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• 1. [Article] Early Selection for Improving Volume Growth in Coastal Douglas-fir Breeding Programs

  This is the publisher’s final pdf. The published article is copyrighted by J. D. Sauerländer's Verlag and can be found at: http://www.sauerlaender-verlag.com/index.php?id=18.

  Citation × Citation Citation Abstract Copy Title: Early Selection for Improving Volume Growth in Coastal Douglas-fir Breeding Programs Author: Ye, T. Z., Jayawickrama, K. J. S. This is the publisher’s final pdf. The published article is copyrighted by J. D. Sauerländer's Verlag and can be found at: http://www.sauerlaender-verlag.com/index.php?id=18. Title: Early Selection for Improving Volume Growth in Coastal Douglas-fir Breeding Programs Author: Ye, T. Z., Jayawickrama, K. J. S. This is the publisher’s final pdf. The published article is copyrighted by J. D. Sauerländer's Verlag and can be found at: http://www.sauerlaender-verlag.com/index.php?id=18. Close

• 2. [Article] Effects of pruning on wood density and tracheid length in young Douglas-fir

  To study whether pruning young Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco var. menziesii) hastens the transition from juvenile to mature wood, we investigated the effects on wood properties in an ...

  Citation × Citation Citation Abstract Copy Title: Effects of pruning on wood density and tracheid length in young Douglas-fir Author: Gartner, B. L., Robbins, J. M., Newton, M. To study whether pruning young Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco var. menziesii) hastens the transition from juvenile to mature wood, we investigated the effects on wood properties in an intensively managed young plantation in the Coast Range of Oregon. Ten years after trees were pruned to a fixed height (3.4 or 5.5 m), we investigated the effects on wood density (in 12 trees per pruning treatment, two or three treatments per age class, three age classes, and two heights for a total of 168 cores) and tracheid length (in four trees per treatment, one height and age class only, for 12 trees total). The trees were 13, 16, and 18 years old when pruned in 1988. Removal of 50% of the live crown in young trees caused a small one-year decline in growth ring width at breast height, but removal of 30% of the live crown did not. In partial contrast, pruning caused no detectable effect on wood density at breast height, presumably because the branches were in the lower crown, and were not contributing much to the growth of the bole. Pruning caused a small increase in wood density at the upper height (5.3 m) in the youngest age class (for which this 5.5 m pruning would be removing vigorous live branches at this height) but not in the medium age class (for which the pruning would be removing lower live crown at this height) or in the oldest age class (for which there would have been no live branches at 5.5-m). Pruning the youngest trees caused a 3–4 year increase in tracheid length at breast height. In summary, pruning had very small or no effect on growth ring width, density, or tracheid length; but the effects that it had were the ones expected if pruning accelerated the transition from juvenile to mature wood. The larger benefit of pruning, especially if done early in rotation, is to shorten branch healing time and provide for a longer period of clear wood production. Title: Effects of pruning on wood density and tracheid length in young Douglas-fir Author: Gartner, B. L., Robbins, J. M., Newton, M. To study whether pruning young Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco var. menziesii) hastens the transition from juvenile to mature wood, we investigated the effects on wood properties in an intensively managed young plantation in the Coast Range of Oregon. Ten years after trees were pruned to a fixed height (3.4 or 5.5 m), we investigated the effects on wood density (in 12 trees per pruning treatment, two or three treatments per age class, three age classes, and two heights for a total of 168 cores) and tracheid length (in four trees per treatment, one height and age class only, for 12 trees total). The trees were 13, 16, and 18 years old when pruned in 1988. Removal of 50% of the live crown in young trees caused a small one-year decline in growth ring width at breast height, but removal of 30% of the live crown did not. In partial contrast, pruning caused no detectable effect on wood density at breast height, presumably because the branches were in the lower crown, and were not contributing much to the growth of the bole. Pruning caused a small increase in wood density at the upper height (5.3 m) in the youngest age class (for which this 5.5 m pruning would be removing vigorous live branches at this height) but not in the medium age class (for which the pruning would be removing lower live crown at this height) or in the oldest age class (for which there would have been no live branches at 5.5-m). Pruning the youngest trees caused a 3–4 year increase in tracheid length at breast height. In summary, pruning had very small or no effect on growth ring width, density, or tracheid length; but the effects that it had were the ones expected if pruning accelerated the transition from juvenile to mature wood. The larger benefit of pruning, especially if done early in rotation, is to shorten branch healing time and provide for a longer period of clear wood production. Close

• 3. [Article] Density, ages, and growth rates in old-growth and young-growth forests in coastal Oregon

  We studied the ages and diameter growth rates of trees in former Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) old-growth stands on 10 sites and compared them with young-growth stands (50-70 years ...

