Fall Agronomic Practices - The Explanations

Fall is a very important time of year for the agronomy staff.  How the golf course looks and performs next season has a lot to do with what we're currently doing right now.  Two of the most important practices taking place on the course right now are aerification and fescue mowing.  Below are a few pictures accompanied by explanations and reasoning behind them to help provide an understanding behind their importance.

Aerification...a dreaded word that nobody wants to hear in the spring and fall. Commonly Superintendents will hear "do you really have to punch right now? The greens are perfect" or "Why do you have to punch holes now, can we wait until later in the year?" or "can we use smaller holes, why so big?" These questions are perfectly understandable and there are agronomic reasons behind them. 

Do you really have to punch right now? - When deciding when to core aerify greens, tees, or fairways the decision is based on reducing the stress window. During the months of June, July, August, and September in Michigan we expect our warmest, most humid weather in addition to the heaviest amount of traffic from both maintenance practices and golfers. Heavy traffic from these things leads to compaction of the soil, limited root growth, and general turf stress.  Compaction also leads less water, oxygen, and nutrient penetration to the root zone. With these things in mind, we generally aim for a spring aerification in the middle of May and our fall aerification in September.

Fairway Core Sample

Can we use smaller holes? Why so big? - Deciding what size holes to punch and the spacing between holes depends on many factors, but the most important factor is thatch removal. "Thatch" is the layer of organic matter that builds over time on top of the soil.  This organic matter build up comes from dead roots, grass clippings, and many other areas. A large amount of thatch on any turf surface can lead to soft, spongy conditions and limits appropriate infiltration of water and nutrients to the healthy root zone. As you can imagine, the more thatch that builds up, the worse the conditions will become.  The removal of this thatch is crucial to maintaining healthy grass on the golf course. Leaving the boring math out of this explanation, we aim to affect 15% of the surface area each year on greens and approximately 7% on fairways and tees.  The size/spacing of tines and frequency of punching are all contributing factors to achieving these percentages.

Fall Fescue Mowing

Fescue mowing is an important part of our fall maintenance program. Mowing fescue areas in the fall reduces weed growth mechanically and helps to thin the dense growth that has built up throughout the year.  Fall is the best time to target weeds in the fescue and reducing the thick top growth allows for a more effective spray application of herbicides.