Soils and Water: Soil Profile

The second post in this series will give a very brief overview of what soils are made of and how those parts interact with water.  We can build from this in the future posts that will be more specific about each area of the golf course.  The preferred soil for providing a high quality playing surface has a large amount of air space for roots and water to move through the soil.

Soil consists of sand, silt and clay particles along with an organic component.  The fractions of sand, silt and clay in a soil determine its suitability for providing a high quality playing surface.  This figure on the right is one of the first diagrams that is learned in a soils class.  When the fractions of each soil particle in a given soil have been identified, you can use this diagram to classify the soil.

Sand particles are larger than silt particles which are larger than clay particles.  The larger the particle, the more air space between the particles.  If you have a bowl in your kitchen and fill it with oranges, there will be large empty spaces in the bowl between the oranges.  If you fill that bowl with grapes, the empty spaces between the grapes will be much smaller compared to those that the oranges create.  The larger the particle, the larger the air space between the particles.  It is much easier for water and roots to move through a larger air space in the soil.  So, there is a larger air space between sand particles than there is air space between silt particles, which has a larger air space than between clay particles.  This is why soils that are higher in clay are much slower to drain.

The other component of the soil that was mentioned earlier is organic matter.  In the turfgrass soil, this organic matter comes from dead tissue from the grass plant (because there are no trees nearby, right).  This organic matter has a high capacity to hold water.  As a result, water is slow to move through organic matter because of its ability to hold the water as it attempts to pass.

It is not accident that this string of posts comes in conjunction with the beginning of our aeration this fall.  The following posts will be more detailed about the specific areas of the course, and why we do the maintenance practices that we do.