Log sampling methods and software for stand and landscape analyses [report]

Lisa J. Bate, Torolf R. Torgersen, Michael J. Wisdom, Edward O. Garton, Shawn C. Clabough
2008 unpublished
OR 97850; Edward O. Garton is a professor, Fish and Wildlife Resources Department, University of Idaho, Moscow, ID 83844; Shawn C. Clabough is a software and Web developer, 686 Fairview Drive, Moscow, ID 83843. Cover Photos clockwise from top left: American marten in log (by Evelyn Bull); hollow log (by Lisa Bate); salamander on log (by Lisa Bate); early-seral forest with logs (by Lisa Bate). The Forest Service of the U.S. Department of Agriculture is dedicated to the principle of multiple use
more » ... le of multiple use management of the Nation's forest resources for sustained yields of wood, water, forage, wildlife, and recreation. Through forestry research, cooperation with the States and private forest owners, and management of the National Forests and National Grasslands, it strives-as directed by Congress-to provide increasingly greater service to a growing Nation. The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, age, disability, and where applicable, sex, marital status, familial status, parental status, religion, sexual orientation, genetic information, political beliefs, reprisal, or because all or part of an individual's income is derived from any public assistance program. (Not all prohibited bases apply to all programs.) Persons with disabilities who require alternative means for communication of program information (Braille, large print, audiotape, etc.) should contact USDA's TARGET Center at (202) 720-2600 (voice and TDD). To file a complaint -9410 or call (800) 795-3272 (voice) or (202) 720-6382 (TDD). USDA is an equal opportunity provider and employer. Abstract Bate, Lisa J.; Torgersen, Torolf R.; Wisdom, Michael J.; Garton, Edward O.; Clabough, Shawn C. 2008. Log sampling methods and software for stand and landscape analyses. Gen. Tech. Rep. PNW-GTR-746. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 93 p. We describe methods for efficient, accurate sampling of logs at landscape and stand scales to estimate density, total length, cover, volume, and weight. Our methods focus on optimizing the sampling effort by choosing an appropriate sampling method and transect length for specific forest conditions and objectives. Sampling methods include the line-intersect method and the strip-plot method. Which method is better depends on the variable of interest, log quantities, desired precision, and forest conditions. Two statistical options are available. The first requires sampling until a desired precision level is obtained. The second is used to evaluate or monitor areas that have low log abundance compared to values in a land management plan. A minimum of 60 samples usually are sufficient to test for a significant difference between the estimated and targeted parameters. Both sampling methods are compatible with existing snag and large tree sampling methods, thereby improving efficiency by enabling the simultaneous collection of all three components-snags, large trees, and logs-to evaluate wildlife or other resource conditions of interest. Analysis of log data requires SnagPRO, a user-friendly software application designed for use with our sampling protocols. Default transect lengths are suggested for both English and metric measurement systems, but users may override default values for transect lengths that better meet their specific sampling designs. SnagPRO also analyzes wildlife snag and large tree data. * Users should be aware that in harvested stands composed of mainly short log lengths and small diameters with only a few large logs, the SPM may be a better choice for sampling owing to the high variance associated with LIM sampling in these conditions.
doi:10.2737/pnw-gtr-746 fatcat:auszk4pooje37nsxutoyumhzma