Aeration - Progress and importance

In my first few months interviewing a variety of groundsmen and greenkeepers, it's been good to see that they all have aeration programmes in place throughout the season. Whether they carry out the process internally with their own equipment, or get contractors in, they understand the benefits regular aeration provides turf surfaces.

I had a look back through the Pitchcare website to see if there was any information on the benefits of aeration and what is available, and I picked up on a good article from June 2012 (also featured in Pitchcare Magazine Issue 42 for any of you who have a back catalogue).

So I thought it might be a good time to briefly point out the key benefits of a regular aeration programme, and to look at any new aeration machines that have come onto the market since that article was written and that are making a difference.

Why aerate?

A well-structured soil contains equal volumes of air and water in the pores that lie between the solid matter. Drainage is, basically, water movement down through this pore space. Roots also grow in this pore space. Any compression of the space taken up by air will adversely affect drainage and root development, thus plant health.

Aeration is any mechanical treatment that sustains or increases the airspace within the soil profile, thus producing better drainage and healthier turf. A well-aerated soil will support a strong microbial population, which brings many benefits to grass growth and the digestion of organic matter. The result of compression of the airspace within the soil is known as compaction.

Problems caused by compaction

• Poor drainage
• Weak grass growth
• Shallow root development
• Increased thatch accumulation
• Annual meadow grass (Poa annua) promotion
• An inconsistency of turf vigour, firmness and receptiveness
• Unreceptive soils
• Increased drought stress

Benefits of aeration

• Relieves compaction
• Promotes proliferation and health of beneficial soil microbes
• Increases root development
• Improves drainage
• Promotes healthy strong grass growth
• Improves soil surface drainage (water infiltration)
• Helps to increase soil temperatures
• Increases soil pore space - allows gaseous exchanges in the soil (oxygen in, carbon dioxide out) that improves root growth and development
• Aids integration of topdressings into the soil profile, and the breakdown of thatch/organic matter
• Promotes better surface levels that will increase ball roll/speed.
• Aids surface firmness/dryness, thereby increasing ball bounce and surface grip

How do we aerate?

There is a wide variety and choice of aeration equipment available out there, new and used, providing different tine sizes, operating widths and shattering features that can meet the requirements of any facility.

• Manual methods: hand fork, Sisis Aerdrain Fork and sarrel spiking roller (all available through the Pitchcare website). Ideal for small areas
• Pedestrian aerator/corer machines: lightweight and can be fitted with a variety of tine options, solid/hollow coring tines
• Tractor mounted aerator/corer machines: various sizes available and can be fitted with a variety of tine options, solid/hollow core tines
• Tractor mounted 'verti-drain' type machines: various sizes available, ideal for deep compaction
• Pedestrian 'verti-drain' type machines
• Disc/blade implements (linear aerators): designed to open up the ground and backfill with porous materials
• Pedestrian and tractor mounted compressed air and water injection aerator systems
• Drill and fill techniques

More importantly, do not disturb the playing surface, allowing play to continue after use.

It is essential to use a variety of aeration techniques to prevent pan layers being created. This usually happens if you continue to use the same aeration technique set at the same depth, resulting in a compacted layer forming at the base of the tine or core depth. Most turfgrass managers will use different methods of aeration by changing the depths, size and diameter of tines.

So, what's new?

The most significant progression in the aeration market since 2012, that I can think of, is the Air2G2. I first saw this machine in action whilst in sales in 2013. From the beginning, I was impressed and thought it had a place in the market as it reminded me of the old Robin Dagger I used when I was a greenkeeper at Haydock Park Golf Club, which did an excellent job spot treating heavily compacted areas on the fairways.

Whilst at Oldham Athletic AFC, we invested in this machine as it was lightweight and enabled us to break up compaction deep down when the pitch was too wet for us to get the tractor and verti-drain on the main pitch.

The Air2G2 324 uses three probes to laterally inject pressurised air up to 12-inches beneath the surface of the soil, in a diameter of up to 9 feet, reaching deep into the soil profile. Compacted layers form as a result of foot traffic, mechanical traffic and nature's daily wear and tear. These laterally injected air blasts loosen compacted soil immediately, without any disruption to the surface of the turf or the roots below.

The injected air relieves compaction, increases porosity and enhances respiration which, in turn, allows water to drain quickly and promotes gas exchange. But, most importantly, it does so with little or no disturbance to the turfgrass surface or the roots below and doesn't leave a trace of cores to clean up afterwards.

Using the Air2G2 helps with:

• Compaction: fractures hardpan layers without disruption to roots or playing surfaces
• Porosity: Lateral air injections increase pore space, promote faster drainage and root development
• Respiration: Forces oxygen in and pushes CO2 and other anaerobic gases out for rootzone gas exchange

With frequent use, using the Air2G2 324 creates surfaces that are healthy, firm and ready for play immediately after treatment. Air is everything to anything that lives, and for your soil, it is a breath of fresh air.

Lee Williams, Pitchcare Technical Journalist