DIGGING IN

  • Irrigation puts you in control of the vital, nonrenewable resource that is water.
  • It’s simple: Water is essential for plant growth. Turfgrasses are plants. Turfgrasses provide the playing surface on the majority of athletic fields. Turfgrasses on athletic fields need water
  • The increasing worldwide demand for water, coupled with persistent drought in many regions, equals water restrictions and escalating water costs. In turn, efficient irrigation is an essential component of your field management program.

Different turfgrass species (such as bermudagrass or turf-type tall fescue) and specific cultivars (varieties) within the species have differing water requirements. Select those that are best adapted for your site’s physical and environmental conditions. Overwatering causes problems such as a wet soil surface that’s easily compacted by play or by mowing equipment.

AVAILABLE RESOURCES

MATCH IRRIGATION TO FIELD NEEDS

  • The first step to irrigation efficiency is analyzing your site to establish needs. This starts with the soil, where your turfgrass grows. Soil is made up of rocks, minerals, organic matter and water. Different soil textures are based on the proportion of the three categories of mineral particles they contain: sand (the largest by size), silt (the mid-size) and clay (the smallest). The larger (coarser) particles allow better rates of infiltration (the movement of water into the soil) and penetration (the movement of water within the soil). Coarser, sandy soils have less water-holding capacity than clay soils. Deep and infrequent irrigation typically is the most effective for sandy and sandy loam soils, while lighter, more frequent irrigation is preferred for the finer, more tightly structured clay soils.
  • The layering of soil textures within the soil profile slows water movement because each layer, working from the soil surface down, must be thoroughly saturated before water can move to the next layer. Compaction (compression of the soil) also reduces water penetration and infiltration.
  • Different turfgrass species (such as bermudagrass or turf-type tall fescue) and specific cultivars (varieties) within the species have differing water requirements. Select those that are best adapted for your site’s physical and environmental conditions.
  • As the STMA Water Conservation BMP document states, “The National Turfgrass Evaluation Program (NTEP) provides extensive, reliable information about the performance of quality turfgrass species and cultivars in specific regions of the country.”
  • Determine water availability and quality. Potable (drinkable) water from a public source, such as a city, though normally readily available, is costly and subject to restrictions during drought situations. While nonpotable or recycled water from a public source may be available and is less costly, it often is high in salts. Water from a private well, lake or pond may have quality issues, too. Have all of your water sources tested to better understand how they will impact your turfgrass.
  • Water pressure is another concern, as it governs the ability to deliver the required amount of water to the irrigation location and through the watering device when irrigation is needed. Inadequate water pressure limits irrigation scheduling and can reduce irrigation system performance.
  • Schedule your irrigation to allow for maximum field use. The best time to irrigate turfgrass is just before or right after sunrise, when evaporation rates are minimal and winds are less likely to disrupt the irrigation pattern.

Irrigating athletic fields improves tolerance to insect and disease pressure.

PORTABLE IRRIGATION OPTIONS

  • Multiple-field facilities with limited budgets may use total reliance on natural precipitation for some fields and a variety of irrigation methods on others. In most cases, operation of any irrigation product or system requires installation of a backflow prevention device to guard against contamination of the water source.
  • One of the options is the use of portable sprinklers, which must be manually connected to a water source and put in place for each irrigation cycle. A perforated pipe or hose can be used to provide a continuous spray of water across a long, narrow area. Sprinklers that attach to a hose are available in a wide variety of basic types.
  • Stationary sprinklers are designed for small area irrigation. They cover a preset pattern or, with some, a choice of preset patterns, that may be rectangular, square or circular. They send a continuous spray of water across the designated area.
  • Rotary sprinklers have nozzles at the end of arms that turn in a circular motion, sending a fan of water over the area in the direction the nozzle is facing at that moment.
  • Oscillating sprinklers have a tube or bar that moves back and forth, releasing a gentle arc of water across a designated area, typically rectangular.
  • Pulsating sprinklers have a raised head, mounted on a base, and send a jet of water across a complete circle (or a segment of one). Pulsating sprinklers may be adjustable, with the segment to be covered changed manually, or be preset with full-, half- or quarter-circle coverage.
  • Traveling sprinklers move from one end of an area to the opposite end following a pathway laid out in advance. Though typically rotary, the type of water delivery varies by the sprinkler manufacturer and model. Traveling sprinklers are semi-automatic, generally using water pressure to create the winch-type action that moves them forward and shutting themselves off at the end of their path. They require manual labor to establish the pathway, put the sprinkler in place and start the irrigation cycle.
  • Quick coupler systems utilize a network of permanently installed underground pipes topped in several spots by a ground-level connection point. Quick coupler systems typically are connected to a public water source with sufficient pressure to operate the sprinklers that will be attached to them. The connection point should be secure, requiring a key to turn it on.
  • Someone must still manually connect a water-delivery device to the quick coupler. That could be a hose equipped with a nozzle for short-cycle hand-watering. For longer irrigation cycles, it could be a commercial-grade sprinkler designed for such use, or some sort of hose and sprinkler combination.
  • Drip irrigation slowly releases a precisely measured amount of water through a system of tubes and emitters. Drip irrigation can be portable or permanently installed for landscaped areas. Permanent subsurface drip installations also may be used to irrigate turfgrass sports fields.

Watering reduces dust and improves traction on baseball and softball infields.

INSTALLED IRRIGATION SYSTEMS

  • Irrigation suppliers have made many advances in technology and have developed athletic field-specific products that offer options to improve efficiency that weren’t available previously.
  • Key among the improved system components are smart controllers that can be programmed remotely. They’re capable of receiving and reacting to signals received by devices such as rain sensors, soil moisture sensors and evapotranspiration (ET) rates from on-site or remote weather stations.
  • All the major irrigation companies offer athletic field-specific irrigation system design information on their websites, most in both CAD and PDF formats. These suppliers also provide details on how to incorporate their products into these systems for maximum efficiency in water use.
  • Tap into the expertise of your irrigation sales representative or a certified irrigation specialist. Ask for assistance specific to your site for designing a new system or renovating an existing one.
  • Once installed, monitor the system to detect any areas of potential runoff or overspray onto nonturf surfaces. You want to eliminate any possibility of water waste.

Irrigation suppliers have made many advances in technology and have developed many athletic field-specific products.

Schedule your irrigation to allow for maximum field use. The best time to irrigate turfgrass is just before or right after sunrise, when evaporation rates are minimal and winds are less likely to disrupt the irrigation pattern.