Exploring product supply across age classes and forest types
Timber supply modeling has evolved from examining inventory sustainability based on growth/drain relationships to sophisticated inventory and supply models. These analyses have consistently recognized regional, ownership (public/private), and species group (hardwood/softwood) differences. Recognition of product differences is fundamental to market analysis which traditionally focus on sawtimber and pulpwood. This paper explores the link between product demand and distribution of harvest across forest types and age classes through a simple econometric analysis of US Forest Service FIA tree level data for the state of Georgia. Harvest by owner-forest type-age class was found to be correlated with inventory. Some prices response, and a limited response to expected prices was also found, although a much more detailed analysis of expected prices is needed to draw any firm conclusions about the role of price expectations in harvesting. There was support, at least for short term modeling, for using a constant harvest proportion of inventory but limited evidence that oldest stands are harvested first.