It’s a perfect, sunny morning and you’ve just reached the
first green in regulation. You feel great and you know you’re within birdie
range. Then, you see them, those little holes in the green. Arrggh! They’ve
just aerified the course, and it’s going to ruin your round, right?
Consider also that aerification is merely a short-term
disruption that has long-term benefits for the course. When you see them,
remember that without those little holes, the greens would eventually die.
Preventive maintenance is an integral part of successful
golf course management. Golfers view aerification as an inconvenience that
takes the greens out of play for a day, pulling cores from the greens and
leaving holes that can affect putting for many days before healing. To add insult
to injury, aerification is best done in many parts of the country during
mid-summer, at the height of the playing season and when most greens are in
prime condition.
But a golfer needs to understand how important aerification
is to produce healthy turf.
Aerification achieves three important objectives. It
relieves soil compaction; it provides a method to improve the soil mixture
around the highest part of a green’s roots and it reduces or prevents the
accumulation of excess thatch.
Like so many things, the quality of a good putting green is
more than skin deep. In fact, the condition of a green has a lot to do with
what goes on below the surface. In order for grass to grow at 1/8” inch, it
must have deep, healthy roots. Good roots demand oxygen. In good soil, they get
the oxygen from tiny pockets of air trapped between soil and sand particles.
Over time, the traffic from golfers’ feet (as well as mowing
equipment) tends to compact the soil under the putting green – particularly
when the soil contains a lot of clay. When soil becomes compacted, the air
pockets on which the roots depend are crushed, and the roots are essentially
left gasping for air. Without oxygen, the grass plants become weaker and will
eventually wither and die.
Aerification is a mechanical process that creates more air
space in the soil and promotes deeper rooting, thus helping the grass plants
stay healthy. In most cases, it’s done by removing ½-inch cores from the
compacted soil, allowing for an infusion of air and water that brings a
resurgence of growth. The spaces are then filled with sand “topdressing” that
helps the soil retain air space and makes it easier for roots to grow downward.
Older greens often are constructed of soils with significant
amounts of silt, clay and fine organic particles that are prone to compaction.
Filling aerification holes with sand improves drainage and resists compaction.
The periodic introduction of sand to a green’s top layer can over time, avoid
or postpone expensive rebuilding or renovation of greens.
Finally, growing of turf adds to a layer of organic matter
on the surface. This layer, called thatch, is an accumulation of dead stems,
leaves and roots. A little organic matter makes for a resilient green, but too
much invites diseases and insects. Topdressing with sand can prevent thatch
buildup, and aerification is one of the best ways to reduce an existing layer
and prevent an excess of thatch from becoming established.
Other aerification techniques use machines with “tines” or
knives that simply poke holes through the soil profile. A new technique even
uses ultra-high-pressure water that’s injected through the soil profile to
create small holes that relieve some compaction but heal quickly.
There are many types of aerifying machines with different
attachments that address different problems in the various stages of the life
of a green. So, the next time you’re ready to scream when the aerifiers are
brought on the course, remember that a little preventative maintenance produces
the best greens over the long haul.
The bottom line is that aerification is a necessary
practice. At Highlands CC, a majority of our heavy aeration is done during the
off season. However, we will
periodically “vent” the greens using ¼” hollow tines during the season. This ensures your greens will continue to
drain well and last the whole season.