The impact of wood pellet manufacturing on United States southern timberlands

Abstract

Global wood pellet production grew from an estimated 1.7 million metric tons in 2000, to 35.4 million metric tons in 2018. U.S. mills established over this period account for a large share of new supply triggered by renewable energy targets set by the European Union (EU). There is concern over the potential impacts of exponential growth in wood pellet supply on US forests. We offer a systematic quantitative analysis to assess the effects of wood pellet production on forest conditions within wood pellet mill procurement areas. We rely on plot-level information from the US Forest Inventory and Analysis (FIA) database to estimate changes in forest conditions (e.g. trees per hectare, carbon in trees, cubic-meter volume) between inventory years 2000 and 2017 across Southeastern US States. Using spatial analysis and panel-regression for samples of timberland plots we attempt to discern pellet production effects associated with pellet mill size and location. Propensity score matching was used as a resampling technique to select a subset of FIA plots to control for the non-random process of pellet mill sitting. Panel regression models controlled for various anthropogenic and natural factors to measure the net impact of wood pellet production on average plot-level forest conditions. Overall, we find increased carbon stocks and some evidence of increased removals associated with wood pellet production. This research will contribute to a growing body of knowledge related to the sustainability and future prospects of wood energy and wood pellets.