Effects of cover crops and soil health practices on insect community dynamics in a corn production system

Today, many agricultural landscapes aim to maximize the amount of harvestable land, which has resulted in a reduction of agroecosystem biodiversity. Our study investigates the effects of cover crop diversity, insecticide use, and soil conservation practices on the abundance and diversity of insect and arthropod communities, and subsequently, the effects that these communities have on several soil properties which indicate soil health. The objective of the study is to implement vegetation diversity and soil management to increase arthropod biodiversity, as well as to quantify the effects that arthropods have on soil health. The hypothesis addressed in this study was that insecticide use and cover crop utilization affect pest abundance and predator: prey ratios in corn fields. The role of cover crops in reducing insect pests of corn, increasing natural enemies of pests, and encouraging insect contributions to soil health were investigated in eight paired treatments conducted across four states (NE, SD, MN, ND). Insect diversity and soil properties were tested in plots that had either no cover crop established or had a diverse cover crop established, in addition to no-till practices in some fields. Data were collected within systems that were defined and created by the producers, to emulate a realistic crop producing scenario to examine this systems-level question. Soil qualities were assessed by taking soil cores for analyzing Soil Organic Matter (SOM), testing water infiltration rate and determining soil bulk density. Insect communities in each field were assessed by taking soil cores, quadrat suction sampling, and by counting all insects on whole corn plants.  Preliminary data reveal that fields that had cover crops and used soil conservation practices had fewer pests, and a higher predator: pest ratio than fields that lacked cover crops.