SportsTurf provides current, practical and technical content on issues relevant to sports turf managers, including facilities managers. Most readers are athletic field managers from the professional level through parks and recreation, universities.
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FACILITY & OPERATIONS 42 SportsTurf | February 2015 www.sportsturfonline.com TOOLS & EquIPmENT mulation and irradiance infiltration. These covers may be in-place for a typical period of four to eight days but events lasting up to 20 days are not uncommon. Applying science to the study and use of turf protection is becoming more sophisticated and is providing the type of data that allows the user to make an informed choice of turf protec- tion covers. There are five main types of scientific measurements that have been made to assess the levels of stress on the individual plants. Light energy is necessary for photosynthesis; a critical factor in plant health. In the area of turf protection, translucent covers provide exposure of plants to the sun and photosynthesis. In tandem with light energy is the orientation of the individual leaves. Plant leaves that are nearly vertical only absorb light in the upper part of the leaf. Translucent covers provide the only opportunity for photosynthesis to continue while the turf is being protected. Light quality and light quantity both play an important role in turf health. The growth and development of turf grasses are greatly influenced by the quality and quantity of light available for photosynthesis. Opaque covers do not pro- vide for the absorption of light so leaf quality suffers distress. Multispectral radiometry measures plant light reflectance in the visible and near-infrared ranges and provides an objective method for estimating turf grass quality or green cover. Studies were conducted in growth chambers at the Virginia Bioinformatics Institute facility and in the field at Virginia Tech Turf Grass Research Center. The growth chambers were estab- lished to evaluate two different irradiance and soil moisture conditions. Field studies were conducted in spring, summer and fall with event covers in place from 2 to 20 days. Four covers were evaluated in the growth chamber and in the field: 1) single-layer plywood, 1.9 cm thick opaque cover; 2) plywood with polyester mesh fabric, opaque cover; 3) single-sided plastic, translucent cover; and 4) double-sided plastic, translucent cover. Various combinations of light, moisture and compaction were used to evaluate the turf grasses under different levels of distress all compared to a well-maintained control sample. Field trials were conducted over a 2-year period with two trials of each type of cover in each season of the year; spring, summer, and fall. Temperature, moisture, compaction, light quality and quantity and other factors previously discussed were closely monitored. From the growth chamber and field tests the findings were documented as follows: Turf under the double-sided plastic, translucent cover displayed a lower degree of heat stress symptoms in summer compared to the other covers. The air space between the top sur- face and the solid back acts as an insulator. Both translucent covers maintained the best percent green cover and the calculations predicted that the maximum number of days the turf could be covered and still recover was greater than 20 for both. The double-sided translucent cover allowed for better green cover during high temperature periods when compared to the single-sided translucent cover. Temperatures under the former were up to 30% cooler than latter. Both translucent panels provided long-term protection (>20 days) and turf recovery. But the single-sided model sank into the turf when driven over, resulting in damage to the turf and soil compaction (saturated soil conditions were present at the begin- ning of the 2010 season). The solid back of double-sided model eliminated such "creasing" but matted the turf consistently. The double-sided model provided the advantages of greater protection in summer heat and quality retention in all seasons. The testing program was prepared and conducted by John Paul Royse, submitted as his Master of Science thesis in crop and soil environmental sciences, Virginia Polytechnic Institute and State University, 2012. ■ ST R ay Cipperly is proud of the baseball field he built with students and maintenance staff 40 years ago on the East Brunswick, NJ campus of Middlesex County Vocational Schools. As a physical education teacher and baseball coach at the school, he wanted the stu- Solving poa annua problemS in new JerSey Editor's note: This article was supplied by ClaytonHimes PR on behalf of their client FMC Professional Solutions. Ryan Radcliffe, head groundskeeper, and Ray Cipperly, Athletic Director, Middlesex County Vocational Schools.