by Jeff Higgins, Ph.D.
Aerification is one of the most important turfgrass maintenance tasks that golf course superintendents should perform during the growing season. Golfers do not like aerification, nor do they understand the process, the need, or the benefits of this operation.
There are several benefits from aerification: it relieves soil compaction, increases soil aeration (oxygen), removes bad gases, improves turfgrass density, penetrates soil layers, increases water infiltration, stimulates turfgrass growth, and provides a window of opportunity to address soil issues such as high soluble salts and soil pH adjustments.
In addition, core aerification allows golf course superintendents an opportunity to apply slow release potassium to the turfgrass. Potassium is a very important element that is responsible for regulating water content of turfgrass plant cells and increases stress tolerance. Potassium is also a highly water soluble element that is readily leached; therefore, it is difficult to maintain adequate concentrations of potassium in the turfgrass plants.
One of the most effective and efficient uses of a technology that I have ever seen is the use of Polyon 0-0-50 Micro sulfate of potash after core aerification. This program is very simple and leverages the opportunity created from aerification along with the controlled release properties of Polyon.
The recommendation for this application is to perform the core aerification process using a minimum hollow tine size of ½” in diameter. Remove the cores from the surface. Apply Polyon 0-0-50 Micro sulfate of potash at 8 pounds of product per 1,000 square feet (4 Lbs of K per 1,000 square feet). Drag the Polyon 0-0-50 Micro into the open aerification holes using a coco mat or brush. DO NOT use a metal drag as abrasion to the turfgrass leaves can occur and cause damage. Once the Polyon is incorporated into the aerification holes, topdressing sand should be applied to completely fill the holes.
This single application will provide an average weekly release of 0.25 Lb of K per 1,000 square feet for 16 to 22 weeks. One ton of Polyon 0-0-50 Micro will treat 5.7 acres of greens at this recommended rate. This application has proven to be invaluable on creeping bentgrass greens when applied during the last spring aerification prior to the onset of heat stress of summer.
Additional Polyon 0-0-50 Micro can be applied after needle tine or quad tine aerifications. After these small solid tine aerifications are performed, Polyon 0-0-50 Micro should be applied as a surface broadcast application at 2 pounds of product per 1,000 square feet (1 Lb of K per 1,000 square feet). After application, the irrigation heads should be turned on and allowed to “spin” a couple of turns. The Polyon 0-0-50 Micro will disappear into the open aerification holes and no dragging will be needed.
This program is very effective in providing much needed potassium to the turfgrass plants during high stress periods and is very cost effective. I challenge every golf course superintendent in the country to evaluate the cost of this program and give it a try. The best method to monitor the effectiveness of this program is through the use of tissue testing as a quantitative measure. Ideally, the potassium tissue levels should be above 1.5% by weight. Now, this is what Aerifi-K-ation is all about!