5 Top Reasons We Aerify
1. Control thatch
2. Ability to provide increased firmness and corresponding green speeds
3. Extract excessive organic matter accumulation
4. Improve Soil Gas Exchange
5. Allow the plant the ability to maintain an effective root system throughout the growing season
Aerification is an important
cultural practice. If you read the newsletter you will see we discuss this
topic several times each year. Through
aerification we; 1) extract excessive accumulation of organic material; 2)
improve soil gas exchange; 3) stimulate new root development; 4) stimulate
microbial activity; and 5) improve the plants ability to withstand biotic and
abiotic stresses.
Greens Aerification |
Having said that, there are still
plenty of golfer skeptics! Aerification is one of the most despised cultural
practices when it comes to the golfer as it disrupts the playing surface; is
usually done during the prime playing seasons; and according to most golfers
has no redeeming features other than to decrease green performance and raise
one's golf score. On the other hand, aerification is likely the most important
cultural practice that a turf manager can perform. Why? Simply put to maintain
a root system under the target plant. The plant's response is to maintain
density enabling it to tolerate traffic, and resist ball marking; maintain a
deep effective root system to withstand limitations on water quantity and water
quality; maintain healthy plant growth to tolerate biotic and abiotic
stresses.
Aerification Plugs |
Aerification is an active process of
removing excessive organic matter (OM) in the upper root zone. As plants grow;
roots, stolons and rhizomes will develop increasing the level of organic
material in the upper soil profile. The more plant growth, the healthier the
plant in providing a superior playing surface. The down side is organic
accumulation. Left unchecked, the level of Organic Matter can actually create a
high OM layer which by itself can change the dynamics of the root zone.
Periodic monitoring of the root zone is proactive in maintaining a uniform
balance in the amount of OM, Sand, Silt and Clay throughout the soil profile.
If an organic layer accumulates near the surface it can restrict water and air
flow into the root zone. During periods of high abiotic stress (heat stress)
the plant demands much more plant available moisture and soil oxygen. Restrict
either and the root will also be restricted.
Greens Topdressing |
OM will seal the soil surface from
water and air infiltration; accumulate salts from Evapotranspiration (combined
loss of water through evaporation & transpiration) and effectively cause
suffocation of the root zone. Ever wonder why roots are shorter in the heat of
the summer, in short they suffocate. The OM restricts the availability of soil
oxygen, which under high soil and air temperatures is quickly depleted due to a
rapid level of root respiration. A simple resolve to this problem is to
recognize that aerification is not an annual event; it is an event that should
occur frequently and with a purpose. Aeration does not have to always include
extracting cores, it can also be accomplished by using solid tines [VENTING] to
continually create vertical shafts of air space deep into the root zone
profile. These VENT shafts are in reality MACROPORES, the site of gas exchange,
excessive moisture evaporation, and points of moisture and soil gas
infiltration.
Fairway Aerification |
Root growth and maintenance requires
frankly a lot of soil oxygen, one of the best ways to deliver is to aerify and
especially during the periods of high demand. Aerification for the purpose of
OM extraction should be done during the period of time the plant is most
active. This assures that the physical hole created by removing OM will heal
rapidly. The USGA in their wisdom has suggested that 20% of the upper root zone
cavity should be extracted on an annual basis.
Aerification during the most active
growth period of the year will aid in extracting OM. The timing is really
species dependent (Bermudagrasses and Zoysiagrasses have the most active period
during the summer, whereas the Bentgrasses are the most active in the early
spring or late fall). Periodic monitoring of the organic layer will aid in
determining how frequently core aeration is required. Maintaining an OM layer
of 3/8” –1/2" in depth or 3-4% volume by weight is acceptable and will
provide good plant response, excess of that can cause problems during the heat
of the summer.
Solid Tine versus Coring Tine |
VENTING the greens through the
summer months to generate and maintain active macropores is most important and
must be done frequently. Along with providing excellent moisture and gas
exchange, the improvement in soil gas exchange also supports and stimulates
microbial activity and therefore enhances the rate of OM decomposition.
Combined with light frequent top dressing (dilution of OM), the core removal
(extraction), and the microbial activity (decomposition), the root zone will be
supportive of a deeper more effective root and healthier Turfgrass plant.