Efficient harvest lines for Short Rotation Coppices (SRC) in agriculture and agroforestry.

Wood from short rotation coppice (SRC) such as poplar, willow and black locust is a promising option for the sustainable production of biofuels and biomaterials. Provided that production technologies, logi stic chains and end user structures are well designed in farmers' regional structures, these cropping systems may provide a secure source of income. One of the key problems at present is the lack of knowledge and powerful harvest machinery at practice. Although a lot of machines were developed and tested during the last 30 years, only a few have exceeded the prototype stage. Analysing the process chain for SRC, chip lines seem to be most cost-efficient for harvest, and the modification of forage harvesters for SRC is a promising option. But the high machine weight of forage harvesters is a serious disadvantage due to the limited trafficability of harvest plots in winter. Furthermore, for economic operation of these expensive harvest systems cultivation areas of more than 300 ha are required. Therefore, ATB has developed a simple and low weight tractor-mounted mower-chipper for medium sized standard tractors (75 -150 kW) together with the company JENZ (Germany). The chipper is designed for flexible harvest of wood from SRC and Agroforestry (max. stem diameter 15 cm). The total weight of the harvester (tractor and chipper) is less than 50% of the forage harvester combination resulting in much more flexible field operation and lower harvest costs. The machine has been successfully tested in the last two harvest seasons and is on the market available now.