A Single-pass Reduced Tillage Technique for the Establishment of Short-Rotation Poplar (Populus spp.) Plantations

In Italy, there has been a significant increase of the areas cultivated with short-rotation forestry (SRF) poplar (Populus spp.) for the production of lignocellulosic biomass. This species has been generally introduced on soils managed with conventional farming practices that led to the formation of a hardpan. This constitutes a serious obstacle for root development and water availability, which affect the successful establishment of the plantation. To this end the Unit of Agricultural Engineering of the Agricultural Research Council (CRA-ING) has developed a new system for reduced tillage (RT), to be used during the establishment of SRF poplar. This new system aims at breaking the tillage pan and at reducing both traffic intensity and site preparation cost. A new machine has been developed, which is based on a commercial rotary plough, suitably modified by adding a shank subsoiler. This machine can perform both deep soil ripping and surface ploughing in a single pass, treating narrow strips where poplar cuttings are to be planted. The study compared conventional tillage (CT) with RT, showing that latter allowed a dramatic reduction of the number of field operations and of all related problems, while creating better conditions for poplar rooting without meaningful effects on yield.