Introduction

This test was performed to investigate whether SoilTech can support the claim "loosens and aerates compacted soils." Two tests were selected to determine if SoilTech can support the claim. High soil bulk density and high soil strength are both a result of compaction, and both reduce infiltration and percolation, which increases runoff and soil erosion.

Question

Can SoilTech reduce both soil bulk density and soil strength, thereby reducing compaction?

Test Site

The Arrowhead Sports Complex is recognized nationally as one of the best in fast pitch softball, except for a drainage problem. It was chosen because the Turf Manager, Jim Hillman, had had recurrent standing water problems for the last several years, following ordinary rainfall. Game cancellations were common because the infields were draining slowly, thereby prolonging the drainage and drying process. It had been recommended to Jim Hillman that the way to solve the drainage problem was to construct a "French drain" system for all 8 fields. The cost estimate for this project was $4200, for each field.

Control

All 8 infields were treated equally with SoilTech. Test measurements were recorded on Field 1, Field 2 and Field 4 which were the fields with the most severe drainage problems.

Application The first application was on May 22, 2001. Dilution rate was 2 oz. SoilTech per 1 gallon water. Coverage rate was 4 oz. SoilTech per 1000 square feet. All areas treated were irrigated with 1/4" of water. The second SoilTech application was on June 1, 2001. Application rate, coverage rate, and irrigation were identical to the first application.

Tests Performed

Bulk density - Soil bulk density is the weight of solid material in a given volume of soil. For laboratory analysis, core samples were taken with a 0.7" diameter sampler to a depth of 8 inches. The sample was dried to remove water and then weighed. Bulk density is calculated by dividing the dry weight of a sample by its volume. What one is looking for in this test is to have a low bulk density, because if the soil is less dense then it will have more room for water, air, and nutrients to move around.

Soil strength - Soil strength is a measure of the penetration resistance of a soil. A handheld recording cone penetrometer (Rimik-Agridry CP20) with a 0.047" diameter cone was used to measure soil strength. The cone penetrometer measures the load required to push the cone down into the soil, recording the penetration resistance of the soil. This penetration resistance is a measure of soil strength and is a measure of the resistance to penetration by root tip elongation (how hard it is for turf roots to grow down into it.)

Interpretation

Bulk Density - The significant reduction in soil bulk density for all three fields means that an increase in soil pore space will allow for greater infiltration and percolation. Individual particle size increased, thereby creating more porosity in the soil.

Soil Strength - The reduction in soil strength for all three fields indicates reduced soil compaction.

Results

Jim Hillman (Turf Manager of Arrowhead Softball Sports Complex) noted a remarkable increase in drainage from all the fields. To date, there has been no rain cancellation after application of SoilTech. Several rain events have occurred since application, and in every case the fields drained within a few hours. Field 4 in particular was troublesome before the application--standing water developed between first and second base after a significant rainfall. Before SoilTech application, water would stand in this area up to 3 days. Field 1 between second base and third base was another trouble area. Field 2 in front of second base had persistent standing water problems after significant rainfall. Since the application of SoilTech, no standing water problems beyond the first day have occurred. In some cases, significant drainage occurred within one to three hours and play that was impossible before SoilTech resumed.

Mowing frequency increased to every 2 days and the blade height was adjusted to cut 1/2" taller, to keep mowing times to 18 minutes per field.

Irrigation was reduced from 20 minutes 3 times per week to 20 minutes 1 time per week even when daytime temperatures were averaging at or near 100 degrees in July and August.

Conclusion

SoilTech has reduced soil bulk density and reduced soil strength enough to make a remarkable difference in infiltration and percolation. The test supports the product claim that SoilTech "loosens and aerates compacted soils."