PERFORMANCE OF SMALL-SCALE TECHNOLOGY IN PLANTING AND CUTBACK OPERATIONS OF SHORT-ROTATION WILLOW CROPS

Modern bioenergy crops have potential to play a crucial role in the global energy mix, especially under policies to reduce carbon dioxide emissions. The management of short-rotation willow crops involves several operations that deliver biomass for different uses. In commercial-scale operations, high-performance, mostly automated equipment is frequently used; however, in small-scale operations, smallholder farmers adapt traditional agricultural equipment to fit their needs. This study evaluated the field performance of planting and cutback operations in small-scale willow crops using equipment that was characterized by a low level of technological integration. Following the implementation of both operations, the planting work rates ranged from 0.216 to 0.300 ha h(-1), depending on the soil preparation and planting density. Delays significantly reduced the field performance, resulting in gross work rates of 0.149 to 0.230 ha h(-1). By comparison, cutback operations had higher work rates of 2.31 and 2.35 ha h(-1) for gross and net production, respectively. These rates dropped to approximately 1.77 and 2.00 ha h(-1), respectively, due to time spent in headland turns and other delays. Possibilities to improve the field performance depend on good preparation of the soil prior to planting, which includes removal of agricultural residue. In the case of cutback operations, avoiding backward movement of the equipment when additional headland space is available and an improved field layout may shorten the time spent in headland turns. The results indicate that small-scale energy crop plantations can be sustainable in terms of efficiency when unspecialized technologies are used. Therefore, small-scale agriculture can make a positive contribution to climate change mitigation targets.