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Abstract
The U.S. Department of Agriculture Forest Service Forest Inventory and Analysis Program (FIA) uses a field plot design that incorporates multiple sample selection mechanisms. Not all of the five FIA units currently use the entire suite of available sample selection mechanisms. These sampling selection mechanisms could be described in a number of ways with respect to the optional mechanism known as the annular plot. The annular plot is an auxiliary sampling mechanism intended for sampling rare attributes of interest. One explanation is that the subplot, which samples all trees greater than or equal to 5 in diameter at breast height (d.b.h.), is surrounded by an annular plot, concentric with the subplot for the estimation of rare but regionally important events.
Parent Publication
Citation
Roesch, Francis A. 2007. Location uncertainty and the tri-areal design. In: McRoberts, Ronald E.; Reams, Gregory A.; Van Deusen, Paul C.; McWilliams, William H., eds. Proceedings of the seventh annual forest inventory and analysis symposium; October 3-6, 2005; Portland, ME. Gen. Tech. Rep. WO-77. Washington, DC: U.S. Department of Agriculture, Forest Service: 221-226.