For a while now, I have been collecting the annual data provided by the Maine Forest Service on timber harvest activities in a spreadsheet to try to understand what’s been going on in the nearly 17 million acres of forest in the state of Maine. I recently migrated these data over to Tableau, which is a great data visualization tool for exploring simple and complex datasets.
Exploring these trends is important in my work as I need to identify appropriate baselines by which to compare alternative management and forest product utilization pathways. These comparisons are made to understand implications of potential changes in forest management practices and changing policies on outcomes such as greenhouse gas emissions, timber supply, and wildlife habitat. One example is in our recent paper on the greenhouse gas emissions of wood pellet heat in New England.
There has been a great deal of concern lately about the loss of low-grade markets in the northeast US, and it looks like those market changes are finally starting to show in Maine harvest trends. 2016 shows a big drop in harvest volume and total acreage. Prior to 2016, I think Maine’s timber harvest rates have been buffered by the fact that demand stayed relatively constant for wood coming from Maine – but dropped dramatically for wood coming from neighboring states to Maine mills.
One thing that has always been striking to me is that the changes in harvest acreage over time do not necessarily change the volume being harvested each year, generally between 14 and 16 million tons per year. Perhaps even more interesting is that the volume per acre doesn’t change much even as harvesting practices have shifted from clearcuts to partial harvests and shelterwood harvests. Both trends have implications for future supplies of high-quality timber products – something that Dr. Mark Ducey (UNH Professor of Forest Biometrics) and I explore in a paper published in January 2019.
This is an interactive (and public) data visualization, so have a look!