USDA Forest Service

Forest Inventory and Analysis National Program


Forest Inventory & Analysis
National Office
U.S. Forest Service
1400 Independence Ave., SW
Washington, D.C. 20250-0003

(703) 605-4177

United States Department of Agriculture Forest Service.

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FIA Library

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Field Guides, Methods and Procedures
All download documents are in Acrobat PDF format unless otherwise noted
Field Guides for Standard (Phase 2) Measurements
Version 9.1 of the FIA field methods guide will be released September 2021. It describes the current set of nationally consistent core field procedures used by all FIA units for projects that begin after the date of release. This version of the field guide covers all core and core optional measurements collected on Phase 2 plots (the standard base FIA sample grid, each sample location represents approximately 6,000 acres). Please see the change information in the front of the document for a summary of the changes from version 9.0 to version 9.1.

FIA National Field Guide for P2 Plots (version 9.1) (12.2MB)

Older Versions:

Master Tree Species List (version 9.1)    -Excel format
This list includes all tree species tallied by FIA. The list can be sorted as needed by the user. The Exclusion columns indicate where the species are excluded even though the species is tallied in all other regions. The Past Tally columns indicate how the species were tallied in the region in previous years (AK = Alaska, C = Caribbean, P = Pacific, PNWS = Pacific Northwest South excluding Alaska, R = regional mainland on the region's tally list in field guide version 8.0, and U = urban on the tally list in field guide version 8.0). Species designated Caribbean (C), Pacific (P), and Urban (U) are commonly found in those areas, although species designated for one area may occasionally be found in another. Woodland species designate species where d.r.c. is measured instead of d.b.h. Species designated as being Historic P2 species (P2) were collected as part of the P2 annual inventory, excluding the Caribbean and Pacific Islands, prior to Field Guide version 9.0. Note that the Master Species List is a living document and the list in any field guide version is a snapshot in time of the species code list for a specific data collection period. This is version 9.1.

FIA Master Tree Species List 9.1 (232 KB)

Older Versions:

Field Methods for Forest Health (Phase 3) Measurements
These measurements are collected on a 1/16 subset of the standard base FIA grid plots. Chapter numbers follow the numbers established for the Standard, Phase 2 measurement field guide.

Older Versions:

Field Guides for Urban Measurements
Current and past field guides for FIA's Urban measurements can be found on the Urban FIA Program page.

Field Guides for Prefield Measurements
The field guide for the FIA's national prefield procedures describes the standards, codes, methods, and definitions for FIA prefield data items. The term prefield refers to the data collection items listed within the guide and to the procedures used to measure those items. The objective is to describe CORE FIA prefield procedures that are consistent and uniform across all FIA units.

National Core Prefield Guide (version 6.0p) (403KB)

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USDA Forest Service
Last Modified: June 22, 2021

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