lawn

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WordNet

1. a field of cultivated and mowed grass
2. not properly maintained or cared for; "an unkempt garden"; "native vistas and unkempt rambling paths"; "an ukempt appearance"
3. not neatly combed; "wild unkempt hair"
4. lawn grass common in China and Japan; grown also in United States (同)Japanese lawn grass, Zoysia japonica
5. a bowling game played on a level lawn with biased wooden balls that are rolled at a jack (同)bowls
6. garden tool for mowing grass on lawns (同)mower
7. the learned profession that is mastered by graduate study in a law school and that is responsible for the judicial system; "he studied law at Yale" (同)practice of law
8. the collection of rules imposed by authority; "civilization presupposes respect for the law"; "the great problem for jurisprudence to allow freedom while enforcing order" (同)jurisprudence
9. a generalization that describes recurring facts or events in nature; "the laws of thermodynamics" (同)law of nature
10. a rule or body of rules of conduct inherent in human nature and essential to or binding upon human society (同)natural_law
11. legal document setting forth rules governing a particular kind of activity; "there is a law against kidnapping"
12. the syllable naming the sixth (submediant) note of a major or minor scale in solmization (同)lah

PrepTutorEJDIC

1. 『芝生』[『地』]
2. ローン(ハンカチ・ブラウスなどに用いるごく薄地のリネンまたは木綿布)
3. (髪が)くしを入れてない,もどゃもどゃの / (服装・外見などが)だらしがない
4. (特に芝生コートで行う)テニス,庭球
5. 芝刈り機
6. 〈U〉《the ~》《集合的に》(法律・法規を総称して)『法』 / 〈U〉〈C〉(個々の)『法律』,法規 / 〈U〉法の[統制]力 / 〈U〉法律学 / 〈U〉弁護士[業] / 〈U〉《the law》警察[力],警官(police) / 〈U〉法の適用(発動);訴訟(legal action) / 〈C〉(科学・芸術などでの)法則,きまり / 〈C〉〈U〉(一般に従うべき)おきて,ならわし,規則
7. ラ(全音階の第6音)

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出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2015/05/24 03:22:20」(JST)

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"Lawns" redirects here. For other uses, see Lawns (disambiguation).

For other uses, see Lawn (disambiguation).

Lawn facing the west frontage of the German Reichstag in Berlin.

The lawn of a small summerhouse.

A croquet lawn at a club in Edinburgh, Scotland

San Francisco Botanical Garden Lawn

A lawn is an area of land planted with grasses or (rarely) other durable plants, which are maintained at a short height and used for aesthetic and recreational purposes. Common characteristics of a lawn are that it is composed only of grass species, it is subject to weed and pest control, it is subject to practices aimed at maintaining its green color, and it is regularly mowed to ensure an acceptable length, although these characteristics are not binding as a definition. In recreational contexts, the specialised names turf, pitch, field or green may be used, depending on the sport and the continent.

The term "lawn", referring to a managed grass space, dates to no earlier than the 16th century. Tied to suburban expansion and the creation of the household aesthetic, the lawn is an important aspect of the interaction between the natural environment and the constructed urban and suburban space.

Etymology

Lawn is a cognate of llan which is derived from the Common Brittonic word landa (Old French: launde) that originally means heath, barren land, or clearing.

History

Origins

Gardens of the Château de Vaux-le-Vicomte, designed by André Le Nôtre at Versailles.

Lawns may have originated as grassed enclosures within early medieval settlements used for communal grazing of livestock, as distinct from fields reserved for agriculture. The word "laune" is first attested in 1540, and is likely related to the Celtic Brythonic word lan/llan/laun, which has the meaning of enclosure, often in relation to a place of worship.

Lawns became popular with the aristocracy in northern Europe from the Middle Ages onward. The early lawns were not always distinguishable from pasture fields. It is speculated the association between the word "pasture" and biblical mentions made lawns a cultural affinity for some. The damp climate of maritime Western Europe in the north made lawns possible to grow and manage. They were not a part of gardens in other regions and cultures of the world until contemporary influence.

Before the invention of mowing machines in 1830, lawns were managed very differently. They were an element of wealthy estates and manor houses, and in some places were maintained by the labor-intensive methods of scything and shearing. In most situations, they were also pasture land maintained through grazing by sheep or other livestock. Areas of grass grazed regularly by rabbits, horses or sheep over a long period often form a very low, tight sward similar to a modern lawn. This was the original meaning of the word "lawn", and the term can still be found in place names. Some forest areas where extensive grazing is practno

iced still have these seminatural lawns. For example, in the New Forest, England, such grazed areas are common, and are known as lawns, for example Balmer Lawn. Lawns similar to those of today first appeared in France and England in the 1700s when André Le Nôtre designed the gardens of Versailles that included a small area of grass called the "tapis vert" or "green carpet".

