Harvesting systems and costs for short rotation poplar
The objective of this review is to compare the cost of coppice and longer rotation poplar harvesting technology. Harvesting technology for short rotation poplar has evolved over the years to address both coppice harvest and single-stem harvest systems. Two potential approaches for coppice harvesting are modified forage harvesters and modified mulcher-balers. Both of these systems effectively handle multistemmed feedstock. Total harvesting cost to roadside likely ranges from $11 to $15 Mg green. The most significant harvesting constraint with coppice systems is the requirement for dormant season operations. More conventional poplar harvesting at production scales uses forest machines for felling and extraction. The Billion Ton Update report used previous productivity studies to estimate a roadside cost for felling and skidding of about $6 Mg green (unchipped). With chipping cost, single-stem systems are about the same roadside price as coppice harvesting. Other factors such as stand establishment, feedstock storage, and rotation length are more likely to determine an economically optimum management system.