Forest management practices on public lands have changed significantly in the last decade in response to growing concerns that traditional approaches have led to widespread loss and fragmentation of old-growth ecosystems and to declines in the biological diversity associated with late seral forests. New standards and guidelines contained in the Northwest Forest Plan specify the minimum levels and spatial patterns of live trees and coarse woody debris that must be retained on lands subject to timber harvest ("matrix" lands and Adaptive Management Areas). Although these recommendations represent the collective knowledge, experience, and professional judgement of the biologists and ecologists who contributed to the Northwest Forest Plan, the ecological consequences of these new approaches have not been rigorously tested.
In the early 1990s several private research institutions and public interest groups sought federal funding for research to address this need. In 1992, the Pacific Northwest Region (Region 6) of the USDA Forest Service received Congressional direction to establish a major silvicultural experiment in Washington and Oregon "using new forestry and landscape management techniques." The Demonstration of Ecosystem Management Options (DEMO) study evolved as a regional interdisciplinary experiment to examine the responses of diverse groups of forest organisms and processes to variation in the amount or pattern of live trees retained through harvest.