The English lawn

Capability Brown's landscape design at Badminton House.

It was not until the 17th and 18th century, that the garden and the lawn became a place created first as walkways and social areas. They were made up of meadow plants, such as camomile, a particular favorite. In the early 17th century, the Jacobean epoch of gardening began; during this period, the closely cut "English" lawn was born. By the end of this period, the English lawn was a symbol of status of the aristocracy and gentry; it showed that the owner could afford to keep land that was not being used for a building, or for food production.

In the early 18th century, landscape gardening for the aristocracy entered into a golden age, under the direction of William Kent and Lancelot "Capability" Brown. They refined the English landscape garden style with the design of natural, or "romantic", estate settings for wealthy Englishmen. Brown, remembered as "England's greatest gardener", designed over 170 parks, many of which still endure. His influence was so great that the contributions to the English garden made by his predecessors Charles Bridgeman and William Kent are often overlooked.

His work still endures at Croome Court (where he also designed the house), Blenheim Palace, Warwick Castle, Harewood House, Bowood House, Milton Abbey (and nearby Milton Abbas village), in traces at Kew Gardens and many other locations. His style of smooth undulating lawns which ran seamlessly to the house and meadow, clumps, belts and scattering of trees and his serpentine lakes formed by invisibly damming small rivers, were a new style within the English landscape, a "gardenless" form of landscape gardening, which swept away almost all the remnants of previous formally patterned styles. His landscapes were fundamentally different from what they replaced, the well-known formal gardens of England which were criticised by Alexander Pope and others from the 1710s.

1803 painting of the main elements of the English landscape garden.

The open "English style" of parkland first spread across Britain and Ireland, and then across Europe, such as the Garden à la française being replaced by the French landscape garden. By this time, the word "lawn" in England had semantically shifted to describe a piece of a garden covered with grass and closely mown. Wealthy families in America during the late 18th century also began mimicking English landscaping styles. In 1780, the Shakers began the first industrial production of high-quality grass seed in North America, becoming a primary supplier as there were few other competing companies. The increased availability of these grasses meant they were in plentiful supply for parks and residential areas, not just livestock.

Thomas Jefferson has long been given credit for being the first person to attempt an English-style lawn at his estate, Monticello, in 1806, but many others had tried to emulate English landscaping before he did. Over time, an increasing number towns in New England began to emphasize grass spaces. Many scholars link this development to the romantic and transcendentalist movements of the 19th century. These green commons were also heavily associated with the success of the Revolutionary War and often became the homes of patriotic war memorials after the Civil War ended in 1865.

Middle class pursuit

The lawn at Kirkby Fleetham Hall, Yorkshire, circa 1889.

Before the mechanical lawnmower, the upkeep of lawns was only possible for the extremely wealthy estates and manor houses of the aristocracy. Labor-intensive methods of scything and shearing the grass were required to maintain the lawn in its correct state, and most of the land in England was required for more functional, agricultural purposes.

This all changed with the invention of the lawnmower by Edwin Beard Budding in 1830. Budding had the idea for a lawnmower after seeing a machine in a local cloth mill which used a cutting cylinder (or bladed reel) mounted on a bench to trim the irregular nap from the surface of woollen cloth and give a smooth finish. Budding realised that a similar device could be used to cut grass if the mechanism was mounted in a wheeled frame to make the blades rotate close to the lawn's surface. His mower design was to be used primarily to cut the lawn on sports grounds and extensive gardens, as a superior alternative to the scythe, and he was granted a British patent on 31 August 1830.

In an agreement between John Ferrabee and Edwin Budding, Ferrabee paid the costs of development and acquired rights to manufacture, sell and license other manufacturers in the production of lawn mowers. Budding went into partnership with a local engineer, John Ferrabee, and together they made mowers in a factory at Thrupp near Stroud. They allowed other companies to build copies of their mower under license, the most successful of these, was Ransomes, Sims & Jefferies of Ipswich which began mower production as early as 1832.

The first gasoline-powered lawnmower, 1902.

However, his model had two crucial drawbacks. It was immensely heavy (it was made of cast iron) and difficult to manoeuvre in the garden, and did not cut the grass very well. The blade would often spin above the grass uselessly. It took ten more years and further innovations, including the advent of the Bessemer process for the production of the much lighter alloy steel and advances in motorization such as the drive chain, for the lawnmower to become a practical proposition. Middle-class families across the country, in imitation of aristocratic landscape gardens, began to grow finely trimmed lawns in their back gardens.

