LAUSR

Erianthus arundinaceus, a warm-season perennial species in the Gramineae family, is currently being considered as a bioenergy crop candidate due to its capacity for high yields. Several experiments to explore this possibility have been conducted in Nasushiobara, Japan, where the mean minimum air temperature in January over the last three decades has been − 4.4 °C. Some accessions and breeding lines have demonstrated overwintering abilities, and annual dry matter yields of up to 52 t ha−1 were recorded in the 7th year after planting. Cutting to a 0.05-m height in February contributed more to subsequent regrowth and yield than did similar cutting in November. However, when performed in November, cutting to a 0.3-m height was more beneficial to subsequent regrowth and yield than cutting to a 0.05-m height. Allowing the foliage to run dry during winter led to a dry (approximately 70% dry matter ratio) biomass harvest in late winter. During winter, nutrient remobilization within the plants decreases nutrient removal from the soil. Although nitrogen fertilizer use efficiency was quite high (60%), only 20% of the nitrogen in an individual plant in the 2nd year after planting originated from fertilizer. This was likely due to a large amount of nitrogen obtained from non-fertilizer sources, i.e., soil and stored in the stubble from the previous harvest. Future experiments should focus on designing a fertilizer application program that could lead to sustainable and long-term high-yield E. arundinaceus biomass production in temperate zones.