Integrative Perennial Cropping Systems to Produce Food, Bioenergy, and Ecosystem Services.

A major challenge for agriculture in the 21^stcentury is to develop diversified farming systems that optimize the production of food, bioenergy, and ecosystem services. The diversity and productivity of many products (i.e. fiber, bioproducts, and fuel) and ecosystem services could be enhanced by the establishment of perennial crops on agricultural landscapes. Our research focuses on the integration of perennial crop configurations (prairie, willow, and prairie-willow alley crops) in soybeans. We are 1) quantifying the production of bioenergy from these cropping systems and 2) evaluating the effect of perennial crops on insect predators and biological control of the soybean aphid.

The prairie polyculture species mixture was designed to provision ample floral resources to insect predators while providing biomass bioenergy. Throughout the growing season, the prairie produced a total of 13 native flowers per m² and 0.3-0.5 kg dry biomass per m² (1.3-2.2 tons/acre). There was a greater abundance of insect predators (e.g. lady beetles, lacewings) in soybeans grown adjacent to willow and prairie; the increase in insect predators was associated with greater suppression of soybean aphid population growth in 2012 but not 2013. Short-rotation willow produced more biomass and theoretical ethanol yield than prairie polyculture. This research will provide insight on strategies to incorporate perennial crops in ways that support and enhance conventional production systems, provide new sources of perennial bioenergy and increase biological control of insect pests.