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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 usually maintained by a greenskeeper to control weeds, insects with pesticides, plant fungal diseases with fungicides 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 can cause 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 can be found when it was warmer (more plant uptake) and dryer (less loss due to leaching). [2]
The quality and color of turf can increase[ clarification needed ] depending on nitrogen application amount. high rates create darker green turf. 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]
The antifungal cyproconazole was marketed as early as 1995 for use on sod farms and golf courses. [9]
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 flour 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.
Sod is the upper layer of turf that is harvested for transplanting. Turf consists of a variable thickness of a soil medium that supports a community of turfgrasses.
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.
Milorganite is a brand of biosolids fertilizer produced by treating sewage sludge by the Milwaukee Metropolitan Sewerage District. The term is a portmanteau of the term Milwaukee Organic Nitrogen. The sewer system of the District collects municipal wastewater from the Milwaukee metropolitan area. After settling, wastewater is treated with microbes to break down organic matter at the Jones Island Water Reclamation Facility in Milwaukee, Wisconsin. The byproduct sewage sludge is produced. This is heat-dried with hot air in the range of 900–1,200 °F (482–649 °C), which heats the sewage sludge to at least 176 °F (80 °C) to kill pathogens. The material is then pelletized and marketed throughout the United States under the name Milorganite. The result is recycling of the nitrogen and phosphorus from the waste-stream as fertilizer. The treated wastewater is discharged to Lake Michigan.
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.
Nitrogen's effects on agriculture profoundly influence crop growth, soil fertility, and overall agricultural productivity, while also exerting significant impacts on the environment.
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.
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.
Dollar spot is a fungal disease of turfgrass caused by the four species in the genus Clarireedia, in the family Rutstroemiaceae. The pathogen blights leaf tissues but does not affect turf grass roots or crowns. There is evidence that a fungal mycotoxin produced by the pathogen may cause root damage, including necrosis of the apical meristem in creeping bentgrass. However, the importance of this toxin is unknown and its effects are not considered a direct symptom of dollar spot. The disease is a common concern on golf courses on intensely managed putting greens, fairways and bowling greens. It is also common on less rigorously maintained lawns and recreational fields. Disease symptoms commonly result in poor turf quality and appearance. The disease occurs from late spring through late fall, but is most active under conditions of high humidity and warm daytime temperatures 59–86 °F (15–30 °C) and cool nights in the spring, early summer and fall. The disease infects by producing a mycelium, which can be spread mechanically from one area to another.
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.
Turf melting out is caused by the fungal pathogen Dreschlera poae, in the family Pleosporaceae. It is a common problem on turfgrass and affects many different species. The disease infects all parts of the plant most commonly on golf course roughs, sports fields, and home lawns. There are two stages of the disease: the leaf blade infection and the crown and root infection Melting out occurs during the cool weather of April and May and is encouraged by high nitrogen fertility. The disease is spread by wind-blown or water splashed spores and survive in thatch.
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.
Gray leaf spot (GLS) is a foliar fungal disease that affects grasses. In grasses other than maize it is caused by Pyricularia grisea, which only infects perennial ryegrass, tall fescue, and St. Augustine grass in places with warm and rainy climates.
Zoysia japonica is a species of creeping, mat-forming, short perennial grass that grows by both rhizomes and stolons. It is native to the coastal grasslands of southeast Asia and Indonesia. The United States was first introduced to Z. japonica in 1895. It received its first import from the Chinese region of Manchuria. Today, Z. japonica has become one of the most widely used species of turfgrass in the United States and other countries worldwide such as in Brazil, serving as a close and cheaper alternative to bermudagrass.
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, although some of them, such as silicon (Si), have been shown to improve nutrent availability, hence the use of stinging nettle and horsetail macerations in Biodynamic agriculture. 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.
Aceria cynodoniensis, the bermudagrass mite, is widely distributed, but only infests bermudagrass and its hybrids. It lives and develops under the leaf sheaths of its host plant. Infestations of the mite can cause destructive damage to bermudagrass turf and it is often regarded as a harmful pest.