Forests at a Glance…
The Forest Resource
At 42 percent (1991) of its total land area, Idaho has the largest proportion of forest land in the Interior West states. Idaho's forests extend from the large, crystal-clear lakes of the Idaho Panhandle, through the rugged central mountains of the Selway-Bitteroot, Frank-Church, and Sawtooth Wilderness areas, past the Snake River plains to the "mountain islands" of Southeastern Idaho. Idaho contains some of the most remote, rugged, and varied forests in the West. Because Idaho forests have high recreational, scenic, habitat, watershed and timber values, it is important to track their condition. Inventory and monitoring efforts conducted by USDA Forest Service present a systematic compilation of forest statistics of the state.

For example, the graph here presents a breakdown of forest cover, or forest type, on all land ownerships from the most recent comprehensive Forest Inventory and Analysis Database (FIADB) available for Idaho’s forest resource completed in 2002 (FIADB cycle 1). This data includes inventories on all land ownerships, but excludes most of the Payette and Salmon National Forests, all of the Targhee National Forest, and most of the National Park Service (includes Yellowstone National Park). A report titled Idaho's Forests, 1991, presents a summary of the most recent inventory data published for Idaho's forest lands. In 2004, Annual Inventories began in the state using a new sampling design called the mapped plot design.

Plot Status and Current Activity

Field crews collect data on Forest Inventory plots and Forest Health plots across Idaho annually. The FIA method consists of 3 inventory phases: a remotely sensed phase (P1) and 2 field phases (P2 and P3). Fieldwork typically begins in May and proceeds into the fall as plots are completed or weather permits. After five years of annual data have been collected, the first 5–year comprehensive report on Idaho forests will be published.
Number of Plots by Plot Type
Annually, there is on average 430 Phase 2 (P2) plots and 23 Phase 3 (P3) plots in Idaho. Phase 3 plots are a subset of P2 plots. In addition to the variables taken on P2 plots, P3 plots collect additional data with an emphasis on forest health.
In addition to this site, other information related to Idaho forest conditions may be found on the websites of federal and state cooperators. Click on the icons below to see what our partners are up to…
USDA Forest Service in Idaho
Data and Table Access
You may find standardized summary tables by going to - Annual Tables. Customized data summaries are available through FIA data retrieval systems.
Other Idaho Reports
A record of previous statewide reporting efforts is shown in the table below. Note that other special reports, brochures, and data tables using FIA data, can be found in a comprehensive list at the Idaho’s Forest Resources link.
Previous Statewide Reports
Title / Link Reference Number *
1996 1991 Idaho Forests, 1991 INT-RB–88
2004 2001 Idaho's Forest Products Industry: A Descriptive Analysis RMRS-RB-4
1987 1981 Idaho's Forest Resources Resource Bulletin INT-39
1962 1954 Timber Resources of Idaho Forest Survey Release No. 3
* USDA Forest Service, Rocky Mountain Research Station publication numbers are shown here. Over the years the name of the Research Station has changed. Previously it was named the Intermountain Forest and Range Experiment Station or the Intermountain Research Station, hence the initials INT in the report number.
Inventory and Monitoring Information
For specific questions related to field procedures, current and past field manuals are available online. These manuals describe the details of plot establishment and description, forest inventory methods, and procedures used for each forest health indicator. Websites for forest health indicators give rationale for the indicator, as well as access to data, analytical procedures, and related publications.

For clients with a general interest in inventory and monitoring work elsewhere, we have compiled a short list of Inventory and Monitoring On the Web. This list comprises agencies and entities with related interests in forest monitoring at various geographic scales, both within the U.S. and internationally, plus some recommended publications for those with a more technical interest in this subject.


Brown, M.J.; Chojnacky, D.C. 1996. Idaho's Forests, 1991. USDA Forest Service, Intermountain Research Station, Resource Bulletin INT-RB-88.

Morgan, T.A.; Keegan,III C.E.; Spoelma, T.P.; Dillon, T.; Hearst, A.L.; Wagner, F.G.; DeBlander, L.T. 2004. Idaho's Forest Products Industry: A Descriptive Analysis. USDA Forest Service, Rocky Mountain Research Station, Resource Bulletin RMRS-RB-4.

Benson, R.E.; Green, A.W.; Van Hooser D.D. 1987. Idaho's Forest Resources. USDA Forest Service, Intermountain Research Station, Resource Bulletin INT-39.

Wilson, A.K. 1962. Timber Resources of Idaho. USDA Forest Service, Intermountain Forest and Range Experiment Station, Forest Survey Release No.3.

Interior West Forest Inventory and Analysis
Michael Wilson, Program Manager
USDA Forest Service
507 25th St.
Ogden, Utah 84401
(801) 625-5407