Firm and Fast golfing conditions are something that I started providing in 1982 at Rolling Green Golf Club outside of Philadelphia and through the 80s and early 90s in the Western United States at Cherry Hills and Castle Pines. I have experience with both cool and warm season grasses. This discussion is germane to both. Some of you may remember that some players in the 1985 PGA Championship at Cherry Hills thought that the golf course was too firm. The members didn't have much sympathy since other than the greens being a little faster, the firmness of the greens and fairways and the speed of the 0.25 inch fairways (6+ on the stimpmeter) was the same as the members played all summer and fall.
There are two very divergent methods of providing firm and fast. Both methods we shall assume need solid fundamental agronomics when it comes to soil management, cultivation/topdressing, mowing etc. Responsible turf managers are going more and more towards sustainable practices utilizing microbe friendly soil management programs with more compost, natural organic fertilizers, and microbe friendly mined and synthetic products. Balancing soil nutrition through base saturation is a must. The divergence really comes down to irrigation philosophies.
There are those that provide firm and fast by applying a little bit of water each day when it is hot and maybe even syringing on cool season grasses. And then there are those that irrigate deeply and infrequently. Count me in that second group. There was a year in Philadelphia that I watered fairways 11 times in one season. Others watered 11 times in one week. It wasn't a wet year. Can both methods provide firm and fast conditions? Sure, a talented committed Superintendent can provide firm and fast conditions either way.
The big difference is that deep and infrequent irrigation is more natural and provides for healthier turf. How can this be? Have you ever noticed that the day after a heavy rain that the golf course is starting to firm up and that two, three, and four days after the rain the golf course is really getting firm and by that I mean thirty, forty, fifty yards of roll. And soil types don't have to be sandy, this works on clay, silt and sand. The only thing that varies is the amount of water applied and the frequency.
Deep and infrequent irrigation mimics a heavy rainfall. It connects the surface moisture with the subsurface moisture. This allows the tension of the the pull from the soil particles and gravity to allow water to be pulled down and allow the surface to dry from evaporation, transpiration, soil tension, and gravity as opposed to the light frequent irrigation in which the surface dries mostly by evaporation and transpiration. The other thing that occurs with deep and infrequent irrigation is that as water is pulled down by tension and gravity deeper into the soils, air is pulled into and through the turf canopy and soil to replace water going deeper. Plants and soils that receive more atmospheric/soil gas exchange will be healthier and deeper rooted.
The deep and infrequent irrigation philosophy and technique creates a soil that is at field capacity for a shorter period of time over the long run. Irrigation every day typically takes the soil to field capacity each day as it replaces what was lost the previous 24 hours. Field capacity in an ideal soil is when half of the pore spaces are filled with water and half with air. Field capacity is also when soil is at its maximum potential for compaction. The more frequent the soil surface is at field capacity the more prone the soil is to compaction. Another and less noticeable difference between deep and infrequent and shallow and frequent irrigation is that gas transfer through water is much less than through soils. If soils are irrigated every day there will be less gases transferring between the soil and the atmosphere. Soil microbes, especially the good ones, need oxygen; they get oxygen from the atmosphere. If the soil surface is being sealed with water for a period of time every day until it transpires or evaporates, the transfer of gases has been reduced. Less atmospheric gases in the soils means less healthy soils.
Shallow frequent subsistence irrigation can produce firm conditions when talented Superintendents monitor it and manipulate it to the edge. The golf course will be a little moist each morning. It isn't natural, it isn't the way grasses developed, it does create ideal conditions for compaction, it does make an ideal irrigation technique for Poa annua seed germination, it does tend to produce more shallow rooted plants, moist soils transfer heat more rapidly than dry soils, and it may cause the need for syringing during golf. This philosophy cannot be used in high salt/sodic soils or irrigation waters without a deep flushing periodically.
Deep and infrequent irrigation requires that soils be receptive to irrigations of one half to three quarters of an inch in one evening. The golf course will probably be wet the first morning. But from that point forward the ground will get firmer and firmer for days with another irrigation being needed when the root zone is about 40% depleted of moisture. Wetting agents can help reduce the wet morning period of the first day after an irrigation. Deep and infrequent irrigation minimizes the germination of weed seeds including Poa annua because the soil surface isn't re-moistened every day. If you were trying to get Poa annua seeds to germinate, you would irrigate every day and maybe throw in a syringe.
It really all comes down to a commitment to provide firm fast conditions, the way golf was intended to be played. You can clearly come to the conclusion that I believe that deep and infrequent irrigation is the best way to get there. But just get there, however you do it, just do it. Firm and Fast is good for golf and for some odd reason, it seems as if the Firm and Fast crowd, especially the deep and infrequent ones always tend to have less fertilizer and chemical input for some reason.
The site will take you to a great article written by Ed Miller. Ed was the Assistant Superintendent at Cherry Hills and then went on to Desert Forest, Pebble Beach, Desert Highlands, and then ran all of Carefree Resorts' properties before building and owning courses in Texas. You get the idea. Ed clearly expressed the deep and infrequent philosophy in this USGA Green Section publication. Click on the link below and go to page 11 in the March/April issue.