Technology permits lower, leaner and faster greens

There is no debating the fact that managing golf greens today has changed over the last 25 years. Today, greens management uses technology and years of experience to produce the finest conditioned greens surfaces ever. It wasn’t too many years ago, the 1970s, that we were cutting greens at 3/16 inch and producing speeds of seven feet on the Stimpmeter. Times have changed.

CONSTRUCTION

The greens that superintendents produce today are, in large part, a result of greens construction techniques that have been refined through the years to offer the ultimate in soil physics. The USGA has done an excellent job in continually reviewing and improving their specifications for greens construction. Present specifications are based on scientific laboratory testing, which will ensure that, with proper construction, a green will perform for many years.

With technology, we have also improved the ability to match the proper sand particle sizes of a USGA spec green. Golf course material suppliers now have very sophisticated sand screening and mixing machines. These machines ensure the proper material will be produced and mixed for greens rootzones.

TURFGRASSES

Since the late 1950s, Penncross creeping bentgrass has dominated the bentgrass market. Even with the newer bentgrasses on the market, Penncross is still the world’s top-selling bentgrass, with some 750,000 pounds sold annually. While Penncross still dominates the market, the grass we now play on is one of the biggest changes in greens surfaces. The new “superbents” (As, Gs, L-93, SR1119, etc.) offer finer texture, greater density, upright growth patterns, and the ability to be cut at preferred heights of 1/8 inch and lower. These bents also offer tremendous rooting potential, which translates into a very water-efficient plant.

IRRIGATION

The old design of a common irrigation system that watered both the greens surfaces and the surrounds has been thrown out the door. This may be one of the biggest reasons for improved greens quality. Now we have dedicated greens systems that water the green surface only. Irrigation companies must also be commended for developing very efficient sprinkler heads, along with computerized controls, that offer the greatest of flexibility.

Over-watering was the biggest mistake made when superintendents switched from managing a soil push-up green to managing a sand-based USGA green. The perched water table theory of the USGA green ensures very efficient water usage. This perched water table, along with independent watering systems, has changed the face of watering practices to more of a “fill the glass” approach. For many, this approach means irrigating to fill the rootzone cavity (the glass) to field capacity, plus an additional amount for flushing through positive drainage. Then let the turf dry down the cavity water (drink the glass) to nearly empty and repeat the cycle. This method of watering has produced excellent turfgrass and water conservation results. Many of the past failures of the USGA green have been directly related to over-watering. Now through experience, these over-watering failures have been all but eliminated.

CULTURAL PRACTICES

One big side benefit of the new “superbents” has been the development of equipment that will help manage these new bents, and contribute to maintaining older bents at a higher level. Quad-tine-type aerification setups and machines have been developed by almost all of the major manufactures. These give the superintendent the option to aerify more often with much less intrusion to play. Small 1/4 inch and 5/16 inch tines spaced close at one-inch centers have moved front and center as the preferred method of aerification. Some manufacturers are even developing larger diameter tines, which will fit quad-tine set-ups for a more aggressive approach when needed.

The development of true dethaching units has been very beneficial for managing the thatching potential of these new bents. These machines offer depths of up to 1.5 inches and various blade widths from 1mm to 3mm. The combination of these de-thatching units and quad-tine type aerification units has made thatch management much easier.

When it comes to topdressing, the approach of frequent and light is the present standard. Some clubs use fertilizer-type rotary spreaders with kiln-dried sand, and even green colored sand has been used. This is a far cry from the past where larger machinery was consistently used, and sand applications to greens were only a few times per year.

MOWING AND GREEN SPEED

As mentioned above, it wasn’t that long ago that 3/16 inch was the normal cutting height for greens surfaces. At most golf courses today, 3/16 inch will get you a pink slip. We now see this height on tees, approaches and some fairways. Today, some golf courses are cutting greens below 1/10 inch. The question now becomes, how low can we go? One fact is for sure, we are rapidly approaching the bottom.

There is no question that the need for speed has brought us to these low limits. Whether TV golf or superintendent competition is responsible for lower cutting heights, speed is here to stay. When determining the perfect speed, a variety of input should be considered, from green design to playability, to name a few. The best way might be to follow the model of Mike Morris, superintendent at Crystal Downs Country Club in Michigan.

FERTILIZATION PRACTICES

Fertilization practices are also evolving. There is no doubt that the biggest management changes in this area are less nitrogen and the use of foliar products. Application amounts of nitrogen per thousand square feet have gone down consistently through the years, and now are in the 1-4#N/M range per growing season. The most popular method of fertilizing has changed from granular application to foliar feeding programs. The spoon-feeding (light and frequent) approach is certainly the en vogue method. Even though foliar is the hot topic for fertilizing, kudos must be given to the fertilizer manufacturers. They have produced some great fertilizer materials, with extremely small particle size, that work very well with the new, denser bents.

SEEDING VS. SODDING

For years, seeding had been the preferred method for greens establishment and sodding was labeled taboo. However, in recent years sodding greens has made major gains over seeding. These gains have been made primarily because of the ability of the sod producers to grow excellent sod quality and address the layering phenomena. In the past, failures from sodded greens have been mostly related to an incompatible match of the rootzone mix with the sod medium. Presently, sod is even being grown on plastic. When harvested, the roots stay completely intact, suffer less shock, and have very fast rooting potential.

LOOKING TO THE FUTURE

No one can predict the future, but we certainly can guess what it holds. Are we at the ultimate in greens management? Maybe. Can the height of cut be dropped much lower? Probably not. However, years ago, Penncross was considered the ultimate, as was 5/32 of an inch and 10 feet on the Stimpmeter. So who knows, anything could be possible 10 years from now.