USDA Forest Service

Forest Inventory and Analysis National Program


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

(703) 605-4177

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FIA Library

Field Guides, Methods and Procedures 

P2 Core Field Guide | P2 Regional Field Guides | Master Tree Species | Regional Invasive Species | P3 Field Methods | Urban Field Guide | Prefield Guide | Glossary of Standard Terms
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National Core Field Guides for Standard (Phase 2) Measurements
Version 9.2 of the FIA field methods guide will be released September 2022. 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 9.1 to version 9.2.

FIA National Field Guide for P2 Plots (version 9.2) (13.8MB)

Older Versions:

Regional Field Guides for Standard (Phase 2) Measurements
All FIA units collect a set of nationally consistent Phase 2 core field data variables which also includes a set of nationally consistent core-optional variables. In addition to these core measurements, each unit also collects information to support and address specific regional issues. Each region combines these regional measurements and procedures with the basic core information to create a regional field guide.

Northern FIA Regional Field Guides

Pacific Northwest FIA Regional Field Guides

Rocky Mountain FIA Regional Field Guides

Southern FIA Regional Field Guides

Master Tree Species List (version 9.2)    -Excel format
This list includes all tree species tallied by FIA. The list can be sorted as needed by the user. 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 9.2.

FIA Master Tree Species List 9.2 (237 KB)

Older Versions:

Combined Regional Invasive Species List (version 9.2, revised May 2023 for RMRS only)    -Excel format
This list includes the invasive species collected in each region; collectively these regional lists form the national master invasive list (see the invasive list flowcharts link for more information). The Northern Research Station has a single list for all States (NRS-all). The Southern Research Station has a list for all States (SRS-all), a list for Florida only (SRS-FL), and a list for west Texas only (SRS-WTX). The Rocky Mountain Research Station has a single list for all States. The Pacific Northwest Research Station has individual lists for Hawaii (PNW-HI), Alaska (PNW-AK), Region 5 (PNW-R5), Washington (PNW-WA), Portland, OR (PNW-Portland), and San Diego, CA (PNW-San Diego). There are also lists for the Pacific Islands: Federated States of Micronesia (FM) (K, P, C, and Y indicate specific Islands: K = Kosrae, P = Pohnpei, C = Chuuk, Y = Yap), Marshall Islands (MH), Northern Mariana Islands (MP), American Samoa (AS), Guam (GU), and Palau (PW). In the lists, R = rural (non-urban) and U = urban.

FIA Master Invasive Species List (version 9.2, May 2023 rev) (40 KB)

Invasive Species List Flowcharts (53 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:

National Urban Prefield Guide:

FIA Glossary of Standard Terms
An alphabetic reference of standard terminology and acronyms used by Forest Inventory and Analysis (FIA) can be found in the FIA Glossary of Standard Terms.

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USDA Forest Service
Last Modified: October 4, 2023

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