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/391471
www.stma.org October 2014 | SportsTurf 9 accordingly. Using ET is only effective if you know your precipita- tion rates of your irrigation system. TDR soil moisture probes or TDR soil moisture readers that are placed into the soil permanently are great at giving you an idea of how much moisture is in the soil. Every soil is different, so it takes a little work to understand how to use this effectively to set up irriga- tion. You will need to figure out what moisture level is Wilting Point and Field Capacity. This doesn't have to be perfect, but getting this close is very helpful. Drying down the field until it wilts and then measuring the moisture level will give you an idea of what Wilting Point is for that soil. Field capacity is the amount of water the soil holds in its microp- ore spaces within the soil. This is when the soil is slightly damp and water can be squeezed out of the soil with a little effort. Again you want to be close, not perfect. If you know what field capacity and wilting point for your field are than you can target your irrigation cycles to be somewhere in between those two values. If you irrigate much more than field capacity you could be wasting water going through the soil profile quicker than the plant can use it or its running off the surface in a saturated state. In the real world we probably irrigate slightly above field capacity, but are really just try- ing to keep the soil at field capacity. Understanding your precipitation rates for your irrigation system is very important. I won't be able to give a lot of detail on this in this article for the sake of length, but figuring out how many inches an hour your system irrigates is very important when understanding how to schedule your run times. If you don't know your precipitation rates than you're just guessing with your run times. Guessing could lead to over or under irrigating. Either way it's not an efficient use of water. Auditing your irrigation system isn't terribly difficult if you wanted to do it yourself or there are companies that could do it for you (see SportsTurf August 2014 issue, page 30 on how to conduct an irrigation audit). Sometimes spending some money on the front end can save you money on the back end. If you understand and use ET, TDR probes, and precipitation rates you would absolutely be justified in using the water you do to deliver safe and healthy athletic fields. There are other things like rain sensors and central irrigation that can help make you more efficient as well. The point to all the irrigation tools is to help you conserve water. Remember, you're conversationalists even if you didn't know it. Ask yourself if you do everything you can to conserve water, even if it's readily available. There are times for playability you may abuse water, but that should only be justified for player safety. The rest of the time you should be trying to conserve as much water as possible.