Miscanthus × giganteus productivity: The effects of management in different environments

Miscanthus × giganteus is a C₄ perennial grass that shows great potential as a high-yielding biomass crop. Scant research has been published that reports M. × giganteus growth and biomass yields in different environments in the United States. This study investigated the establishment success, plant growth, and dry biomass yield of M. × giganteus during its first three seasons at four locations (Urbana, IL; Lexington, KY; Mead, NE; Adelphia, NJ) in the United States. Three nitrogen rates (0, 60, and 120 kg ha^-1) were applied at each location each year. Good survival of M. × giganteus during its first winter was observed at KY, NE, and NJ (79-100%), and poor survival at IL (25%), due to late planting and cold winter temperatures. Site soil conditions, and growing-season precipitation and temperature had the greatest impact on dry biomass yield between season 2 (2009) and season 3 (2010). Ideal 2010 weather conditions at NE resulted in significant yield increases (P < 0.0001) of 15.6-27.4 Mg ha^-1 from 2009 to 2010. Small yield increases in KY of 17.1 Mg ha^-1 in 2009 to 19.0 Mg ha^-1 in 2010 could be attributed to excessive spring rain and hot dry conditions late in the growing season. Average M. × giganteus biomass yields in NJ decreased from 16.9 to 9.7 Mg ha^-1 between 2009 and 2010 and were related to hot dry weather, and poor soil conditions. Season 3 yields were positively correlated with end-of-season plant height (ρ̂ = 0:91) and tiller density (ρ̂ = 0:76). Nitrogen fertilization had no significant effect on plant height, tiller density, or dry biomass yield at any of the sites during 2009 or 2010.