plots in this study will show what's already been demonstrated in other studies — that corn yields are significantly greater in longterm cover crop plots than in those without. Yet another long-term cost savings from cover cropping for Ontario grain corn producers is the reduced rate of nitrogen fertilizer needed. In this project, the team is using '15N-enriched fertilizer' to trace the pathway of applied nitrogen. "Without the 15N tracer, we don't know if nitrogen in the crop came from the fertilizer or frommineral nitrogen in the soil," explains Peng. "We applied 15N-enriched fertilizer at cover crop planting, so we will know how much fertilizer the cover crops took up in shoots and roots and how much remains in the soil to the three-foot depth in the late fall and following spring. Then, we can follow nitrogen fertilizer transfer into the following corn crop in terms of the grain, stover, roots and soil. This helps us understand how cover crops take up nitrogen and how that nitrogen is transferred to the following crop." As to which cover crops might eventually be recommended once this project is complete, Peng says, "in this experiment, there is no compelling evidence to recommend one specific cover crop over another. Thus, we suggest farmers pick the one that fits into their rotation and meets their goals." The most exciting part of this project for Peng is having long-term versus first-time cover cropping versus no cover cropping in the same field. "We can look at different cover crop species and also compare different time scales," she says. "We are excited to provide Ontario cover crop data to support farmer decision-making." LEGUME-BASED COVER CROPS In another cover crop project, Dr. Kim Schneider, graduate student Daniel Colcuc, and Dr. Elizabeth Lee (with colleagues Dr. John Lauzon and Jake Munroe, OMAFRA soil management specialist) are determining the effectiveness of legume-based cover crops in providing nitrogen benefits to a subsequent corn crop. The researchers note that red clover that is frost-seeded in the spring into a standing continued on page 12 These research projects received funding from Grain Farmers of Ontario. Genes on-line. For genes that fit your farm®, visit secan.com Genes that fit your farm®is a registered trademark of SeCan. winter wheat crop has been shown to demonstrate significant nitrogen credit benefits to a subsequent corn crop in southwestern Ontario. However, red clover stands frequently suffer from non-uniformity across a field, which has reduced their uptake by farmers. Annual cover crops planted after winter wheat harvest, specifically those that include legumes, are a potentially very good alternative to red clover — providing a nitrogen credit to the following crop in the same way. One legume cover crop option, Balansa clover, is available in the Ontario market and is being promoted for its nitrogen-fixation capabilities, but little data is available on its ability to supply nitrogen when planted as a lateseason cover crop. Colcuc says that so far, Balansa clover and the other annual legumes they chose to plant — berseem clover and Austrian winter peas (AWP) — had very mixed results when planted
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