Cost Analysis of Corn Stover Harvested in the Spring

Abstract

Abstract. Corn stover is an abundant biomass, yielding typically more than 8 t dry matter (DM) ha -1 in eastern Canada at the time of grain harvest. It is usually left behind in the field because of wet conditions in the fall, its protective role against erosion and its contribution to organic matter in the soil. However, part of this biomass could be harvested in a dry form in the spring for useful applications such as animal bedding, a solid biofuel or a biomaterial feedstock. In 2009, 2010, and 2011, spring harvest of corn stover was studied in southern QuA©bec. Machinery management data were collected to evaluate the cost of four harvest scenarios. In the first scenario, stover was mowed, raked and baled using a 2.4-m disc mower, a parallel-bar rake, and a large square baler (LSB). In the other three scenarios, stover was mowed, shredded and windrowed simultaneously with a 4.6-m flail-shredder-windrower and harvested either with a large square baler, a large round baler (RB) or a self-loading wagon (SLW). Assuming a harvest period of 2.5 weeks in the spring, the largest amount of stover that could be harvested (687 t DM over 177 ha) was obtained with the SLW. Amounts of 466 to 476 t DM over 131 to 125 ha could be harvested with the round baler and the large square baler, respectively. When bales were sold outside the farm, a fertilizer value of $21.01 t -1 DM was accounted for the removal of P and K contained in the stover. The cost of harvest operations was estimated as $34.30 t -1 DM for scenario 1 (mower, rake, and LSB). It was $32.76, $29.04 and $29.67 t -1 DM for combinations of the flail-shredder-windrower and LSB, RB, and SLW, respectively. Storage costs per t DM in a shed varied considerably because of differences in bulk density: $29.87 for the LSB, $59.44 for RB and $71.85 for SLW. Results should allow effective planning of cost and operations related to dry corn stover harvested in the spring.