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.
Issue link: http://read.dmtmag.com/i/575944
www.stma.org October 2015 | SportsTurf 29 face is evident when runoff, puddling, and/or slow infiltration occur. Water repellency significantly reduces irrigation distribu- tion uniformity. Although not visually evident, the delay in water movement into the soil in an arid environment also causes water loss to evaporation. This water repellency and loss prevents turf from getting the water it needs to survive. It also contributes to wasted water and run-off of soil directed chemicals such as fertilizer and pesticides. Water repellency is at work below the surface as well. Untreated water repellency disrupts uniform downward water movement, causing it to channel unevenly through the pro- file, sometimes referred to as "fingered flow." Again, this leaves some areas of the soil too wet and others too dry, which pre- vents uniform root establishment and turf growth. A proven wetting agent program will improve the relation- ship between water and soil, resulting in more uniform soil moisture, improved turf quality, and safer playing conditions no matter how much (or how little) water is applied. If you have ever had difficulty getting certain areas of a field to absorb water, or if specific areas are always quick to wilt, then you likely have issues with water repellency. Using a wetting agent will help to maintain soils at a consistent volu- metric water content and improve distribution uniformity. Wetting agents encourage a "matrix flow" of water, distribut- ing water and the important inputs it carries more evenly throughout the soil profile. From both an environmental and economic standpoint, water is one of the most important components of turf maintenance plans and budgets. Wetting agents help water penetrate the soil surface and retain moisture in the soil pro- file. By doing so, less water is needed to maintain high quality turf, thus reducing both the environmental and financial costs associated with irrigating. Even in areas where rainfall is abundant or where high efficiency irrigation systems are in place; wetting agents help to maximize water use efficiency by improving distribution uniformity and enhancing water movement through the soil profile. This reduces the amount of water needed during each irrigation cycle and can extend the amount of time between each irrigation event. WHICH WETTING AGENT IS RIGHT FOR YOU? It is important to note that not all wetting agents are the same. Non-ionics are the most common surfactants used in turf- grass management. Numerous surfactant chemistries exist and performance characteristics vary depending on chemical structure and the makeup of your soil. So how do you know which wetting agent is right for you? Rely on data from universities in your geographical area. Local distributors should also be able to tell you the key components in each wetting agent product and how those ingredients work in the soil and at what rate phytotoxicity may occur. As a turfgrass manager your job is to maintain quality turf while being as efficient and cost-effective as possible. Water repellency can make your job more difficult, especially when drought conditions or water use restrictions come into play. Incorporating a wetting agent into your turf management program will decrease the amount of water lost to runoff and evaporation and improve turf quality. If you need assistance determining which wetting agent chemistry is right for you, discuss it with your local distributor or a wetting agent manufac- turer. Most will be able to determine your specific issue and find a wetting agent solution that fits for local growing conditions. FIND A PROGRAM THAT WORKS AND STICK TO IT The key to any successful wetting agent program is to start early and remain on a consistent application schedule. Although wetting agents can help turf recover from existing water repellency issues, instituting a proven program before the development of water repellency can provide a number of benefits. By increasing soil moisture uniformity, wetting agents help to create a healthier and more consistent growing environ- ment. If the growing environment is managed to its peak potential early in the season, turf will be healthier and better able to defend itself when stress and disease pressures kick in. In addition, water and monetary savings produced early in the season can be banked for the late summer months when the need for frequent irrigation becomes greater. ■ ST Thermal imaging shows water moving in a fingered flow through water repellent soil (top) and the desired matrix flow in a non-repellent soil (bottom). FINGERED MATRIX