  Citation × Citation Citation Abstract Copy Title: Density, ages, and growth rates in old-growth and young-growth forests in coastal Oregon Author: Huffman, David W. (William), 1962-, Tappeiner, John C, Spies, Thomas A, Marshall, David, Bailey, John D We studied the ages and diameter growth rates of trees in former Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) old-growth stands on 10 sites and compared them with young-growth stands (50-70 years old, regenerated after timber harvest) in the Coast Range of western Oregon. The diameters and diameter growth rates for the first 100 years of trees in the old-growth stands were significantly greater than those in the young-growth stands. Growth rates in the old stands were comparable with those from long-term studies of young stands in which density is about 100-120 trees/ha; often young-growth stand density is well over 500 trees/ha. Ages of large trees in the old stands ranged from 100 to 420 years; ages in young stands varied by only about 5 to 10 years. Apparently, regeneration of old-growth stands on these sites occurred over a prolonged period, and trees grew at low density with little self-thinning; in contrast, after timber harvest, young stands may develop with high density of trees with similar ages and considerable self-thinning. The results suggest that thinning may be needed in dense young stands where the management objective is to speed development of old-growth characteristics. Title: Density, ages, and growth rates in old-growth and young-growth forests in coastal Oregon Author: Huffman, David W. (William), 1962-, Tappeiner, John C, Spies, Thomas A, Marshall, David, Bailey, John D We studied the ages and diameter growth rates of trees in former Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) old-growth stands on 10 sites and compared them with young-growth stands (50-70 years old, regenerated after timber harvest) in the Coast Range of western Oregon. The diameters and diameter growth rates for the first 100 years of trees in the old-growth stands were significantly greater than those in the young-growth stands. Growth rates in the old stands were comparable with those from long-term studies of young stands in which density is about 100-120 trees/ha; often young-growth stand density is well over 500 trees/ha. Ages of large trees in the old stands ranged from 100 to 420 years; ages in young stands varied by only about 5 to 10 years. Apparently, regeneration of old-growth stands on these sites occurred over a prolonged period, and trees grew at low density with little self-thinning; in contrast, after timber harvest, young stands may develop with high density of trees with similar ages and considerable self-thinning. The results suggest that thinning may be needed in dense young stands where the management objective is to speed development of old-growth characteristics. Close

• 4. [Article] Do Douglas-fir branches and roots have juvenile wood?

  We sampled boles, branches, and roots of four Douglas-fir (Pseudotsuga menziesii var. menziesii) trees to learn a) whether branches and roots have a zone of juvenile wood, defined as a zone with progressive ...

  Citation × Citation Citation Abstract Copy Title: Do Douglas-fir branches and roots have juvenile wood? Author: Peterson, M. G., Lachenbruch, B., Dietterich, H. R. We sampled boles, branches, and roots of four Douglas-fir (Pseudotsuga menziesii var. menziesii) trees to learn a) whether branches and roots have a zone of juvenile wood, defined as a zone with progressive changes in wood density and/or tracheid length from the pith outward at successively greater cambial ages, and if so, b) whether the radial patterns in branches and roots are similar to those in boles. Samples came from the following positions: bole, 30 cm aboveground; branch, 30 cm outward on the lowest live branch, and root, 1–3 m from the bole. Average sample cambial ages were bole, 60 years; branch, 30 years; and root, 48 years. Roots and branches had higher density wood than did the bole at the positions studied, and roots had the longest tracheids followed by the bole and then the branches. All three positions exhibited juvenile wood but with different radial patterns. All positions had their highest density near the pith, which was followed by a steep decline in the boles and a more gradual decline in the roots and branches. Boles and roots, but not branches, then showed an increase in density after this decline. Boles and branches had short tracheids near the pith followed by a gradual increase to an asymptotic value. In contrast, tracheid length in roots was relatively constant from pith to bark, although there was a dip of about 20% from about cambial ages 14 to 24. This study shows that the vascular cambium of this species is not constrained to produce one sole radial pattern of wood properties as it matures. The presence of different radial patterns in boles, branches, and roots supports the hypothesis that juvenile wood in the bole is an adaptive feature rather than an unavoidable developmental consequence. Further work should investigate more fully the different physiological or mechanical roles of the various wood types within the context of the position in the tree at which they occur. Title: Do Douglas-fir branches and roots have juvenile wood? Author: Peterson, M. G., Lachenbruch, B., Dietterich, H. R. We sampled boles, branches, and roots of four Douglas-fir (Pseudotsuga menziesii var. menziesii) trees to learn a) whether branches and roots have a zone of juvenile wood, defined as a zone with progressive changes in wood density and/or tracheid length from the pith outward at successively greater cambial ages, and if so, b) whether the radial patterns in branches and roots are similar to those in boles. Samples came from the following positions: bole, 30 cm aboveground; branch, 30 cm outward on the lowest live branch, and root, 1–3 m from the bole. Average sample cambial ages were bole, 60 years; branch, 30 years; and root, 48 years. Roots and branches had higher density wood than did the bole at the positions studied, and roots had the longest tracheids followed by the bole and then the branches. All three positions exhibited juvenile wood but with different radial patterns. All positions had their highest density near the pith, which was followed by a steep decline in the boles and a more gradual decline in the roots and branches. Boles and roots, but not branches, then showed an increase in density after this decline. Boles and branches had short tracheids near the pith followed by a gradual increase to an asymptotic value. In contrast, tracheid length in roots was relatively constant from pith to bark, although there was a dip of about 20% from about cambial ages 14 to 24. This study shows that the vascular cambium of this species is not constrained to produce one sole radial pattern of wood properties as it matures. The presence of different radial patterns in boles, branches, and roots supports the hypothesis that juvenile wood in the bole is an adaptive feature rather than an unavoidable developmental consequence. Further work should investigate more fully the different physiological or mechanical roles of the various wood types within the context of the position in the tree at which they occur. Close

