Dual Cropping Winter Camelina with Soybean in the Northern Corn Belt

Sustainably balancing biofuel crop production with food, feed, and fiber on agricultural lands will require developing new cropping strategies. Double- and/or relay-cropping winter camelina (Camelina sativa L.) with soybean [Glycine max (L.) Merr.] may be a means to produce an energy and food crop on the same land in a single year. A study was conducted between 2009 and 2011 in west central Minnesota to evaluate yields, seed quality, economics, and within-field energy balance of winter camelinasoybean double-and relay-cropping systems compared with a conventional monocropped full-season soybean. Systems included methods to hasten camelina harvest (e. g., swathing and desiccating) to promote early soybean growth. Camelina seed yields were unaffected by cropping system and ranged from 1.1 to 1.3 Mg ha(-1). Relay-cropped soybean yields were greater than double-cropped soybean and were 58 to 83% of that for the monocropped control. Seed oil and protein content of double-and relay-cropped soybean were comparable to their monocropped counterpart and combined seed oil yield for the dual crop systems was as much as 50% greater. Net economic returns for the relay-crop treatments were competitive with that of the full-season soybean. Moreover, net energy of the relay-crop treatments was generally as high as the sole soybean crop, but energy efficiency (outputs/inputs) was less due to greater inputs. Results indicate that dual cropping of winter camelina with soybean is agronomically viable for the upper Midwest and might be an attractive system to growers seeking a cash cover crop.