Natural turf

Typical static friction coefficients are given in Table 1. These data demonstrate that the absolute traction values for synthetic surfaces are satisfactory in comparison with natural turf, provided that shoes with the appropriate surfaces are employed. Synthetic surfaces by virtue of their constmction are to a degree directional, a characteristic which, when substantial, can significantly affect both player performance and ball roU. This effect is evident in a measurement of shoe traction in various directions with respect to the turf—pile angle. Some traction characteristics are directiy affected by the materials. 

Abrasions occur most commonly from generalized trauma or friction of skin against equipment, mats, or turf. More abrasions occur with artificial than natural turf because of its enhanced surface friction and harder quality (Freeman and Bergfeld 1977). Clinically, the abrasion appears as a localized, crusted, or weeping erosion. 

Jones, P.L., Kerwin, D.C., Irwin, C., and Nokes, L.D.M., Three dimensional analysis of knee biomechanics when landing on natural turf and football turf. /. Med. Biol. Eng., pp. 184-188,2009. 

For example, consider Techturf, a rugged, natural turf system for golf courses that is based on a PP-mesh reinforcement from BriAg Industries Ltd., a York-based subsidiary of ICI Plastics. It consists of a sand and fertilizer growing medium held together with 2-... 

In the United States the analytical methods approved by most states are ones developed under the auspices of the Association of Official Analytical Chemists (AOAC) (3). Penalties for analytical deviation from guaranteed analyses vary, even from state to state within the United States (4). The legally accepted analytical procedures, in general, detect the solubiUty of nitrogen and potassium in water and the solubiUty of phosphoms in a specified citrate solution. Some very slowly soluble nutrient sources, particularly of nitrogen, are included in some specialty fertilizers such as turf fertilizers. The slow solubihty extends the period of effectiveness and reduces leaching losses. In these cases, the proportion and nature of the specialty source must be detailed on the labeling. 

A grass-like artificial surface was installed for the first time in 1964, at Moses Brown School (Providence, Rhode Island) (1). In 1966, artificial turf was installed in the Houston Astrodome in Texas. These surfaces consisted of green pigmented, nylon-6,6 pile ribbon, with a cross-section resembling that of natural grass. Since that period, other fabrics of various pile ribbon and constmctions have continued to become available commercially for indoor and outdoor facihties. 

By way of comparison, for natural grass playing fields in late autumn ranges from about 75 for wet fields to 280 for fro2en turf (8). The intermediate values observed depend on soil type, moisture, condition, and other variables. 

Chou CH, Patrick ZA (1976) Identification and phytotoxic activity of compounds produced during decomposition of com and rye residues in soil. J Chem Ecol 2 369-387 Christians NE (1993) The use of com gluten meal as a natural preemergence weed control in turf. Int Turfgrass Society Res J 7 284—290... 

Green, G. A. (1988). Living on borrowed turf. Natural History 97,58-64. 

These needs led in turn to investigation of ways of preparing synthetic surfaces so that in behaviour they would be very similar to natural lawn or turf. The factors examined in this connection included the heights to which sports balls would rebound, the resistance to balls rolled over the surface ( ball drag ), and the absorption of impact. All were found to depend largely on the method of construction of the synthetic surface, including its underlayers—the correct... 

The various fungicides have either specific or broad spectrum efficacy. These can be deployed for either prophylactic or curative action. Beyond the farm crops and horticulture, maintenance of turf and lawns free of insects and weeds, and the preservation of natural and agricultural forestry are significant markets for insecticides and herbicides. 

Factors controlling N2 fixation in reef environments have been considered in several recent studies. WiUiams and Carpenter (1998) investigated the importance of natural water flow on nitrogenase activity associated with algal turfs of coral reef environments and found a positive correlation between flow and activity. Higher activity was associated with oscillatory flow compared to unidirectional flow. 

Chemicals and other agents (biological, physical), both natural and man-made, may be released into the environment as a result of their production and use and, through dispersion and transport processes, may be present in food, water, soil, indoor and outdoor air, and other media (e.g., residential turf, indoor carpet, clothing). Thus, humans may be exposed to these agents by one or more routes (ingestion, inhalation, dermal absorption) and from one or more... 

Funk CR, White JF Jr. Use of natural and transformed endophytes for turf improvement. In Hill N, Bacon CW, eds. Endophyte/Grass Interactions. New York Plenum, 1997. 

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