In the 1850s, Thomas Green of Leeds introduced a revolutionary mower design called the Silens Messor (meaning silent cutter), which used a chain to transmit power from the rear roller to the cutting cylinder. The machine was much lighter and quieter than the gear driven machines that preceded them, and won first prize at the first lawn mower trial at the London Horticultural Gardens. Thus began a great expansion in the lawn mower production in the 1860s. James Sumner of Lancashire patented the first steam-powered lawn mower in 1893. Around 1900, Ransomes' Automaton, available in chain- or gear-driven models, dominated the British market. In 1902, Ransomes produced the first commercially available mower powered by an internal combustion gasoline engine. JP Engineering of Leicester, founded after World War I, invented the first riding mowers.

From the 1860s, the cultivation of lawns, especially for sports, became a middle-class obsession in England. Pictured, a lawnmower advertisement from Ransomes.

This went hand-in-hand with a booming consumer market for lawns from the 1860s onward. With the increasing popularity of sports in the mid-Victorian period, the lawn mower was used to craft modern-style sporting ovals, playing fields, pitches and grass courts for the nascent sports of football, lawn bowls, lawn tennis and others. The rise of Suburbanisation in the interwar period was heavily influenced by the garden city movement of Ebenezer Howard and the creation of the first garden suburbs at the turn of the 20th century. The garden suburb, developed through the efforts of social reformer Henrietta Barnett and her husband, exemplified the incorporation of the well manicured lawn into suburban life. Suburbs dramatically increased in size. Harrow Weald went from just 1,500 to over 10,000 while Pinner jumped from 3,00 to over 20,000. During the 1930s, over 4 million new suburban houses were built and the 'suburban revolution' had made England the most heavily suburbanized country in the world by a considerable margin.

Lawns began to proliferate in America from the 1870s onwards. As more plants were introduced from Europe, lawns became smaller as they were filled with flower beds, perennials, sculptures, and water features. Eventually the wealthy began to move away from the cities into new suburban communities. In 1856, an architectural book was published to accompany the development of the new suburbia that placed importance on the availability of a grassy space for children to play on and a space to grow fruits and vegetables that further imbued the lawn with cultural importance. Lawns began making more appearances in development plans, magazine articles, and catalogs. The lawn became less associated with being a status symbol, instead giving way to a landscape aesthetic. Improvements in the lawn mower and water supply enabled the spread of lawn culture from the Northeast to the South where the grass grew more poorly. This in combination with setback rules which required all homes to have a 30-foot gap between the structure and the sidewalk meant that the lawn had found a specific place in suburbia.

American lawn culture

Lawn seating

A Memorial Day concert on the west lawn of the U.S. Capitol Building

A pivotal factor in the spread of the lawn in America, was the passage of legislation in 1938 of the 40 hour work week. Until then, Americans had typically worked half days on Saturdays, leaving little time to focus on their lawns. With this legislation and the housing boom following the Second World War, managed grass spaces became more commonplace. The creation in the early 20th century of country clubs and golf courses completed the rise of lawn culture.

Levittown, New York was the beginning of the industrial suburb in the 20th Century, and by proxy the industrial lawn. Between 1947 and 1951, Abraham Levitt and his sons built more than seventeen thousand homes, each with its own lawn. Abraham Levitt wrote "No single feature of a suburban residential community contributes as much to the charm and beauty of the individual home and the locality as well-kept lawns". Landscaping was one of the most important factors in Levittown's success - and no feature was more prominent than the lawn. The Levitts understood that landscaping could offset the normal depreciation of a home, adding to the appeal of their developments. During 1948, the first spring that Levittown had enjoyed, Levitt and Sons fertilized and reseeded all of the lawns free of charge.

Lawn monoculture was a reflection of more than an interest in offsetting depreciation, it propagated the homogeneity of the suburb itself. Levittown is widely regarded by scholars as the birthplace of the conveyor belt style, mass-produced suburb that is now quite common. Although lawns had been a recognizable feature in English residences since the 19th century, a revolution in industrialization and monoculture of the lawn since the Second World War fundamentally changed the ecology of the lawn. Intensive suburbanization both concentrated and expanded the spread of lawn maintenance which meant increased inputs in not only petrochemicals, fertilizers, and pesticides, but also natural resources like water.

Front lawns became standardized in the 1930s when, over time, specific aspects such as grass type and maintenance methods became popular. The lawn-care industry boomed, but the Great Depression of the 1930s and in the period prior to World War II made it difficult to maintain the cultural standards that had become heavily associated with the lawn due to grass seed shortages in Europe, America's main supplier. Still, seed distributors such as Scotts Miracle-Gro Company in the United States encouraged families to continue to maintain their lawns, promoting it as a stress-relieving hobby. During the war itself, homeowners were asked to maintain the appearances of the home front, likely as a show of strength, morale, and solidarity. After World War II, the lawn aesthetic once again became a standard feature of North America, bouncing back from its minor decline in the decades before with a vengeance, particularly as a result of the housing and population boom post-war.

