Forest inventories in Oregon include more than trees

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* Oregon's forests span about 30 million acres; about half of Oregon's total land area of 61 million acres.

* Forest land is being converted to other uses particularly near urban areas. The rate of conversion had slowed in the past decade, but it's not clear what protections will remain on rural forest and agricultural land.

* The majority of old-growth forest is now found on federal land, although the current percentage is estimated to be less than half of that existing before Euro-American settlement.

* Data spanning 1953 to 1987 show a decrease in timberland area and volume, but inventories in the late 1990s and 2001-2005 suggest recent increases in timberland acreage and volume.

* Economic activity increased in the forest products industry, with an 8-percent increase in harvest since 2003.

* Private landowners provide most of Oregon's wood products, industry jobs, and timber revenue.

* Ownership is rapidly changing as some industry owners sell their lands to timber investment management organizations (TIMO) or real-estate investment trusts (REIT) who may manage the land for a variety of purposes.

* A single fuel-management prescription does not fit all landscapes in Oregon. Less than half of forested lands are predicted to develop crown fires, and an even smaller fraction can be expected to develop active crown fire.

* Oregon's forests are a net sink for carbon. More carbon is sequestered in growing wood than is emitted in decaying wood.

The data from the FIA reports are used by state, federal, and private land managers, investors, and others for a variety of purposes including the assessment of fuels and potential fire hazard, biomass and carbon storage, the effects of insects and disease, growth and mortality, wildlife habitat, plant diversity, and the supply of goods and services.

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 to annual data availability occurred through the efforts of client input via blue-ribbon panels. Congress responded with Farm Bill directives and by allocating partial funding to begin progress toward a Forest Inventory and Analysis system that is national in scope.

USDA Forest Service, Pacific Northwest Research Station