A lawn is an area of aesthetic and recreational land planted with grasses or other durable plants, which usually are maintained at a low and consistent height. Low ornamental meadows in natural landscaping styles are a contemporary option of a lawn. In recreational contexts, the specialised names turf, pitch, field or green may be used, depending on the sport and the continent.
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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.
Seasonal lawn establishment and care varies depending on the climate zone and type of lawn grown.
Early autumn, spring, and early summer are the primary seasons to seed, lay sod, plant 'liners', or 'sprig' new lawns, when the soil is warmer and air cooler. Seeding is the least expensive, but takes longer for the lawn to establish; deeper rooting, though, can make for a more durable lawn. Aerating just before planting/seeding will promote deeper root growth and will help thicken turf.
Sodding provides an almost 'instant lawn', and can be planted in most temperate climates in any season, but is more expensive and more vulnerable to drought. 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.
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. [1][1] The Ontario provincial government promised on September 24, 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.[2] On April 22, 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.[3] The Ontario legislation would also echo Massachusetts law requiring pesticide manufacturers to reduce the toxins they use in production.[4]
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 insecticide alternative example is applying beneficial nematodes to combat grubs. The Integrated Pest Management approach is a coordinated low impact approach.[5]
Maintaining a rough lawn requires only occasional cutting with a suitable machine, or grazing by animals. Social pressure from neighbors and local municipal ordinances commonly require homeowners to keep grass cut.[6]
Summer lawn care requires raising the lawn mower for cool season grasses, and lowering it for warm season lawns. Lawns will require longer and more frequent watering, best done in early morning to encourage a stronger root system. This is also the time to apply an all-purpose fertilizer. During the hot summer months, lawns may be susceptible to fungal disease. It is advisable to take a sod sample to a local landscape expert for testing and treating the yard, if necessary.
In the autumn, lawns can be mowed at a lower height, and 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 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.
Maintaining high visibility lawns may require special maintenance procedures:
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,[7] 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 practiced 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.
It was not until the Tudor and Elizabethan times 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.
In the early 18th century, landscape gardening entered another design style. William Kent and Lancelot "Capability" Brown brought the landscape garden style into popularity. Lawns appeared to flow from the garden into the outer reaches of the estate landscape. 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.
In the 1870s, lawns began to appear beyond affluent properties and city parks. Most people had neither the hired labor nor leisure time to cut a field of grass with scythes, and most raised vegetables and flowers. During the Victorian era, as more plants were introduced and available horticulturally in Europe, lawns became smaller, as flower beds were created and filled with perennials, sculptures, and water features. At the end of the 19th century, suburban development with land around residences began. With sprinkler technology, improved and mass-produced lawn mowers, new expectations about gardens, and a shorter working week, lawns came of age in the U.S. and northern Europe. Through the 20th century, western landscape influence brought the lawn to many parts of the world.
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.
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.
Many different species of grass are 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[8] 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.
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.[9] They retain their color well in extreme cold and typically grow very dense, carpetlike lawns with relatively little thatch.
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).
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.[10]
Some lawns are replaced with low ground covers, such as creeping thyme, camomile, Lippia, purple flowering Mazus, grey Dymondia, creeping sedums, and creeping jenny.[12] 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.
Concerns, criticisms, and ordinances regarding lawns come from the environmental consequences:
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.[13] A 2005 NASA study found over 30 million acres (120,000 km2) of irrigated lawn in the US (128,000 km2 or 12,800,000 hectares), three times the area of irrigated corn.[15]
“ | 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. | ” |
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.[16]
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.[17][18]
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.
Wikisource has the text of the 1920 Encyclopedia Americana article Lawns. |