The Forest Inventory and Analysis Database User Guide (NFI)

This document is based on previous documentation of the nationally standardized Forest Inventory and Analysis database (Hansen and others 1992; Woudenberg and Farrenkopf 1995; Miles and others 2001; Woudenberg and others 2010). Documentation of the structure of the Forest Inventory and Analysis database (FIADB) as well as codes and definitions is provided. This database provides a consistent framework for storing forest inventory data across all ownerships for the entire United States, including many territories. These data are available to the public. 

Older versions of the FIADB User Guide (NFI) are available HERE.