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Golf course turf is the grass covering golf courses, which is used as a playing surface in the sport of golf. The grass is carefully maintained by a greenskeeper to control weeds, insects and to introduce nutrients such as nitrogen fertilization. The grass is kept at a constant height by mowing.
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Nitrogen is the nutrient required in greatest amount by turfgrass. [1] During an autumn season, rates of nitrogen (N) application should be lowered to consider previous application's residual available nitrate (NO−
3) and mineralization (inorganic N), especially if there is substantial organic matter which releases its supply of sequestered N. [2]
In the spring, heavy nitrogen applications for the first two months caused changes in color, but the nitrogen response by the grass was not maintained and a decrease in color was found as the growing season progressed. Spring fertilization can increase the tiller numbers of the grass compared to fall fertilization. [3]
In the fall, application of nitrogen fertilizer caused improved color retention and early spring coloration. [3] Year-to-year differences in nitrogen loss during the fall result from differences in temperature and precipitation. Lower levels of nitrogen loss during fall were found when it was warmer (more plant uptake) and dryer (less loss due to leaching). [2]
The quality and color of turf will increase[ clarification needed ] with nitrogen application amount. Both of the high rates created darker green turf throughout the duration of the experiment. There is a positive correlation between high levels of nitrogen fertilizer used on turf and turf quality for any level of wear. [4]
Groundwater and air quality should be considered when applying fertilizer and pesticides to turf.
Turf growth at the time of nitrogen application affects nitrate (NO−
3) leaching risk. For example, grass absorbed more N during active growth while uptake was limited in newly seeded turf. [3] In another study, nitrogen applied after 15 September (of a northern-hemisphere autumn) caused relatively little plant growth, resulting in increased NO−
3 - N concentration in percolate water. [2]
Areas made of sod undergo greater leaching than seeded turf plots. [5] They attributed these differences to less root development in sod which resulted in less uptake of N by the plants. They also found that deep- rather than shallow-rooted grasses absorbed nitrogen more effectively. Additionally, the authors found that nitrogen uptake for loamy sand was greater than a sandy loam because the turf rooting systems were denser in the loam sand.
A highly soluble fertilizer, containing nitrogen in its nitrate form, such as ammonium nitrate, can create leaching three to seven times greater than United States Environmental Protection Agency (EPA) limits of (10 ppm) NO3-N during a time of ten to twenty-five days following nitrogen application. [6] Hummel and Waddington, 2001, found that a slow release nitrogen fertilizer application could provide nitrogen over a long duration and keep nitrogen leaching and volatilization[ clarification needed ] losses to a minimum. [7] A further study demonstrated that after fertilizer application, nitrogen losses exceeded EPA limits. [6]
Photoperiod (the length of daylight) affects overall plant uptake. When the length of daylight gets shorter, grass undergoes less photosynthesis and uptakes less nitrogen. [8] To prepare the surface for the following year, high levels of nitrogen application need to be undertaken at the end of the growing season (such as the southern United States[ clarification needed ]) and increase the risk of nitrate leaching. For example, greater water percolate concentrations of NO3 - N resulted from a late autumn application programme during a New England experiment. [2]
A fertilizer or fertiliser is any material of natural or synthetic origin that is applied to soil or to plant tissues to supply plant nutrients. Fertilizers may be distinct from liming materials or other non-nutrient soil amendments. Many sources of fertilizer exist, both natural and industrially produced. For most modern agricultural practices, fertilization focuses on three main macro nutrients: Nitrogen (N), Phosphorus (P), and Potassium (K) with occasional addition of supplements like rock dust for micronutrients. Farmers apply these fertilizers in a variety of ways: through dry or pelletized or liquid application processes, using large agricultural equipment or hand-tool methods.
Eutrophication is the process by which an entire body of water, or parts of it, becomes progressively enriched with minerals and nutrients. It has also been defined as "nutrient-induced increase in phytoplankton productivity". Water bodies with very low nutrient levels are termed oligotrophic and those with moderate nutrient levels are termed mesotrophic. Advanced eutrophication may also be referred to as dystrophic and hypertrophic conditions. Eutrophication in freshwater ecosystems is almost always caused by excess phosphorus.
