Written by Dan Jennings
I am extremely fortunate in my career to learn/work firsthand with an industry leading company like DuraEdge, DuraEdge has cleared the path for engineered infield mix soils. I have also seen and implemented these same ideas as a professional groundskeeper over the last decade. This is a question that comes up daily in my current roll, what is an engineered soil.
What is the definition of engineered soil, it is a soil that has been manufactured or blended with soil components of sand, silt, clay, and other organic matter components to meet a specific gradation. The definition of the word structure, a structure is something that is built from several components that are put together, many people know structures as skyscrapers, houses, bridges and so on. These definitions will help as we dive into the importance of infield mix soil structures in this blog. Native soil or geological formation structures consist of a wide variety of soil components. These components can change depending on what part of the country your sampling material. Understanding and mechanically blending these soil components are a crucial step when building a structure that will become stable. Mechanically blending soil components is already completed every day when producing concrete for bridges, and the asphalt we drive on. The reason for mechanically blending these types of materials are due to the ability to build consistency and predictability when installing or managing the curing process. These added costs upfront for blending these soil components are to build consistency, which is a crucial step for managing future cost or ROI (Return on Investment). If we did not have these engineering practices in-place we could never answer the question of when a bridge may fail, or when to forecast the allocated funds prior to failure. Standard cost analysis is done prior to repaving highways or building structures.
As a green industry, we’ve seen this same exact change back in the 1960’s when golf courses transformed from a native push-up green to the USGA specified engineered soil rootzone. To make a USGA engineered soil rootzone you must blend and screen several size sand particles to meet a specific gradation. This specific gradation will give the soil structure and consistency, we see this consistency with ball roll on putting greens. This process back in the 1960’s and to-date brought consistency to rootzones. The USGA rootzone specification allows Sports Turf Managers to manage moisture evaporation and brought uniformity when overseeing nutrient loss or inputs. Having the ability to manage moisture evaporation, has now given our industry the capabilities to manage irrigation inputs to help provide a safe and healthy playing surface for our teams.
Now let us dive into the fun stuff, infield mix soil structure components and why they are important. An engineered infield mix soil structure is built to preform based on each specific maintenance input ability. Production plants have the capabilities of adjusting sand and clay levels in the infield mix soil. Higher clay content will lead to higher levels of maintenance requirements. Sand particle sizes will range from very coarse, course, medium, fine, and exceptionally fine, each one of these particle sizes will play an extremely important roll. These sand particles will be the building blocks, besides setting the structure, they will also give this structure void spaces for silt and clay particles. Silt particles fall into two size columns, course and fine, these particles will allow proper bridging between large particle sands and extremely small particles like clay. These silt particles will ensure no interfacing or chipping when the structure has been built. Clay particles are small, clay is 2 to infinity and measured in microns, coarse sand is 1000 micron and the silt has a range of 50-2 micron. One micron is the width of a piece of hair on your head. Clay particles are small but make an enormous difference on the playability of the infield soil structure. Clay expands when it is hydrated and becomes sticky, clay acts like a mortar that holds the structure together. This mortar cannot work without moisture, moisture is the glue that gives these structures integrity and elasticity. Managing the moisture in an infield mix soils properly gives the ball consistent hops off the ground and a cushion for players to play on. This cushion effect is called the cork board effect, this cork board effect has been seen on DuraEdge’s infield mix soils for the last 15 years. This type of cushion or corkboard effect would not happen without specific clay mineralogy and proper hydration. This corkboard effect is also known as cleat in and cleat out of an infield mix soil when it is hydrated properly.
I have studied soil test, held, and managed clay formations around the country and each clay mineralogy is vastly different. Let us jump back to the geology class, when the ice formations pushed glaciers down from the northern part of the earth, it rolled, crushed, and pushed our earth's crust layer. This erosion process completely broke down and changed every soil particle in its wake. Geological data has shown where rivers have run from what we call California today, that connected all the way to the Great Lakes, some of these areas are now deserts. The earth’s crust formation changes have profoundly affected every particle, we sometimes forget that rain and water currents have massive impacts on the degradation of soil particles as well. Understanding each particle and how it reacts in soil structures is what engineers’ study and provide reports on every day. Since clay particles range in sizes, each engineered soil structure will play differently. Southern and western clay formations are significantly smaller particle sizes than other formations found in the United States. This is simply the process of understanding clay formation structures and the appreciation of soil geology. Each clay particle will react with moisture differently, geologist evaluating these types of particles every day to continue the understanding and measurability of each particle.
So why is all this information so important? As our industry evolves with technology and understanding, there are new ways to manage cost and show true return on your investment. Most of the issues we battled 20,30 or 40 years ago have evolved to make life easier, this tools and understanding have helped keep labor and material cost down. As we know, budgets continue to rise at a minimum rate but using modern technologies upfront can help divert cost from one area to another as you implement these evolutions into your facility. These modern technologies will also build consistency throughout your facility and allow you to consistently forecast inputs like product materials and labor constantly, depending on weather events.
Stay safe and never hesitate to call/text/email, no question is ever dumb, the only dumb part is not asking.
I really want to thank you for taking the time to read this blog, truly means a lot and I hope this makes your groundskeeping life easier. Feel free to email/text any questions if you would like further insight.
For now,
Dan Jennings
#inspiredbysoils