The beneficial effects of earthworms on soil structure, chemistry, microbiology, and crop yield are well demonstrated. Advanced Prairie, Inc. has developed a method of harvesting and encapsulating earthworm cocoons to make them available for mass market distribution. A previous study demonstrated the storage and shipping viability of the encapsulated cocoons. Now we need to determine earthworm hatch and propagation rates in actual field conditions. PURPOSE: (1) To determine the hatch rate of hand-inoculated earthworm cocoons in actual soil environments. (2) To identify those factors that have the greatest impact on earthworm populations. (3) To observe and document earthworm propagation rates. OBJECTIVES: Objective (1): Assess hatching success of encapsulated and unencapsulated cocoons of Lumbricus rubellus and Dendrobaena veneta under normal field environmental conditions. Objective (2): Determine the effects of moisture and available organic matter on the hatching and hatchling spread of encapsulated and unencapsulated cocoons of Lumbricus rubellus and Dendrobaena veneta. Objective (3): Initiate a larger-scale field experiment to provide baseline data on the longer-term success of in-field earthworm cocoon inoculations, to fully populate whole fields (Phase II research). APPROACH: The Phase I effort consists of three experiments: (1) The Outdoor Hatch Rate Experiment will assess cocoon hatch rates in natural field conditions. We will place earthworm cocoons into a removable double-mesh container, which we will then place in an operating farm field and remove for inspection periodically during the growing season to determine hatch rates. We expect to observe a hatch rate of more than 50% from the mesh cage observations. (2) The Indoor Hatch Rate Experiment consists of a large number of plastic bins containing the soil from the outdoor plots, but placed indoors under controlled conditions. Each bin receives a specific moisture treatment (high or low), organic matter addition (3% or 10%), earthworm species (Lumbricus rubellus or Dendrobaena veneta), and cocoon encapsulation (yes or no). The controlled conditions will allow us to assess not only earthworm counts but size and maturity as well. We expect to observe a hatch rate of more than 60% for optimal treatments in these controlled conditions. (3) The Outdoor Population-Growth-Over-Time Experiment will provide baseline data regarding long-term earthworm population development in the soil. Results of this experiment will have only limited import in the 8 months of Phase I, but will yield much more significant results if continued into Phase II research as planned
