Evaluation of Winter and Spring Canola in Dairy Farm Rotations for On-Farm Fuel and Dairy Cattle Feed.

We are evaluating growing canola (Brassica napus L.) for dairy cattle feed and fuel for a straight vegetable oil tractor in the Penn State Sustainable Dairy Cropping Systems project. In 2010- 2013, we compared winter and spring canola in a nested split-split-plot design with four replications. Winter or spring canola was planted in crop rotations that compare either pest or manure management strategies. Winter canola was planted in late summer in the pest rotation after terminating alfalfa (Medicago sativa L.) with either a burn-down herbicide or tillage. In the manure rotation, manure was shallow-disk injected or surface applied in fall before planting a rye (Secale cereale L.) cover crop; then in April, the rye was terminated with an herbicide and spring canola was planted.  Canola plant populations, plant pest damage, seed yield, quantity of cold-pressed oil and canola meal, as well as canola meal protein and fat concentration were compared.  Winter canola yields were higher than spring canola. Winter canola planted after terminating alfalfa with tillage had higher populations and less slug damage than no-till canola planted after herbicide-terminated alfalfa. Spring canola yields did not differ between broadcast and inject manure treatments. A higher proportion of oil was cold-pressed when seed moisture content was lower, resulting in higher quality dairy cattle feed (higher % protein and lower % fat). Economic analyses of producing canola for on-farm fuel and meal in the dairy farm rotations will be presented.