Why Expanded Shale is an Excellent Choice for Engineered Soils

There are 2 major types of conditioner/topdressing for baseball and softball infields.

1. Calcined Clay (Turface, Pro’s Choice Soilmaster, Diamond Pro Professional Calcined Clay, etc) 
2. Expanded Shale (Diamond Pro Red Infield Conditioner)

What is Calcined Clay?

First, let’s look at calcined clay.  Calcined clay in a montmorillonite clay fired at 1500 degrees in a rotary kiln.  So, in the most basic terms, the clay is turned into a ceramic (think pottery in art class)  Once the clay is a porous ceramic it becomes very absorbent. That is why this material is great for drying a wet infield.  

What is a Drying Agent?

Many drying agents also exist. (Rapid Dry, Quick Dry, Calcined Clay Drying Agent)  Simply, they are the finest particles of calcined clay.  Why do they absorb moisture better than a coarser grade particle?  The smaller particles cover a greater surface area, thus a quicker “drying” material.

A couple common misconceptions with calcined clay:

1. I can till calcined clay into my infield to raise clay content - FALSE.  As explained above, once fired, montmorillonite clay is no longer a clay.  When calcined clay is tilled into an infield profile, the infield mix will become looser and can assist in holding more moisture in the column. Keep in mind, tilling in too much calcined clay is similar to adding too much sand - the column will become too loose for play.
2. I have to add a drying agent to dry a puddle - FALSE.  Any calcined clay will absorb water.  Keep in mind, the finer the particle the quicker the absorption of water.  RECOMMENDATION - Stock only professional grade calcined clay.  This product will work day in an day out as a topdressing.  If additional material is needed to dry a wet infield, the additional product will not only absorb water but also remain as a long term topdressing. 

What is a Vitrified Clay/ Expanded Shale?

Simply stated, a vitrified clay/expanded shale is fired at over 2000 degrees.  The product produced is lightweight and extremely durable.  This product WILL NOT absorb as much moisture are calcined clay.  During rain events this material will shed water to the base material to rehydrate the column while also ensuring the water runs off the infield.

Why is Vitrified Clay/Expanded Shale a Good Choice for Engineered Soils?

Engineered soils are materials that are blended via computer to ensure that the infield mix is consistent time after time.  Due to this fact, engineered soils are the best product for value for infield mixes.  Engineered soils can take large rain events and stay firm under foot.  Furthermore, engineered soils will not become dusty when dry.  Due to the above facts, vitrified clay/expanded shale is a great choice for a couple reasons:

1. The expanded shale allows for moisture to be shed to the engineered soil to more quickly drain the rain event while also allowing moisture to re-hydrate the base material.  This is a great benefit for recreational surfaces that only see moisture during rain events.
2. The weight of expanded shale (heavier than calcined clay) will allow the material to stay in place and lessen the chances of the topdressing “blowing around” the infield.
3. Bulk Materials - expanded shale is produced and available in bulk at a reduced cost.  Oftentimes the cost of bulk material is 1/2 the cost of bagged products.

In conclusion, calcined clay is a necessary product to have in stock to address wet areas of an infield after a rain event.  Expanded shale is a extremely durable product that should be considered as the base topdressing/sliding surface on an infield.  

Click HERE to learn how to dry an infield after a rain event.

Go to j-dturf.com to learn more about J&D Turf.

Play on!

--Jamie