Since the 1930s, the U.S. Forest Service has conducted inventories of private lands throughout the United States. In the early days, inventories focused primarily on trees: how much timber was out there? Today's inventory is still about measuring and counting trees, but it also accounts for understory vegetation, down woody material, lichens, damage caused by insects and disease, and more.
Whereas the original inventory design produced resource bulletins about every 10 to 12 years from data collected over a 2- to 3-year period, today's inventory in the Western United States is conducted on a 10-year cycle where 1/10 of the field plots are measured annually on public and private forest land. Data are now posted each year and summary reports are issued every 5 years.
The frequency was directed by Congress through language in the 1998 Farm Bill, according to ecologist Joseph Donnegan, technical editor of the Oregon report and a member of the PNW Research Station's Forest Inventory and Analysis (FIA) Program.
"Instead of the 10-year timber reports we used to produce, we now post data annually and write a report every 5 years that covers a much broader range of topics that regularly appear in the news. The idea was not only to provide data on an annual basis, but to be nationally consistent in how we conduct inventory and monitoring. Previously, different FIA regions were using different methodologies," explains Donnegan. "The results were specific for that region or part of the country, but comparisons and analyses weren't easily made owing to the variety of techniques used. The national Forest Inventory and Analysis Program now uses standard measurement and analysis techniques."
Standardization and the move
|Contact: : Sherri Richardson Dodge|
USDA Forest Service, Pacific Northwest Research Station