Get The Most Bang For Your Buck When Cultivating Greens

By Brian Whitlark, Agronomist, Southwest Green Section
September 28, 2009


The Graden sand injection machine outfitted with 2mm carbide tipped blades affects nearly 7% surface area. The sand injected into the slits firms the surface and expedites turfgrass recovery.

Golfers hate the disruption created following greens cultivation. Their displeasure is understandable, the quality of the putting surface is substantially reduced for period of one to three weeks, depending on how aggressive the cultivation and the health of the turfgrass. Conveying the agronomic benefits of core aeration often falls on deaf ears amongst the golfing crowd. Therefore, when communicating to your golfers, highlight the benefits cultivation provides for the long-term quality of the playing surface:

If core cultivation and thatch reduction tactics are forgone or are significantly reduced, the putting surfaces will be slow, spongy, and not roll true.
Soft, spongy greens resulting from inadequate cultivation efforts are more susceptible to deep pitch marks, further reducing putting quality.
If cultivation efforts fall short of organic matter and thatch production year after year, greens may need resurfacing in 10 years or less, resulting in course closure and substantial economic inputs.

Core cultivation is disruptive, but is an absolute necessity. Minimizing the number of disruptive aeration events is far friendlier to the business of golf than several or more cultivation dates. There is a trend in the industry to aerate three or four times per year with small 1/4 inch or 3/8 inch hollow tines. Although the small tines typically result in faster turfgrass recovery when compared to larger tines, such a strategy requires multiple aeration events to impact a given surface area, and golfers often respond with statements such as, “they are always punching holes in the greens,” or “when will the greens ever be good again?” With this in mind, you may wish to alter your cultivation practices and employ a strategy to minimize aeration procedures, but maximize the surface area affected during each event. Consider the following discussion on modern cultivation practices to get the most out of your aeration dates:

During prime growing season (July/August for bermudagrass, or March-May for bentgrass) use 0.625” OD, carbide-tipped, hollow tines on tight spacing (1.5” by 1.5” or similar). Immediately fill the holes with sand and run the Graden sand injection machine with 2 mm blades set at 0.5 to 0.75” deep. Topdress and roll often in the following weeks to smooth the putting surfaces. Such a double cultivation event may affect 20% surface area (1.5” by 1.5” with 0.625” OD tines affects 13.6% and the Graden with 2 mm blades affects about 6.5%, the sum is roughly 20%).
Another common practice is to double aerate; the first aeration is completed with a deep tine machine such as a Soil Reliever, Vertidrain or Wiedenmann with solid or hollow ¾” tines. A shallow and closely spaced aeration follows the deep tine. This double aeration may affect roughly 10% surface area, depending on the tine size and spacing.

While the new bentgrasses and ultradwarf bermudagrasses offer improved putting surfaces when compared to older varieties, they produce significantly more thatch and organic matter. It is clearly outside the scope of this update to provide all the tools necessary to properly manage such grasses, but hopefully you are able to take advantage of new equipment and techniques that may minimize the number of disruptive core aeration events while maximizing organic matter and thatch removal. Feel free to contact me for questions about your specific situation.

Source: Brian Whitlark, Agronomist, Southwest Region. bwhitlark@usga.org