USDA Forest Service

RMRS Black and White Graphic ElementInterior West Forest Inventory & Analysis


Forest Inventory & Analysis
507 25th Street
Ogden, UT 84401-2450

(801) 625-5407

United States Department of Agriculture Forest Service.

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Data Collection - Fieldwork Description

Who and Where:

map of Interior West region

The Interior West Forest Inventory and Analysis (IW-FIA), conducts forest resource inventories in the Interior West States of Arizona, Colorado, Idaho, Montana, Nevada, New Mexico, Utah, and Wyoming.




Image illustrating the field plot layout design

Our unit inventories the forests of the interior West using a two-phase sample.

In phase 1 (remote sensing), we use satellite imagery and aerial photographs to determine forest area in each State. In phase 2 (field plots), we visit a selection of the forested acres identified in phase 1 to further describe the forests. On all of our field plots we gather quantitative and qualitative measurements that describe: tree measurements and characteristics, counts of tree regeneration, general land use, and general stand characteristics (such as forest type, stand age, and disturbance). In addition, changes in land use and general stand characteristics as well as estimates of growth, mortality, and removals are determined by revisiting plots from the previous time period.

On a subset of the field plots, we collect a more extensive set of data during the growing season. These measures relate to forest ecosystem function, condition, and health. These measurements can be grouped into the following categories: crown conditions, soil erosion potential, soil chemical and physical analyses, lichen communities, vegetation diversity and structure, and down woody debris.

General Fieldwork Description:

data collection

Field crews are composed of 2 to 3 individuals who are responsible for conducting forest resource/health inventories. Field crews locate new or previously established sample sites using GPS and aerial photograph baseline techniques; measure and classify attributes of forest conditions and health including: tree species, diameter, age, height, crown condition; lower vegetation species, cover, structure; site conditions including ground cover, lichen community, habitat type, soils; and other resources conditions including wildlife cover, snags, and recreation use. Individuals are required to carry 30-35 pounds of gear during daily fieldwork and a full backpack (up to 60 pounds) on backpacking trips.


Field sites are often located in remote and rugged country. Duties may require extensive foot travel with a heavy backpack over arduous terrain during inclement weather with exposure to a variety of hazardous conditions. Hikes of 3-5 miles per day in steep country are typical. Duties may require extended stays in backcountry environments (camping). Duties may require accessing remote areas by alternative modes of transportation including but not limited to: 4-wheel drive vehicles, ATV’s, helicopters, boats, and horses.

USDA Forest Service - RMRS - Forest Inventory & Analysis
Last Modified: Saturday, 15 October 2016 at 18:39:12 CDT

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