With the goal of evaluating the use of cover crops to help corn and soybean farmers during the transition to certified organic production, we are quantifying the ecosystem services from cover crops in organic cropping systems. Farmers growing corn during the transition period face major challenges with weed suppression and soil fertility, and many farmers do not have the necessary equipment for planting forage crops or small grains and these alternative crops are not as profitable as corn and soybean.
In what ways will incorporating cover crops into a corn and soybean rotation improve ecosystem services (e.g., improved soil health and invertebrate weed seed predation)? Does utilizing a cereal rye cover crop increase profitability of the system?
One of our experiments at the Musgrave research farm compares different tillage systems utilizing cover crops to grow silage corn and soybeans. The goal is to examine the impact of different cover crop management practices on soil health indicators and corn and soybean yield. The treatments are: 1) Roller-crimping: cereal rye cover crop left as surface mulch, 2) Double cropping: cereal rye cover crop harvested in the spring for baylage, 3) Plow down: cereal rye biomass incorporated into the soil, 4) Control: no cover crops planted. Soybeans were planted in 2015, corn silage will be planted in 2016, and soybeans again in 2017. Hairy vetch is interseeded into the soybean at the third trifoliate stage, to provide a legume cover crop before the next season’s silage corn production.
The second experiment explores the relationship between cash crop plant density, light transmittance, cover crop biomass, and weed seed predators.The goal is to evaluate the effects of interseeded cover crops on the performance of corn and soybean and ecosystem services. A cereal rye-ryegrass-legume cover crop mixture was interseeded in between the corn and soybean rows in mid-summer. We measured light transmittance through the cash crop canopy and assessed weed seed predation by setting out seed arenas for invertebrate and vertebrates.