Evaluation of Integrated Diverse Dairy Cropping Systems Designed for Sustainability & Ecosystem Services.

Dairy farms in the Northeast often produce the forage crops for the dairy herd on-farm, but import most of the feed grain crops. We are evaluating integrating the dairy forage and grain crop production for a typical-sized Pennsylvania dairy farm (65 milking cows, 97 hectares) with two 6-year crop rotations. The rotations were designed to integrate no-till, legumes, cover crops, crop diversity, and integrated pest management to promote ecosystems services, such as soil and nutrient conservation, pest suppression, and economic and energetic input savings. Within each rotation we are evaluating: i) shallow-disk manure injection for nutrient conservation and green manure crops, or ii) a combination of strategies to reduce herbicide and insecticide use. We initiated the study in 2010 at 1/20^th the scale (5.67 hectares) in a full crop entry experiment with four replications. A corn (Zea mays L.)-soybean (Glycine max L.) rotation with pre-emptive pest management practices was also included for comparison. We are quantifying multiple indicators of system performance such as crop yields and quality; soil fertility and health indicators; weed and pest populations; and nitrogen losses. We are simulating dairy herd production with a dairy nutrition model, and using computer estimation tools to estimate cropping system energy efficiency. Over six years, we have altered the cropping systems to sustain the dairy herd forage production in dry years, address nutritional needs of all livestock groups, and reduce crop damage due to slugs (Arion sp.). Shallow-disk manure injection and legumes have reduced off-farm N inputs; and integrated weed management has reduced herbicide use and provided sufficient weed control. The ecological, conservation cropping systems have also provided insect pest management and soil health benefits, and produced the majority of the dairy feed with energy savings.