Harvesting techniques for Sorghum bicolor in northern Italy

Over the last years several field trials have been carried out in Italy in order to find suitable energy crop species and select specific varieties for large scale biomass production. Currently, Sorghum bicolor is considered to be an interesting and promising biomass crop for Northern Italy due to its abundant biomass production as well as its yearly vegetation cycle, which is easier to approach by most of the farmers compared to the perennial crops, allowing more flexibility in farm management. A 20 hectares field trial was cultivated with Sorghum bicolor during the summer 2007 in the framework of a project founded by the Emilia-Romagna Region. The aim of the trials was to assess and compare two harvesting chains, one related to biogas production and the other one addressed toward obtaining dried and bailed biomass for a combustion plant. The results demonstrated that the first harvesting method (chopping and loading on dumper) is suitable for collecting wet biomass as biogas production feedstock and it does not display any particular problems even when high efficient harvesting machineries available on the market are used. The second harvesting method (mowing-conditioning-drying-baling) showed some problems related to the short period of time available for the crop in order to achieve the right moisture. It also brought to excessive biomass losses.