The G.I. Bill in the United States let American ex-servicemen buy homes without providing a down payment, while the Federal Housing Administration offered lender inducements that aided the reduction of down payments for the average American from 30% to as little as 10%. These developments made owning your own home cheaper than renting, further enabling the spread of suburbia and its lawns.

The economic recession that began in 2008 has resulted in many communities worldwide to dig up their lawns and plant fruit and vegetable gardens. This has the potential to greatly change cultural values attached to the lawn, as they are increasingly viewed as environmentally and economically unviable in the modern context.

Australia

The appearance of the lawn in Australia followed closely after its establishment in North America and parts of Europe, likely due in part to the continued influence of colonial powers. By the 1920s, this "nature strip" was common throughout the developing suburbs of Australia as a result of increased globalization and industrialization. This term is uniquely Australian, alluding, perhaps, to man's desire to control nature. Prior to the 1970s, all brush and native species were stripped from a development site and replaced with lawns that utilized imported plant species. However, since the 1970s there has been a resurgence in Australian patriotism and nationalism, leading to a rejection of imported European or North American plant life in favor of indigenous species.

Over time, with consideration to the frequency of droughts in Australia, the movement towards "naturalism", or the use of indigenous plant species in yards, was beneficial. These grasses were more drought resistant than their European counterparts, and those families who wished to keep their lawns switched to these alternatives. Many suburban homes completely gave up on trying to maintain a lawn and instead allowed their green carpets to revert to the indigenous scrub that had been there before in an effort to reduce the strain on water supplies.

Uses

A newly seeded, fertilized and mowed lawn

Lawns are a common feature of private gardens, public landscapes and parks in many parts of the world. They are created for aesthetic pleasure, as well as for sports or other outdoor recreational use. Lawns are useful as a playing surface both because they mitigate erosion and dust generated by intensive foot traffic and because they provide a cushion for players in sports such as rugby, football, soccer, cricket, baseball, golf, tennis, hockey and lawn bocce.

Types of lawn plants

Lawns need not be, and have not always been, made up of grasses alone. Other plants for lawn-like usable garden areas are sedges, low herbs and wildflowers, and ground covers that can be walked upon.

The area on the right has not been mown since the previous autumn.

Thousands of varieties of grasses and grasslike plants are used for lawns, each adapted to specific conditions of precipitation and irrigation, seasonal temperatures, and sun/shade tolerances. Plant hybridizers and botanists are constantly creating and finding improved varieties of the basic species and new ones, often more economical and environmentally sustainable by needing less water, fertilizer, pest and disease treatments, and maintenance. The three basic categories are cool season grasses, warm season grasses, and grass alternatives.

Grasses

History of the grasses used in lawns

Prior to European colonization, the grasses on the East Coast of North America were mostly broom straw, wild rye, and marsh grass. As Europeans moved into the region, it was noted by colonists in New England, more than others, that the grasses of the New World were inferior to those of England and that their livestock seemed to receive less nutrition from it. In fact, once livestock brought overseas from Europe spread throughout the colonies, much of the native grasses of New England disappeared, and an inventory list from the 17th century noted supplies of clover and grass seed from England. New colonists were even urged by their country and companies to bring grass seed with them to North America. By the late 17th century, a new market in imported grass seed had begun in New England.

Much of the new grasses brought by Europeans spread quickly and effectively, often ahead of the colonists. One such species, Bermuda grass (Cynodon dactylon), became the most important pasture grass for the southern colonies.

Kentucky Bluegrass (Poa pratensis) is a grass native to Europe or the Middle East. It was likely carried to Midwestern United States in the early 1600s by French missionaries and spread via the waterways to the region around Kentucky. However, it may also have spread across the Appalachian mountains after an introduction on the east coast. Kentucky Bluegrass is now one of the top three pasture grasses in the United States and the most desirable species of grass for lawns.

Farmers at first continued to harvest meadows and marshes composed of indigenous grasses until they became overgrazed. These areas quickly fell to erosion and were overrun with less favorable plant life. Soon, farmers began to purposefully plant new species of grass in these areas, hoping to improve the quality and quantity of hay to provide for their livestock as native species had a lower nutritive value. While Middle Eastern and Europeans species of grass did extremely well on the East Coast of North America, it was a number of grasses from the Mediterranean that dominated the Western seaboard. As cultivated grasses became valued for their nutritional benefits to livestock, farmers relied less and less on natural meadows in the more colonized areas of the country. Eventually even the grasses of the Great Plains were overrun with European species that were more durable to the grazing patterns of imported livestock.

