Pacific Northwest Research Station

PNW > Research > Large Scale Siviculture Experiments

Large-Scale Silvicultural Experiments In Western Oregon and Washington

Large-scale silviculture experiments (LSSEs) are silviculture experiments conducted at operational scales. As true manipulative experiments, LSSEs are characterized by such fundamental elements of experimental design as randomization, replication, and unmanipulated, “control” treatments. As large-scale experiments, the LSSEs reviewed here are designed to be both spatially and temporally large in scale. The size range of individual LSSE experimental units—typically between 5 and 100 acres, with an average area of approximately 25 acres—falls within that of operational-scale management units on public lands in the Pacific Northwest. Operational-scale experimental units permit inferences drawn from the LSSEs to be directly related to management information needs without having to scale up research results from smaller experimental plots.

The LSSEs reviewed here are also temporally large in scale, with proposed study durations of 20 to 200 years. As silviculture experiments, these LSSEs include at least one experimental treatment that involves thinning or harvesting of trees to develop silvicultural alternatives. A defining characteristic of LSSEs is that a broad range of response variables (e.g., tree species and size structure, small mammals, woody debris, fungi, soils, microclimate, and social perceptions) are measured to characterize the response of the forest ecosystem to the experimental treatments.

Click on the links below for detailed overviews of 12 LSSEs in western Oregon and Washington with which the Pacific Northwest Research Station is substantially involved. (The letters following the study names indicate the location of each study on the map at the right.)

Capitol Forest Study (A)

Clearwater Study (B)

Demonstration of Ecosystem Management Options Study (C)

DMS Initial Thinning Study (D)

DMS Re-Thinning Study (E)

DMS Riparian Buffer Study (F)

Forest Ecosystem Study (G)

Long-Term Ecosystem Productivity Study (H)

Olympic Habitat Development Study (I)

Siuslaw Thinning and Underplanting For Diversity Study (J)

Uneven-Aged Management Project (K)

Young Stand Thinning and Diversity Study (L)

Integrating Science and Experience into Silvicultural Prescriptions and Forest Research

Summary and Presentations from the Workshop held June 14-15, 2007 in Vancouver, Washington. Click the title above or here to read summaries and view slideshow presentations in PDF format.

USDA Forest Service - Pacific Northwest Research Station
Last Modified:  Tuesday, 29 January 2008 at 17:09:43 EST