Since soil creatures definitely have a positive impact on soil quality, no-tillers normally do all they can to manage their soils in ways to protect and nurture these valuable creatures.

A new study at the University of Illinois that focuses on how soil invertebrates can have a positive impact on the soil system should be of special interest to no-tillers. Ed Zaborski, a soil invertebrate ecologist with the Illinois National History Survey, believes that no-tillers should manage their land to produce the best possible soil-building benefits provided by these creatures.

Soil Condition Indicators

His study is looking at earthworms and mites as possible indicators of soil condition and their response to insect control strategies.

This is being done by bagging and burying crop residues in plots where three corn hybrids — each with a Bt line and a non-Bt line — are grown. After half the plots are treated with insecticides, a few bags are collected every few weeks and the invertebrates extracted and counted.

“We can determine the impact of insecticides, the growing crop and the quality of the residues,” he says. “After analyzing the residues, we’ll know the rate of decomposition for several points in time. So, we can look at the effect of insect control strategies on the soil process and the decomposition of residues.”

No Earthworm Concerns

Zaborski hasn’t found any negative impact to earthworms due to Bt endotoxins. “With the three lines of corn used in our study, it looks like the impact of genetically…