Many different species of grass are currently used, depending on the intended use and the climate. Coarse grasses are used where active sports are played, and finer grasses are used for ornamental lawns for their visual effects. Some grasses are adapted to oceanic climates with cooler summers, and others to tropical and continental climates with hotter summers. Often, a mix of grass or low plant types is used to form a stronger lawn when one type does better in the warmer seasons and the other in the colder ones. This mixing is taken further by a form of grass breeding which produces what are known as cultivars. A cultivar is a cross-breed of two different varieties of grass and aims to combine certain traits taken from each individual breed. This creates a new strain which can be very specialised, suited to a particular environment, such as low water, low light or low nutrient.

Diagram of a typical lawn grass plant.

Cool season grasses

Cool season grasses start growth at 5 °C (41 °F), and grow at their fastest rate when temperatures are between 10 °C (50 °F) and 25 °C (77 °F), in climates that have relatively mild/cool summers, with two periods of rapid growth in the spring and autumn. They retain their color well in extreme cold and typically grow very dense, carpetlike lawns with relatively little thatch.

• Conventional selections:
  • Bluegrass (Poa spp.)
  • Bentgrass (Agrostis spp.)
  • Ryegrasses (Lolium spp.)
  • Fescues (Festuca spp., hybrids, and cultivars)

• Native plant regional selections (for taller lawns):
  • Red fescues (Festuca rubra)
  • Feather reed grass (Calamogrostis spp.)
  • Tufted hair grass (Deschampsia spp.)
  • Cluster fescue (Festuca_paradoxa spp.)

Warm season grasses

Warm season grasses only start growth at temperatures above 10 °C (50 °F), and grow fastest when temperatures are between 25 °C (77 °F) and 35 °C (95 °F), with one long growth period over the spring and summer (Huxley 1992). They often go dormant in cooler months, turning shades of tan or brown. Many warm season grasses are quite drought tolerant, and can handle very high summer temperatures, although temperatures below −15 °C (5 °F) can kill most southern ecotype warm season grasses. The northern varieties, such as buffalograss and blue grama, are hardy to 45 °C (113 °F).

• Zoysiagrass (Zoysia spp.)
• Bermudagrass (Cynodon spp.)
• St. Augustine grass
• Bahiagrass (Paspalum)
• Centipedegrass (Eremachloa)
• Carpetgrass (Axonopus)
• Buffalograss (drought tolerant)
• Grama grass

Grass alternatives

Carex species and cultivars are well represented in the horticulture industry as 'sedge' alternatives for 'grass' in mowed lawns and garden meadows. Both low growing and spreading ornamental cultivars and native species are used in for sustainable landscaping as low maintenance and drought tolerant grass replacements for lawns and garden meadows. wildland habitat restoration projects and natural landscaping and gardens use them also for 'user friendly' areas. The J. Paul Getty Museum has used Carex pansa (meadow sedge) and Carex praegracilis (dune sedge) expansively in the Sculpture Gardens in Los Angeles.

Some lower sedges used are:

• Carex caryophyllea (cultivar 'The Beatles')
• C. divulsa (Berkeley sedge)
• C. glauca (blue sedge) (syn. C. flacca)
• C. pansa (meadow sedge)
• C. praegracilis (dune sedge)
• C. subfusca (mountain sedge)
• C. tumulicola (foothill sedge) (cultivar 'Santa Cruz Mnts. selection')
• C. uncifolia (ruby sedge)

Ground cover alternatives

Some lawns are replaced with low ground covers, such as creeping thyme, camomile, Lippia, purple flowering Mazus, grey Dymondia, creeping sedums, and creeping jenny. Other alternatives to lawns include meadows, drought tolerant xeriscape gardens, natural landscapes, native plant habitat gardens, paved Spanish courtyard and patio gardens, butterfly gardens, rain gardens, and kitchen gardens. Trees and shrubs in close proximity to lawns provide habitat for birds in traditional, cottage and wildlife gardens.

Lawn care and maintenance

Seasonal lawn establishment and care varies depending on the climate zone and type of lawn grown.

Planting and seeding

Broadcast spreaders can be attached to tractors or ATVs to spread seed or fertilizer

Aeration is one method used to maintain a lawn

Early autumn, spring, and early summer are the primary seasons to seed, lay sod (turf), plant 'liners', or 'sprig' new lawns, when the soil is warmer and air cooler. Seeding is the least expensive, but may take longer for the lawn to be established. Aerating just before planting/seeding may promote deeper root growth and thicker turf.

Sodding (American English), or turfing (British English), provides an almost instant lawn, and can be undertaken in most temperate climates in any season, but is more expensive and more vulnerable to drought until established. Hydroseeding is a quick, less expensive method of planting large, sloped or hillside landscapes. Some grasses and sedges are available and planted from 'liner' and 4-inch (100 mm) containers, from 'flats', 'plugs' or 'sprigs', and are planted apart to grow together.

