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Abstracts of Publications Michael S. Williams, Kenneth L. Cormier, Ronald G. Briggs, and Donald L. Martinez. Evaluation of the Barr & Stroud FP15 and Criterion 400 Laser Dendrometers for Measuring Upper Stem Diameters and Heights. FOR. Sci. 45(l):53-61   Calibrated Barr & Stroud FP15 and Criterion 400 laser dendrometers were tested for reliability in measuring upper stem diameters and heights under typical field conditions. Data were collected in the Black Hills National Forest, which covers parts of South Dakota and Wyoming in the United States. Mixed effects models were employed to account for differences between users of the dendrometers and to test for significant differences between the heights and diameters measured indirectly (by dendrometer) and directly (by caliper and linear tape). The location at which measurements were taken on each tree was determined by paint marks along the bole. No significant differences between users were found. The Barr & Stroud consistently overestimated diameters by approximately 0.3 cm (0.1 in). Unbiased estimates of diameter were obtained with the Criterion 400. For height measurements, neither the Barr & Stroud nor the Criterion 400 produced unbiased measurements. The effect of distance to the base of the tree and height of the diameter measurement on the variability of the measurements was also studied. As distance increased, the variability of diameter measurements increased for both dendrometers. For the measurement of height, only the Barr & Stroud exhibited an increase in the variability of measurements with increasing distance. After correcting the data for their biases, taper equations were fitted to them and analyzed. The equations generated from the Barr & Stroud were not significantly different from those generated from direct measurement, unlike the Criterion 400 where taper equations generated were statistically different. A brief study of the effects of familiarity with each dendrometer indicated that the measurement error and variability decreased as the user became more familiar with the Criterion. This was not the case for the Barr & Stroud. Robert O. Curtis, Dean S. DeBell, Constance A. Harrington, Denis P. Lavender, J. Bradley St. Clair, John C. Tappeiner, and John D. Waistad, 1998. Silviculture for Multiple Objectives in the Douglas-fir Region. Gen. Tech. Rep. PNW-GTR-435. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 123 p. Silvicultural knowledge and practice have been evolving in the Pacific Northwest for nearly a century. Most research and management activities to date have focused on two major topics: (1) methods to regenerate older, naturally established forests after fire or timber harvest; and (2) growth and management of young stands. Today forest managers can reliably regenerate the major conifer and hardwood species under most conditions by using combinations of natural and artificial regeneration. They also can control stand density and species composition and growth of individual trees, thereby influencing stand structure. Available growth models can reasonably predict the outcome of growing conifer stands under a range of densities, species composition, and management scenarios, providing tree numbers by size class as well as crown characteristics and wood yields. Most silvicultural efforts have been financed through and directed toward production of wood. Although some other values have been produced or improved in conjunction with such activities, public interest and emphasis on nontimber values have increased. It has become apparent that some values are not benefited by silvicultural practices aimed solely at wood production. In most situations, however, desired nontimber values can be enhanced by silvicultural measures implemented for their direct benefit or by some modifications of practices applied primarily to produce wood. We discuss the historical development of silviculture in the Pacific Northwest and review the silvicultural practices currently available to forest managers. We then point out how these practices can be structures (including those usually associated with old forests) and pleasing scenery, while also producing wood products. Most of the silvicultural knowledge needed to design and implement regimes for integrated production of these multiple values already exists.   Back to Newsletter The CFR home page is also a good source for other forestry links. It can be reached by going to: http://www.cfr.washington.edu/If you have any links, articles or abstracts you would like to see included in the SMC newsletter, please e-mail them to: moshea@u.washington.edu   SMC Home SMC PublicationsEvents CalendarStaff and Members Other Web Sites College of Forestry