I’m a man that likes to have a purpose (mostly scientific) behind my practices, and aerification is no different. Superintendents across the country break out the old aerifiers every year during the spring on a given date and go through the motions just because it seems like the wise thing to do. Due to the controversy that this work can cause I like to be prepared for the questions and have specific targets. We do a lot of scientific testing through various labs and use a lot of new technology that can help us make decisions. One of the biggest checks we make each year is a physical analysis of the sand profile in our greens. We do this test through the ISTRC (International Sports Turf Research Center). We take samples from 3-4 greens to be analyzed and they give me a report based on the findings. It gives results on infiltration rates, air capacity (pore space), water capacity, bulk density, and organic matter content. Once you become accustomed to reading and understanding the data it can help you make decisions based on what you’ve done in previous years to get to where you are, and what you need to do to make changes to reach your goals.
We have made some nice strides on greens over the last few years to come closer to our goals, but when you are dealing with a living entity you always have work to do each year to maintain. The top 1-1.5” of soil is where we need to concentrate most of our efforts. These ultradwarf bermudagrasses can produce a lot of organic matter as they are vigorous in their growth below the surface. We had greens ranging from 2.95 – 3.55% organic matter (better than 2011) in this range and ideally you would like to see closer to 2.5%. Based on these numbers we are going to try to keep the majority of our corings this year closer to the surface as our numbers below this level are in ideal range. Why do more than you need to?
So, on greens last week we did a number of things to work on that problem. First, we verticut the greens heavily, in a number of directions, to help control grain on the surface and thin out the canopy. We follow that up with a mowing to clean all the debris left behind. Next, we use a deep tine aerifier with a long 10” solid tine (doesn’t pull a core) to reduce compaction on the whole profile that will allow air to the lower portions and open the soil up for better water percolation. We follow this with our fertilizer amendments (based on testing) and a heavy coat of sand that will fill in the holes. Once this is complete, we come behind with our aerifiers that remove a ½” sized hole on a 1.25”x1.5” spacing. Once the cores are cleaned off the greens we start the rolling and dragging operations for a few days to work the sand/fertilizer in the holes and smooth it out. Timely, heavy waterings after each day will help the sand settle and get the plant back to recovery. It sounds like a lot of activity, but all of these processes have been refined over the years to get max recovery in a short amount of time.
We shoot for similar results on our tees as they also have a sandy profile that needs almost as much attention. We go through the same topdress and fertilizer measures that we do on greens. We follow this with the same aerifiers on the same spacings. We finish up with a series of draggings, blowings, and rollings to get the surface back to recovery. The tee boxes are in great shape this year already, and these processes will only enhance that. Again, the process is designed to work on the organic production of the grass with some benefit to surface compaction.
On fairways, we use the same deep tine machine that we have been using for 5-6 years now. It is designed to pull a 1” plug on a 4x4” spacing. We follow this process with a core processor that demolishes the plugs into smaller pieces. We follow this with a verticut to further chop the plugs and work on the grain of the grass at the same time. We mow and blow behind this to finish it off. Considering the amount of debris and soil that is brought up to the soil, the final product is very clean. The fairway process is designed to eliminate surface compaction, work on organic matter (not a huge issue on clay/silt type soils at this point), and open channels for rains and heavy waterings to flush undesired salts through the root zone.
We have also done some slicing of the soils in the roughs and the high traffic areas to alleviate some surface compaction. There are a lot of high traffic areas on the course where heavy cart use can cause damage to turf. This process helps alleviate some of that and gives the turf a chance to recover. There will be some minor scars that should heal about the same time as the other areas aerified. We mow and blow behind this process to help clean it up.
As you can see it was a very busy week on the Member Course, and extremely productive towards great conditions for months to come.