Application of a Sugarcane Harvester for Harvesting of Willow Trees Aimed at Short Rotation Forestry: an Experimental Case Study in Japan

An experiment on the growing and harvesting of willow trees aimed at short rotation forestry was conducted in northern Japan. Willows were harvested using a sugarcane harvester from southern Japan during its agricultural off-season. The growing experiment showed the high potential of willow plantations to produce woody biomass of more than 10 dry-t/ha/y. The harvesting experiment showed that space for turning around, one line in one row as a planting method, a growing cycle of three years, and an extractor fan in the harvester are necessary for mechanical harvesting. Mechanical harvesting was considered to have little influence on willow regeneration provided that the machine cut reasonably well-grown trees. The system performance of harvesting and collecting willow billets in a hypothetical model field was calculated as 22.4 m^3/h, suggesting the feasibility of supplying low-cost wood chips.