I'm going to try and talk myself out of aerating in the traditional way each spring. Won't you join me?
Last year I asked "Is Core Aeration a Thing of the Past?" This year I am wondering if solid or core aeration where sand is worked into holes is needed at all? Here I will try and find some reasons why I should and should not aerate my greens in the spring time. Before we start I'll go over the traditional reasons to aerate and then I will discuss why I might be able to get those benefits in different ways.
Traditionally we core aerate to remove organic matter, reduce compaction, increase soil air and increase drainage. That's pretty much it. Core aeration and filing solid holes with sand are two ways to do this but surely there has to be other ways especially with the new developments we have made in the past 10 years or so?
For the past 3 years we have been deep tine aerating our greens in early October. This was because we had developed some troublesome layers that were below the reaches of traditional aerators. These layers were significantly impeding drainage and the result was a lot of difficulty keeping our greens dry. Since then, we have had almost no drainage issues on our 30 year old greens. The only puddling we have seen has been following a 4" rain event in mid December of 2015. Other than that they drain great! So as far as drainage goes I think the regular deep tining should have us covered.
|Now we're talking|
Last year I applied about half as much nitrogen as in any year prior. This was done with the help of the growth potential formula as I shared in my last post. So far in 2016 I have only needed to apply 0.6g n/m2( about 0.13# N/1000 sq. ft.) I have never been a fan of pushing growth around aeration to close up the holes. This seems counter-intuitive to me. Remove organic matter then push growth and consequently build up organic matter in the process? If I only aerate in the fall I am not pressured to get the greens in good playing condition in a short period of time. I can leave the holes open for much longer in the fall thus increasing the benefits of aeration further. If we are producing less organic matter through less growth there should be less need for removing organic matter with core aeration.
I think often we do things in Canada because our neighbors to the south do them. The thing is that a lot of the courses in the USA have growth all winter long and therefore need to aerate a lot more. Is this the case in Canada? Should we base our aeration practices more on how much growth we get based on our specific climates and not as much on what others do in their specific climate?
|Greens growth and mowing data since last aeration. Not much..... Replace basket empties with liters|
| Deep thought of the day; Is the grass greener because of aeration, or is the grass less green because of aeration?|
Preferential flow, it makes you think....
|My new 4L (1 gallon) spray rig.|
|Lots of bentgrass this spring.|
|Dilution is the solution to pollution|
|Despite no aeration, we are able to grow good grass on our fairways during challenging growing conditions (record drought last summer)|
|Next to useless especially on extremely rocky soils.|
Of course there is also the disruption to play in the spring. Just as conditions improve from the winter, we go back to square one. Aerating in the fall is far less disruptive to business as most people are starting to go south and are tired of golf. Why should we disrupt play early in the season when everyone is excited to get out and play if it's not 100% necessary.
|Finally the course has recovered, then why do we rip it up again?|
The biggest reason is that we have always done it this way. Yeah yeah, that's a bad reason but for the most part, we have aerated in the spring, and have lived to golf another day. The big thing here is that we have done it and have managed to keep grass on our greens. Was it because of spring aeration or despite it? I don't know because we have never not done it. Others have but they are few and far between.
So what's the plan? What would I do if I stopped doing my regular spring aeration? Well for now I am thinking of only coring my aprons and approaches. The reason for this is that there is overlap in fertilizer applications on these areas thus more growth and need to remove organic matter. We also want to prevent collar dams from forming as the sand that we do apply gets caught more in the longer grass surrounding the greens leading to buildup. Removing more material than we add will reduce the collar dams over time.
After that we would add a light (but slightly heavier than normal) topdressing followed by a needle tine aeration. Then we would just go ahead as normal. Regular light topdressings every few weeks and needle tine aeration as needed to keep air and water moving through the soil surface. Then a deep tine aeration in the fall.
Or maybe I'll just solid tine them and fill the holes with sand as other have had success doing. It's still disruptive though and has many of the downsides of core aeration except obviously the need to remove the cores.
So if I do in fact decide to not aerate in the traditional way this spring I need to have a plan for if things don't work out. What if I'm totally wrong? When I am working in potentially hazardous areas in Search and Rescue we always like to have an escape route. We never want to commit to something 100%. As time goes on and new information become available we need to keep our options open to stay safe. So what if after skipping aeration this spring things don't work out. Well I can always go more aggressive in the fall. If I am not happy with the way the green perform this year I can double up in the fall. I can also needle tine more frequently through the season if needed. Last year during the extreme drought we only needle tined our greens twice. Even if I have to needle them 5x as much, it doesn't add up to significant labor compared to core aeration and has virtually no disruption on play.