WATERING DIFFICULT AREAS

For areas under and near trees, you need to know the water requirements for the specific trees as well as for the turfgrass. Despite having deep "anchor" roots, trees take up moisture and nutrients from the top 6 inches (15 cm) of soil—the same section of the soil used by turfgrass roots. Tus the trees and turfgrass will compete for water. Watering sufficiently for the grass may over water some varieties of trees and under water others. Core aeration, the use of a surfactant, and the same methods of slow, small area irrigation used for slopes may work to resolve these issues in some situations.

Watering difficult areas requires special attention to achieve maximum benefit and a beautiful lawn. Proper watering practices improve the quality of your lawn, provide important environmental benefits, and save you money. Because water is a valuable resource, it should be used as efficiently as possible.

Sloped sections of the lawn can be difficult to manage during irrigation. Depending on the degree of slope, runoff may occur before the soil is adequately moist. To conserve water and ensure even irrigation, stop watering if runoff begins. Wait 30 minutes to an hour and then restart watering. Repeat this process as needed to soak the soil to a depth of 4 to 6 inches (10–15 cm).

Some sloping areas may require use of a specialized sprinkler, drip irrigation or a soaker hose. Tese methods of irrigation apply water slowly over a small area to reduce runoff and allow better water penetration into the soil. Tese methods also may be used on small areas of the lawn that are surrounded by hardscape features, next to buildings or walkways, or otherwise difficult to irrigate without wasting water.

Clay soils that absorb water very slowly also can be difficult to irrigate effectively. One technique to improve water infiltration and percolation is core aeration, which creates small holes that make it easier for water to move down into the soil.

A second technique is the use of a surfactant, or wetting agent, which reduces the surface tension of the water. Tis "wetter" water will run more freely into the soil. Apply the surfactant at the manufacturer's recommended rate.

Combining these techniques can be even more effective. Tey also can be used on sloping areas where runoff is a problem.

TPI Turf News July/August 2016 For more information on lawn care and helpful “How to” tips, visit The Lawn Institute at http://www.TheLawnInstitute.org.

If not, a common solution is to not plant turfgrass under the drip-line of trees, instead using that area for other types of perennial groundcovers or for flower beds or simply covering it with mulch.

It can be difficult to provide adequate water to corners and edges of the lawn and areas next to buildings, which are all exposed to reflected heat. Tese areas are more vulnerable to drying out and are easily missed by many sprinklers. Te techniques and irrigation methods recommended for clay soils may provide the solution for these areas.

In some situations, you also may want to syringe

(water lightly) these areas, using the specialized irrigation methods, standard sprinklers, or hand watering, to cool the surface of the turfgrass and/or to provide additional water as needed.

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