridge over which, or tunnel through which, the road passes. In American law, the word "highway" is sometimes used to denote any public way used for travel, whether a "road and parkway". Highways have a route number designated by t
Sod or turf is grass and the part of the soil beneath it held together by its roots or another piece of thin material. In British English, such material is more known as turf, the word "sod" is limited to agricultural senses. Sod is used for lawns, golf courses, sports stadiums around the world. In residential construction, it is sold to landscapers, home builders or home owners who use it to establish a lawn and avoid soil erosion. Sod can be used to repair golf course, or athletic field that has died. Sod is effective in increasing cooling, improving air and water quality, assisting in flood prevention by draining water. Scandinavia has a long history of employing sod roofing and a traditional house type is the Icelandic turf house. Following the passage of the Homestead Act by Congress in 1862, settlers in the Great Plains used sod bricks to build entire sod houses; this was effective because the prairie sod of the Great Plains was so dense and difficult to cut it earned the nickname "Nebraska marble".
Blacksmith John Deere made his fortune when he became the first to make a plow that could reliably cut the prairie sod. Different types of grass used for sod installation Sod is grown on specialist farms. For 2009, the United States Department of Agriculture reported 1,412 farms had 368,188 acres of sod in production, it is grown locally to minimize both the cost of transport and the risk of damage to the product. The farms that produce this grass may have many varieties of grass grown in one location to best suit the consumer's use and preference of appearance, it is harvested 10 to 18 months after planting, depending on the growing climate. On the farm, it undergoes fertilization, frequent mowing and subsequent vacuuming to remove the clippings, it is harvested using specialized equipment, precision cut to standardized sizes. Sod is harvested in small square or rectangular slabs, or large 4-foot-wide rolls. Mississippi State University has developed a hydroponic method of cultivating sod. For the few sod farms that export turf internationally, this soilless sod may travel both lighter and better than traditional sod.
Additionally, since the sod is not grown in soil, it does not need to be washed clean of soil down to the bare roots, so time to export is shortened. In many applications, such as erosion control and athletic fields, immediacy is a key factor. Seed may fail because of drought, it takes some weeks to form a visually appealing lawn and further time before it is robust enough for use. Turf avoids these problems, with proper care, newly laid sod is fully functional within 30 days of installation and its root system is comparable to that of a seeding lawn two or three years older. Sod reduces erosion by stabilizing the soil. Many prized cultivars only reproduce vegetatively, not sexually. Sod cultivation is the only means of producing additional plants. To grow these varieties for sale, turf farms use a technique called sprigging, where harvested sod mats are cut into slender rows and replanted in the field. Tall fescue is a cool-weather group of grasses originating in Europe used as sod, it exhibits moderate tolerance to both drought and cold, as such is popular in inland temperate environments referred to in the turf and landscaping industries as the "transition zone", where summers are too hot for most cool-weather grasses, yet winters are too cold for most warm-weather grasses.
Fescue is well-adapted to clay soils, moderately shade-tolerant, somewhat resistant to disease, yet still vulnerable to brown patch and Fusarium patch. It grows most in spring and fall, required frequent watering during summer. Due to its bunch-type growth habit, it will not spread undesirably or invade adjacent areas once sodded, yet neither will it fill in voids, periodic maintenance may be required to sustain a homogeneous surface, it has poor wear tolerance compared to Bermuda grass, making it less popular for applications such as athletic fields. Fine fescues are less popular as sod than the tall fescues; as their names suggest, they exhibit much thinner leaf blades, tolerate lower mowing heights than the tall fescues. They may be somewhat more resistant to common diseases. Otherwise, their characteristics are similar. Fine Fescues are used in mixtures with other grasses. Bermuda grass is quite used for golf courses and sports fields across the southern portions of the United States, it tolerates a range of climates in the U.
S. from hot and humid lagoons and bays of the Gulf Coast, to the arid expanses of terrain like plains and deserts in the South and lower Midwest. "Established bermuda grass is a network of shoots, rhizomes and crown tissue together that form a dense plant canopy. This dense plant canopy can be used to propagate clonal varieties by sod, plugs; the aggressive and resilient nature of Bermuda grass makes it not only an excellent turfgrass but a challenging and invasive weed in land cultivated for other purposes. Its one noted weakness is its low tolerance of shade. Given the economic importance of Bermuda grass, it has been the subject of numerous studies. Celebration Bermudagrass:'Celebration' is a dark–green, fine–textured, traffic–tolerant cultivar with high recuperative potential and drought t