Lawn growth, 20 hour time lapse

Fertilizers and chemicals

Various organic and inorganic or synthetic fertilizers are available, with instant or time-release applications. Pesticides, which includes biological and chemical herbicides, insecticides and fungicides are available. Consideration for their effects on the lawn and garden ecosystem and via runoff and dispersion on the surrounding environment, can constrain their use. For example, the Canadian province of Quebec and over 130 municipalities prohibit the use of synthetic lawn pesticides. In order for the lawn to grow and flourish, the soil must be prepared properly. If this step is overlooked as many do, the lawn will burn out as soon as it runs out of nutrients. The Ontario provincial government promised on 24–2 September, 2007 to also implement a province-wide ban on the cosmetic use of lawn pesticides, for protecting the public. Medical and environmental groups support such a ban. On 22–2 April, 2008, the Provincial Government of Ontario announced that it will pass legislation that will prohibit, province-wide, the cosmetic use and sale of lawn and garden pesticides. The Ontario legislation would also echo Massachusetts law requiring pesticide manufacturers to reduce the toxins they use in production.

Sustainable gardening uses organic horticulture methods, such as organic fertilizers, biological pest control, beneficial insects, and companion planting, among other methods, to sustain an attractive lawn in a safe garden. An example of an organic herbicide is corn gluten meal, which releases an 'organic dipeptide' into the soil to inhibit root formation of germinating weed seeds. An example of an organic alternative to insecticide use is applying beneficial nematodes to combat soil-dwelling grubs, such as the larvae of chafer beetles. The Integrated Pest Management approach is a coordinated low impact approach.

Mowing and other maintenance practices

A typical lawn mowing bot maintaining even and low grass.

Dethatching removes dead grass and decomposing materials that build up in a lawn

Lawn sweepers clean up debris from dethatching in addition to leaves, twigs, pine needles, etc.

Maintaining a rough lawn requires only occasional cutting with a suitable machine, or grazing by animals. Maintaining a smooth and closely cut lawn, be it for aesthetic or practical reasons or because social pressure from neighbors and local municipal ordinances requires it, necessitates more organized and regular treatments. Usually once a week is adequate for maintaining a lawn in most climates. However, in the hot and rainy seasons of regions contained in hardiness zones greater than 8, lawns may need to be maintained up to two times a week.

Summer lawn care requires raising the lawn mower for cool season grasses, and lowering it for warm season lawns. In order to remain green (prevent dormancy), grass lawns will require longer and more frequent watering, best done in early morning or evening to reduce evaporation. When grass is actively growing is also the time to apply an all-purpose fertilizer.

In the autumn, thatch buildup that occurs in warm season grasses should be removed, although lawn experts are divided in their opinions on this. This is also a good time to add a sandy loam top dressing and apply a fertilizer containing some type of wetting agent. Cool season lawns can be planted in autumn if there is adequate rainfall.

Lawn care in the winter is minimal, requiring only light feedings of organic material, such as green-waste compost, and minerals to encourage earthworms and beneficial microbes.

Maintenance of high visibility lawns may incorporate special maintenance procedures:

• Mowing regularly with a sharp blade at an even height
• Not mowing when the lawn is wet
• Removing no more than 30% of the plant tissue in any one cut
• Alternating the direction of cut from the previous mowing
• Scarifying/dethatching and sweeping/raking (to remove dead grass, leaves, and other debris, and to prevent tufting)
• Rolling, to encourage tillering (branching of grass plants) and to firm the ground (for sports use only)
• Top dressing with sand, soil or other material
• Aeration with a spike aerator or plug/core aerator (to relieve compaction of the soil and allow greater absorption of nutrients)
• Seeding to cover patchy areas and maintain thick turf

Social impacts

The prevalence of the lawns in films such as Pleasantville and Edward Scissorhands alludes to the importance of the lawn as a social mechanism that gives great importance to visual representation of the American suburb as well as its practised culture. It is implied that a neighbor, whose lawn is not in pristine condition, is morally corrupt, emphasizing the role a well-kept lawn plays in neighborly and community relationships. In both of these films, green space surrounding a house in the suburbs becomes an indicator of moral integrity as well as of social and gender norms as lawn care has long been associated with men. These lawns also reinforce class and societal norms by subtly excluding minorities who may not have been able to afford a house in the suburbs with a lawn that was the symbolic representation of safety and stability. The lawn as a reflection of someone's character and the neighborhood at large is not restricted to films, the same theme is evident in The Great Gatsby, a book written by American novelist F. Scott Fitzgerald. Character Nick Carraway rents the house next to Gatsby's and fails to maintain his lawn according to West Egg standards. The rift between the two lawns troubles Gatsby to the point that he dispatches his gardener to mow Nick's grass and thereby create uniformity.

