about the data
Pine Chant features tree-ring growth data from twelve individual Arizona trees, representing three species: Pinus edulis (Colorado pinyon), Pinus ponderosa (Ponderosa pine), and Pseudotonga menziesii (Douglas fir). This data is visualized in the images below. (Courtesy Dr. Kelly Hielman)
Many thanks to the U.S. Forest Service’s Forest Inventory and Analysis (FIA) Program for allowing us to use tree-ring data collected in the FIA’s forest monitoring plot network.
The FIA Program collects, analyzes, and reports information on the status, trends, and condition of America’s forests. Phase 1 of this program collects data in the form of aerial photographs and satellite imagery. Phases 2 and 3 are accomplished in the field using a fixed plot design, which consists of a cluster of four circular subplots spaced out in a fixed pattern (see .
This plot design is used to collect data at one field sample site for every 6000 acres of US forestland. Field crews collect data on forest type, site attributes, tree species, tree size, and overall tree condition on accessible forest land. A subset of Phase 2 sample plots are measured for a broader suite of forest health attributes. These attributes include tree crown conditions, lichen community composition, understory vegetation, down woody debris, and soil attributes. There is approximately one Phase 3 plot for every 96,000 acres of US forestland.
—Excerpted from FIA Sampling and Plot Design Fact Sheet by Bill Burkman, USDA Forest Service, 2005.
