Key #1: Aggressive Cultivation

3 Keys to High Quality, High Traffic Grass Fields 

(Note:  3 Keys To High Quality, High Traffic Natural Grass fields is copyright of the Natural Grass Advisory Group and Growing Innovations).  

Key #1:  Aggressive Cultivation 

Concentrated foot traffic can quickly compact soil on grass fields. Compaction eliminates air space and leads to suffocating roots. The gasping roots weaken and the sword of grass to begins to thin out. Thinning, along with a sod or organic layer compound compaction leading to divots and blowouts.   Weak roots require additional hydration, yet water from irrigation and rainfall is not able to penetrate the compacted soils easily. A compacted field surface is a Sports Field Managers nightmare!

Cultivation solves the problems caused by compaction and yields increased turfgrass density and decreased water usage. Because water is better able to move through the soil profile, it also decreases the number of events cancelled due to rainfall.

However, on a high traffic field, the traditional “basic” approach to cultivation of a few times a year is NOT enough. A field under continual foot traffic requires continual aggressiveness with cultivation.

Yes, historically it has been taught that cultivation only needs to take place these few times a year.  And many times cultivation is avoided in a fear of actually causing more damage to a field. Especially during times that the field in experiencing heavy use. However we know the damage that compaction and surface hardness can cause.  Now GMax, compaction testing, and infiltration rate data all paints the picture for us even more clearly.

Limited, conservative cultivation has lead to the current public perception that natural grass surfaces can NOT sustain heavy use, need long periods of rest, and are rained out easily.  AvoidIng the fear to be aggressive while using good judgement on how and when now has evidence on counteracting those compaction issues and actually increase use on a grass field.

“Inaction may be safe, but it builds nothing.” Dave Freudenthal.  And if “you always do what you have always done, you will always get what you have always gotten.” Albert Einstein

Compacted soil on sideline of field showing last cultivation practice defines the word “aggressive” as “vigorously energetic, especially in the use of initiative and forcefulness”. This definition is an excellent outline to use in your decision making towards cultivation. A cultivation program should be “vigorously energetic”: implemented a minimum of 2-4 times per month. It should show “initiative and forcefulness”: taking place in short windows of opportunity between events and in conditions that may not typically be seen as ideal. This could mean cultivating cool season in the heat or working all night right after an event in order to utilize a short break completely. Finding time when it seems that there is no time.

FC Dallas Stadium, a high traffic soccer and football field (2011 STMA Professional Soccer FOY) sets the standard for what it means to be “aggressive”. Sports Field Manager Allen Reed aerates his field every Monday.  See More Here In a Feature He Shared With Us:  How Our Grass Field Takes More!

Elsewhere, Ryan Bjorn at Maryland SoccerPlex has a minimum of 1 operator continually  cultivating the 19 natural grass fields he oversees.  The non-stop process equates to a 7-10 day cycle between cultivation on fields that host over 350 events apiece each year from soccer, lacrosse, and sports camps. SoccerPlex Stadium was 2014 STMA Professional Soccer Field of the Year, making it one of the most high traffic fields to ever win the professional award.  Read More Here:  Turning Green Into Gold, Maryland SoccerPlex 

At Sporting Kansas City’s Swope Park Training Center fields, placed under high demands as well, Justin Bland never allows the fields to pass a cultivation window of 14 days.  With this approach, Sporting (then the Wizards) won STMA Professional Soccer Field of the Year in 2010 on the stadium field hosting both professional baseball AND professional soccer.  Read More Here:  Wizards Grounds Crew Earns FOY

Nationals Park in Washington, DC hosts Major League Baseball, concerts, and a variety of cooperate and community events.  John Turnour utilizes a form of cultivation between every single home stand.  He even sometimes doubles up on his cultivation practices and averages nearly 3x per month.

This aggressive cultivation keeps grass fields from experiencing turfgrass decline due to compaction. It also keeps water moving vertically through the field’s soil profile, increasing irrigation efficiency and reducing rainouts.

