An urban forest-inventory-and-analysis investigation in Oregon and Washington

• NLCD land use classes evaluated for post-stratification.
• Estimation by species, diameter, and region examined.
• i-Tree Eco investigated as inventory reporting tool.
• Post-stratification with NLCD was not successful.
• Small sample size limited subgroup inferences.

The U.S. Department of Agriculture (USDA) Forest Service, Forest Inventory and Analysis program recently inventoried trees on 257 sample plots in the urbanized areas of Oregon and Washington. Plots were located on the standard grid (≈1 plot/2428 ha) and installed with the 4-subplot footprint (≈.067 ha with 4 circular subplots). Using these data, we examined: 1) use of the land use classification data from the National Land Cover Database (NLCD) for post-stratification; 2) the resolution of the inventory data to make inferences about subdomains (specifically sub-regions) and subgroups (species and diameter classes); and 3) the i-Tree Eco software as a tool for data compilation, estimation, and reporting.