Most lawn care equipment over the decades has been advertised to men, and companies have long associated good lawn care with good citizenship in their marketing campaigns. As well, the appearance of a healthy lawn was meant to imply the health of the man taking care of it; controlled weeds and strict boundaries became a practical application of the desire to control nature, as well as an expression of control over their personal lives once working full-time became central to suburban success. Women were encultured over time to view the lawn as part of the household, as an essential furnishing, and to encourage their husbands to maintain a lawn for the family and community reputation.

During World War II, women became the focus of lawn-care companies in the absence of their husbands and sons. The lawn was promoted as a necessary means by which women could help support their male family members and American patriotism as a whole. The image of the lawn changed from focusing on technology and manhood to emphasizing aesthetic pleasure and the health benefits derived from its maintenance; it was assumed that women would not respond positively to images of efficiency and power. The language of these marketing campaigns still intended to imbue the female population with notions of family, motherhood, and the duties of a wife; it has been argued that this was done so that it would be easier for men returning from war to resume the roles their wives had taken over in their absence. This was especially apparent in the 1950s and 1960s, when lawn-care rhetoric emphasized the lawn as a husband's responsibility and as a pleasurable hobby when he retired.

The lawn aesthetic in Europe and Australia seems to exhibit the same cultural tendencies as a representation of order, power over nature, patriotism, and suburban family life while still adhering to other gender constructs present throughout the world's suburbs. However, there are differences in the particulars of lawn maintenance and appearance, such as the length of the grass, species (and therefore its color), and mowing.

Environmental concerns

Greater amounts of chemical fertilizer and pesticides are used per acre of lawn than on an equivalent acre of cultivated farmland, and the continued use of these products has been associated with environmental pollution, disturbance in the lawn ecosystem, and increased health risks to the local human population.

Other concerns, criticisms, and ordinances regarding lawns come from the environmental consequences:

• Some lawns are composed of a monoculture (single species) of plants, which reduces biodiversity, especially when the lawn covers a large area. They usually are composed of introduced species not native to the area, which can further decrease a locale's biodiversity and vital habitats supporting an ecosystem.
• Lawn maintenance may use inorganic fertilizers, synthetic pesticides, herbicides, and fungicides, which can harm the environment. The United States Environmental Protection Agency has estimated nearly 70,000,000 pounds (32,000,000 kg) of active pesticide ingredients are used on suburban lawns each year in the United States. It has also been estimated that more herbicides are applied per acre of lawn than are used by most farmers to grow crops.
  • For example, Sweden, Denmark, Norway, Kuwait, and Belize have placed restrictions on the use of the herbicide 2,4-D.
• It has been estimated that nearly 17 million gallons of gasoline are spilled each summer while re-fueling garden and lawn-care equipment in the United States; approximately 50% more than that spilled during the Exxon Valdez incident.
• The use of pesticides and fertilizers, requiring fossil fuels for manufacturing, distribution, and application, have been shown to contribute to global warming, whereas sustainable organic techniques have been shown to help reduce global warming.

A lawn sprinkler

Water conservation

Maintaining a green lawn sometimes requires large amounts of water. This was not a problem in temperate England, where the concept of the lawn originated, as natural rainfall was sufficient to maintain a lawn's health. The exportation of the lawn ideal to more arid regions of the world, however, such as the U.S. Southwest and Australia, has crimped already scarce water resources in such areas, requiring larger, more environmentally invasive water supply systems. Grass typically goes dormant during cold, winter months, and turns brown during hot, dry summer months, thereby reducing its demand for water. Many property owners consider this "dead" appearance unacceptable, and therefore increase watering during the summer months. Grass can also recover quite well from a drought.

In the United States, 50 to 70% of residential water is used for landscaping, most of it to water lawns. A 2005 NASA study "conservatively" estimated there was 128,000 square kilometres (49,000 sq mi; 32,000,000 acres) of irrigated lawn in the US, three times the area of irrigated corn.

“ That means about 200 gallons of fresh, usually drinking-quality water per person per day would be required to keep up our nation's lawn surface area. ”

It is possible that lawn maintenance could come at the expense of precious resources, especially when faced with extreme weather conditions. This situation is described in Water in Australia by David Ingle Smith, who observed in 1995 data that under extreme conditions during summer drought periods, up to 90% of the water used in Canberra, Australia was applied to lawns.