There are many forms and options for cultivation practices.  Here is an introduction to a few of those:

De-compaction Aeration
De-compaction aeration is one of the basic and accepted forms of cultivation. De-compaction aeration breaks up compaction deep in the soil, 8 to 10” deep. De-compaction aeration promotes water movement through the soil profile and allows roots to grow deep and strong. Two examples of de-compaction aeration are:

Soil Wave

Soil wave de-compaction following Universe fraze mow on bermudgrass

Soil wave de-compaction following Universe fraze mow on bermudagrass

Deep tine

Deep tine aeration

Deep tine aeration

Deep tine and core aeration in conjunction w/ one another on heavy compacted clay

Deep tine and core aeration in conjunction w/ one another on heavy compacted clay

Surface Aeration
Surface aeration another basic and accepted form of cultivation. Rapid tine aeration machines can make shallow tightly spaced holes to open the surface and allow air into the soil. Needle tines, knife tines, cross tines, etc all offer different options. Coring tines not only open the surface, they remove organic build up and reduce layering from sod. Slicing and spiking also open the surface as well.

Surface aeration via core aeration w/ rapid tine aerators

Rapid tine aeration w solid tines to vent surface following heavy play

Rapid tine aeration w solid tines to vent surface following heavy play

Aerway Surface Slicer

Aerway Surface Slicer

Recycle Dressing
Recycle dressing comes from a machine invented my Mr. Ko Rodenberg, former Superintendent of Park Maintenance in Rotterdam, Holland. All in one pass, the machine is able to accomplish both de-compaction and surface aeration. The recycler de-compacts the sub soil by removing soil with cutting blades. The surface soil is then opened up with slicing blades. Finally the machine “recycles” the removed material over the top of the surface as topdressing to be dragged back in.

Recycler dressing to de-compact and open the surface

Recycle dressing lines following dragging in sand

Recycle dressing lines from small blades on ryegrass following dragging in sand

Recycling dresser lines from big blades on Latitude bermudagrass following dragging

Recycling dresser lines from big blades on Latitude bermudagrass following dragging in sand

 Air Injection Aeration
Another unique and new form of aeration comes from air injection. Air injection machines force high-pressure air into the soil profile much like the former Toro hydroject force high- pressure water into the soil. The force of the air fractures even the hardest of soils to promote de-compaction and to re-introduce air into the profile.

Air Injection Machine

Brushing is a very simple practice, but the results can pay dividends. Brushing stands up the grass and fluffs a good amount of thatch to the top of the canopy. Blowing, sweeping, and/ or catching clippings will help when there is a large amount of material brought up.

Brushing to bring up thatch

Verticutting is another basic and accepted from of cultivation for the attempted control of thatch and organic build up. Verticutting also promotes density and durability. Standard verticutting removes around 11% of the material, so use this practice as much as possible. Especially on actively growing bermudagrass.

Verticutting Kentucky bluegrass

Universe Fraze Mowing
With the statistic of standard verticutting removing approximately 11% of the surface material, Universe fraze mowing has been introduced in order to remove 100% of the desired depth of thatch and organic build up. Universe mowing also removes weak poa annua plants, poa annua seed, and other weed seed as well. The regeneration from Universe mowing promotes density and durability, eliminates surface slickness, and creates a smooth playing surface as well.

Universe fraze mowing bermudagrass

Universe fraze mowing Poa Annua out of Kentucky bluegrass

These practices, along with others, provide grass field managers with a wide range of cultivation techniques to implement as often as possible. Start small and expand.  1x every 2 months to 1x every 1 month is a 100% increase.  This is great!  If your salary was increased 100% today, think how happy you would be.  Same goes for the grass plants.

Yes, many times cultivation is avoided in a fear of causing more damage to a field.   Especially during times that the field in experiencing heavy use. However we know the damage that compaction and surface hardness can cause too.  AvoidIng the fear to be aggressive while using good judgement on how and when can counteract those compaction issues and increase use on a grass field.

Inaction may be safe, but it builds nothing.Dave Freudenthal.

Think different and take action. Grass fields can take more!

HGT Kentucky bluegrass under aggressive cultivation following 167 events in less than 6 months.

2 thoughts on “Key #1: Aggressive Cultivation

  1. This article is awesome! Very well done! These practices lead to sustainable management of athletic fields. The more the traffic the more the cultivation! Mow, Cultivation, Fertilization, Weed Control and Topdressing in that priority order! Mow, Cultivate, Irrigate, Repeat! Thanks for the photos along with the caption as well as the definitions of the phrases and unique methods. Diversity in technique compliments frequency. I also enjoyed the quote “Inaction may be safe but it builds nothing!”

  2. Pingback: Key #2: Traffic Management; Three Keys of High Traffic Grass Fields | Growing Green Grass

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