Fusarium patch is a disease in turf grass settings also called pink snow mold or Microdochium patch. Microdochium nivale is the pathogen that causes this disease in many cool season turf grass species in North America. The white-pink mycelium on infected leaf blades is a distinguishing characteristic of the Microdochium nivale pathogen. Fusarium patch is considered economically important in the turf grass industry because of its tendency to cause significant injury to golf greens, thereby decreasing putting surface quality. Dissimilar from other snow molds, such as gray snow mold, Microdochium nivale does not need snow cover to cause widespread infection.
Plant nutrition is the study of the chemical elements and compounds necessary for plant growth, plant metabolism and their external supply. In its absence the plant is unable to complete a normal life cycle, or that the element is part of some essential plant constituent or metabolite. This is in accordance with Justus von Liebig's law of the minimum. The total essential plant nutrients include seventeen different elements: carbon, oxygen and hydrogen which are absorbed from the air, whereas other nutrients including nitrogen are typically obtained from the soil.
Sod, also known as turf, is grass. When harvested into rolls it is held together by its roots and a thin layer of soil.
Nutrient management is the science and practice directed to link soil, crop, weather, and hydrologic factors with cultural, irrigation, and soil and water conservation practices to achieve optimal nutrient use efficiency, crop yields, crop quality, and economic returns, while reducing off-site transport of nutrients (fertilizer) that may impact the environment. It involves matching a specific field soil, climate, and crop management conditions to rate, source, timing, and place of nutrient application.
Soil acidification is the buildup of hydrogen cations, which reduces the soil pH. Chemically, this happens when a proton donor gets added to the soil. The donor can be an acid, such as nitric acid, sulfuric acid, or carbonic acid. It can also be a compound such as aluminium sulfate, which reacts in the soil to release protons. Acidification also occurs when base cations such as calcium, magnesium, potassium and sodium are leached from the soil.
Fertigation is the injection of fertilizers, used for soil amendments, water amendments and other water-soluble products into an irrigation system.
Human impact on the nitrogen cycle is diverse. Agricultural and industrial nitrogen (N) inputs to the environment currently exceed inputs from natural N fixation. As a consequence of anthropogenic inputs, the global nitrogen cycle (Fig. 1) has been significantly altered over the past century. Global atmospheric nitrous oxide (N2O) mole fractions have increased from a pre-industrial value of ~270 nmol/mol to ~319 nmol/mol in 2005. Human activities account for over one-third of N2O emissions, most of which are due to the agricultural sector. This article is intended to give a brief review of the history of anthropogenic N inputs, and reported impacts of nitrogen inputs on selected terrestrial and aquatic ecosystems.
Sand-based athletic fields are sports turf playing fields constructed on top of sand surfaces. It is important that turf managers select the most suitable type of sand when constructing these fields, as sands with different shapes offer varied pros and cons. Regular maintenance of sand-based athletic fields is just as important as the initial construction of the field. As water and other aqueous solutions are added, a layer of thatch may accumulate on the surface of the turf. There are different ways to manage this level of thatch, however the most common are aeration and vertical mowing.
In agriculture, leaching is the loss of water-soluble plant nutrients from the soil, due to rain and irrigation. Soil structure, crop planting, type and application rates of fertilizers, and other factors are taken into account to avoid excessive nutrient loss. Leaching may also refer to the practice of applying a small amount of excess irrigation where the water has a high salt content to avoid salts from building up in the soil. Where this is practiced, drainage must also usually be employed, to carry away the excess water.
Pythiumdisease, also known as "Pythiumblight," "cottony blight," or "grease spot," is a highly destructive turfgrass disease caused by several different Pythium species. All naturally cultivated cool-season turfgrasses are susceptible to Pythium and if conditions are favorable to Pythium it can destroy a whole turfgrass stand in a few days or less. Pythium favors hot and very humid weather and will usually develop in low areas or swales in the turfgrass.
Agricultural pollution refers to biotic and abiotic byproducts of farming practices that result in contamination or degradation of the environment and surrounding ecosystems, and/or cause injury to humans and their economic interests. The pollution may come from a variety of sources, ranging from point source water pollution to more diffuse, landscape-level causes, also known as non-point source pollution and air pollution. Once in the environment these pollutants can have both direct effects in surrounding ecosystems, i.e. killing local wildlife or contaminating drinking water, and downstream effects such as dead zones caused by agricultural runoff is concentrated in large water bodies.
