Arthropods in Organic Reduced Tillage Systems.

Biodiversity tends to be higher in organic cropping systems in comparison to non-organic systems, and this is true for arthropod diversity. Both pest and beneficial arthropods can contribute to this increased diversity. In organic agronomic cropping systems, growers primarily rely on cultural practices and natural enemies to manage arthropod pests, and it is critical to build and conserve natural enemy communities to help prevent pest outbreaks.  The effects of specific management decisions made during and post-transition to organic production can affect arthropod communities and the risk for crop losses from arthropods.  Typically, organic crop producers rely on tillage to control weeds and incorporate animal and green manures.  However, frequent or intensive tillage can result in an overall decrease in soil quality and reduce the functional capacity of a soil. Soil faunal biomass often drops with use of inversion tillage, and intensive or frequent tillage can suppress beneficial soil organisms, including arthropods.  To reduce the negative effects and costs associated with intensive tillage in organic systems, researchers and organic farmers are experimenting with practices and rotations to reduce tillage.  In this presentation, we will review what we and others have learned about the impacts of reducing tillage on arthropods and biological control in organic agronomic cropping systems.