Chemicals

An increased concern from the general public over pesticide and fertilizer use and their associated health risks, combined with the implementation of the Food Quality Protection Act, has resulted in the reduced presence of synthetic chemicals, namely pesticides, in urban landscapes such as lawns in the late 20th century. Much of these concerns over the safety and environmental impact of some of these synthetic fertilizers and pesticides has led to their ban by the United States Environmental Protection Agency and many local governments. The use of pesticides and other chemicals to care for lawns has also lead to the death of nearly 7 million birds each year, a topic that was central to Silent Spring by Rachel Carson.

Decreasing environmental impact

In the United States, lawn heights are generally maintained by gasoline-powered lawnmowers, which contribute to urban smog during the summer months. The EPA found, in some urban areas, up to 5% of smog was due to small gasoline engines made before 1997, such as are typically used on lawnmowers. Since 1997, the EPA has mandated emissions controls on newer engines in an effort to reduce smog.

A 2010 study seemed to show lawn care inputs were balanced by the carbon sequestration benefits of lawns, and they may not be contributors to anthropogenic global warming.

However, lawns with high maintenance (mowing, irrigation, and leaf blowing) and high fertilization rates have a net emission of carbon dioxide and nitrous oxide that have large global warming potential.

With the use of ecological techniques including organic lawn management, the impact of lawns can be reduced. Such methods include the use of native grasses, sedges, and low herbs; higher mowing techniques; low volume irrigation, 'grasscycling' grass clippings in place; an integrated pest management program; exclusive organic fertilizer and compost use; and including a variety of trees, shrubs, perennials, and other plants surrounding the lawn. A positive benefit of a healthy lawn is it filters contaminants and prevents runoff and erosion of bare soil.

In addition to the environmental criticisms, some gardeners question the aesthetic value of lawns, especially in climates and cultures different from the lawn's homeland in England.

See also

Lawns

• Grasses
• Grasslands
• Lawn topics
• Lawn sweeper
• Lawn aerator
• Organic lawn management

Gardening

• Gardening
• Organic gardening
• Organic horticulture
• Sustainable gardening
• Sustainable landscaping
• List of organic gardening and farming topics with links

Others

• bacterial lawn

References

Further reading

• Bormann, F. Herbert, et al. (1993) Redesigning the American Lawn.
• Huxley, A., ed. (1992). New RHS Dictionary of Gardening. Lawns: Ch. 3: pp. 26–33. Macmillan. ISBN 0-333-47494-5.
• Jenkins, V. S. (1994). The Lawn: A History of an American Obsession. Smithsonian Books. ISBN 1-56098-406-6.
• Steinberg, T. (2006). American Green, The Obsessive Quest for the Perfect Lawn. W.W. Norton & Co. ISBN 0-393-06084-5.
• Wasowski, Sally and Andy (2004). Requiem for a Lawnmower.

External links

• "Planting and care of Lawns" from the UNT Govt. Documents Dept.
• Integrated Pest Management Program: website & search-engine
• Lawn Care University at Michigan State University
• "EPA Management of Polluted Runoff: Nonpoint Source Pollution" (includes mismanagement of lawns problems.)
• "MSU Turfgrass Disease Identification Tool (turf disease identification & research resource.)

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Related Links

• Lawn | Definition of Lawn by Merriam-Webster

Middle English launde, from Anglo-French land, launde wood, unwooded field, of Celtic origin; akin to Middle Irish lann land — more at land First Known Use: 14th ... Seen and Heard What made you want to look up lawn? Please tell ...

• Lawn - definition of lawn by The Free Dictionary

lawn 1 (lôn) n. A plot of grass, usually tended or mowed, as one around a residence or in a park. [Alteration of Middle English launde, glade, from Old French, heath, pasture, wooded area; see lendh-in Indo-European roots.] lawn 2 (lôn)

• lawnの意味・用例｜英辞郎 on the WEB：アルク

lawn 【1名】芝生、芝地 【2名】ローン生地 【語源】フランスの都市Laonから ... - アルクがお届けする進化するオンライン英和・和英辞書データベース。一般的な単語や連語から、イディオム、専門用語、スラングまで幅広く収録。

Related Pictures

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★リンクテーブル★

リンク元	「unkempt」「菌叢」
関連記事	「law」

「unkempt」

　　[★]

• adj.

• 1.not combed: unkempt hair. 　←　櫛を入れていない、もじゃもじゃの、ぼさぼさの
• 2.uncared-for or neglected; disheveled; messy: unkempt clothes; an unkempt lawn. 　←　だらしのない、きちんとしていない(服装、外見、芝生)
• 3.unpolished; rough; crude.　←　粗野な、洗練されない

　 　 　

「菌叢」

　　[★]

英

bacterial lawn、lawn

「law」

　　[★]

• n.

• 法、法律

関

jurisprudence、litigation、method