For years, building and maintaining baseball/softball infields was considered an art. What one groundskeeper thought was a great infield, another thought it was a poor infield.
The process was subjective and creative. How many times have you heard, “I’m looking for some black dirt.” Or, “I’m looking for some red clay.” Times are changing and the tide is turning to science. Why?
Simply stated, when the process is a science, soils are tested and results can be predictable, and replicable.
Three components of good infield mix:
- The deepest part of the profile is a compacted native soil sub base that is 3-6 inches below the surface.
- The infield mix exists. The mix is the “meat” of the infield. The material is usually engineered, imported, compacted firmly, and has surface drainage.
- 3.1/8-1/4 inch of topdressing rests on the surface much like mulch.
Sand, the largest soil particle, provides the structural integrity of the infield. The targeted range is 58-75% and over 50% of the sand should be retained on the medium sieve.
Silt, the second largest soil particle, acts as a bridge between the sand and the clay. 10-35% is the acceptable range.
Clay, the smallest soil particle, provides the color of the mix and retains moisture. 15-35% is the acceptable range.
The take home message on silt/clay is that the ratio of silt/clay should NEVER be higher than 1:1.
So, what makes a good mix? Three important factors: traction, playability, and consistency.
A mix should provide consistent traction, the ability for athletes to play the game without sliding/slipping around the infield. The infield should play consistently in a variety of weather conditions.
How many time have you heard, “I hope it doesn’t rain, we will be shut down for 3 days!”
When all the characteristics are achieved, the infield is considered a “balanced soil.”