Filter strips, also referred to as buffer strips, are small, edge-of-field tracts of vegetated land that are used to reduce the contamination of surface water. They are primarily used in agriculture to control non-point source pollution, however, they may also be used to reduce sediment in storm water runoff from construction sites. There are several types of filter strips including vegetative filter strips, forested riparian buffers, and wind buffers. In agriculture, they are highly effective in reducing the concentration of nitrogen (N) and phosphorus (P) in runoff into surface water and are also effective in reducing sediment erosion and removing pesticides. This helps to prevent eutrophication and associated fishkills and loss of biodiversity. The use of filter strips is very common in developed countries and is required by law in some areas. The implementation and maintenance of filter strips is inexpensive and their use has been shown to be cost effective.
Red thread disease is a fungal infection found on lawns and other turfed areas. It is caused by the corticioid fungus Laetisaria fuciformis and has two separate stages. The stage that gives the infection its name is characterised by very thin, red, needle-like strands extending from the grass blade. These are stromata, which can remain viable in soil for two years. After germinating, the stromata infect grass leaf blades through their stomata. The other stage is visible as small, pink, cotton wool-like mycelium, found where the blades meet. It is common when both warmth and humidity are high.
Manure is organic matter that is used as organic fertilizer in agriculture. Most manure consists of animal feces; other sources include compost and green manure. Manures contribute to the fertility of soil by adding organic matter and nutrients, such as nitrogen, that are utilised by bacteria, fungi and other organisms in the soil. Higher organisms then feed on the fungi and bacteria in a chain of life that comprises the soil food web.
Paspalum vaginatum is a species of grass known by many names, including seashore paspalum, biscuit grass, saltwater couch, silt grass, and swamp couch. It is native to the Americas, where it grows in tropical and subtropical regions. It is found throughout the other tropical areas of the world, where it is an introduced species and sometimes an invasive weed. It is also cultivated as a turfgrass in many places.
Necrotic ring spot is a common disease of turf caused by soil borne fungi that mainly infects roots (4). It is an important disease as it destroys the appearance of turfgrasses on park, playing fields and golf courses. Necrotic Ring Spot is caused by a fungal pathogen that is an ascomycete that produces ascospores in an ascocarp (6). They survive over winter, or any unfavorable condition as sclerotia. Most infection occurs in spring and fall when the temperature is about 13 to 28°C (5). The primary hosts of this disease are cool-season grasses such as Kentucky bluegrass and annual bluegrass (6). Once turf is infected with O. korrae, it kills turf roots and crowns. Symptoms of the disease are quite noticeable since they appear as large yellow ring-shaped patches of dead turf. Management of the disease is often uneasy and requires application of multiple controls. The disease can be controlled by many different kind of controls including chemicals and cultural.
This article is about a disease in grasses other than maize, the disease is the same in rice as it is in maize, Corn grey leaf spot
Seventeen elements or nutrients are essential for plant growth and reproduction. They are carbon (C), hydrogen (H), oxygen (O), nitrogen (N), phosphorus (P), potassium (K), sulfur (S), calcium (Ca), magnesium (Mg), iron (Fe), boron (B), manganese (Mn), copper (Cu), zinc (Zn), molybdenum (Mo), nickel (Ni) and chlorine (Cl). Nutrients required for plants to complete their life cycle are considered essential nutrients. Nutrients that enhance the growth of plants but are not necessary to complete the plant's life cycle are considered non-essential. With the exception of carbon, hydrogen and oxygen, which are supplied by carbon dioxide and water, and nitrogen, provided through nitrogen fixation, the nutrients derive originally from the mineral component of the soil. The Law of the Minimum expresses that when the available form of a nutrient is not in enough proportion in the soil solution, then other nutrients cannot be taken up at an optimum rate by a plant. A particular nutrient ratio of the soil solution is thus mandatory for optimizing plant growth, a value which might differ from nutrient ratios calculated from plant composition.