• 5. [Article] Stand Structures of Oregon White Oak Woodlands, Regeneration, and Their Relationships to the Environment in Southwestern Oregon

  This is the publisher’s final pdf. The published article is copyrighted by Northwest Scientific Association and can be found at: http://www.northwestscience.org/.

  Citation × Citation Citation Abstract Copy Title: Stand Structures of Oregon White Oak Woodlands, Regeneration, and Their Relationships to the Environment in Southwestern Oregon Author: Gilligan, Laurie A., Muir, Patricia S. This is the publisher’s final pdf. The published article is copyrighted by Northwest Scientific Association and can be found at: http://www.northwestscience.org/. Title: Stand Structures of Oregon White Oak Woodlands, Regeneration, and Their Relationships to the Environment in Southwestern Oregon Author: Gilligan, Laurie A., Muir, Patricia S. This is the publisher’s final pdf. The published article is copyrighted by Northwest Scientific Association and can be found at: http://www.northwestscience.org/. Close

• 6. [Article] Stand development, fire and growth of old-growth and young forests in southwestern Oregon, USA

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier ...

  Citation × Citation Citation Abstract Copy Title: Stand development, fire and growth of old-growth and young forests in southwestern Oregon, USA Author: Sensenig, Thomas, Bailey, John D., Tappeiner, John C. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.elsevier.com/. Title: Stand development, fire and growth of old-growth and young forests in southwestern Oregon, USA Author: Sensenig, Thomas, Bailey, John D., Tappeiner, John C. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.elsevier.com/. Close

• 7. [Article] Fire-mediated pathways of stand development in Douglas-fir/ western hemlock forests of the Pacific Northwest, USA

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Ecological ...

  Citation × Citation Citation Abstract Copy Title: Fire-mediated pathways of stand development in Douglas-fir/ western hemlock forests of the Pacific Northwest, USA Author: Tepley, Alan J., Swanson, Frederick J., Spies, Thomas A. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Ecological Society of America and can be found at: http://esa.org/. Title: Fire-mediated pathways of stand development in Douglas-fir/ western hemlock forests of the Pacific Northwest, USA Author: Tepley, Alan J., Swanson, Frederick J., Spies, Thomas A. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Ecological Society of America and can be found at: http://esa.org/. Close

• 8. [Article] Post-fire tree establishment and early cohort development in conifer forests of the western Cascades of Oregon, USA

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by the author(s) ...

  Citation × Citation Citation Abstract Copy Title: Post-fire tree establishment and early cohort development in conifer forests of the western Cascades of Oregon, USA Author: Tepley, Alan J., Swanson, Frederick J., Spies, Thomas A. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by the Ecological Society of America. The published article can be found at: http://www.esajournals.org/loi/ecsp. Title: Post-fire tree establishment and early cohort development in conifer forests of the western Cascades of Oregon, USA Author: Tepley, Alan J., Swanson, Frederick J., Spies, Thomas A. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by the Ecological Society of America. The published article can be found at: http://www.esajournals.org/loi/ecsp. Close

• 9. [Article] Determination of relative economic weights for multitrait selection in coastal Douglas-fir

  Abstract: Relationships between tree traits and tree value for lumber production were investigated. For the purposes of estimating relative economic weights for use in multitrait selection in coastal Douglas-fir ...

  Citation × Citation Citation Abstract Copy Title: Determination of relative economic weights for multitrait selection in coastal Douglas-fir Author: Adams, W. T., Fahey, Thomas D., Aubry, Carol A. Abstract: Relationships between tree traits and tree value for lumber production were investigated. For the purposes of estimating relative economic weights for use in multitrait selection in coastal Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco var. menziesii), tree height, diameter at breast height, and branch diameter were measured on 164 trees (ages 36–66 years). Increment cores from a subsample (92) of these trees were assayed by X-ray densitometry to determine wood density. Bole volume was derived by summing the log volumes of all logs from each tree. Value of lumber recovered from each tree was determined in a separate mill study using both visual and machine stress rated (MSR) grading rules. Multiple linear regression was used to relate tree value to the growth and wood quality traits. Stem volume and branch diameter significantly influenced tree value under visual grading, with relative economic weights of 0.06 dm3 and –5.22 cm, respectively. Wood density significantly influenced tree value under MSR grading (relative economic weights: 0.06 dm3, –6.69 cm, and 0.06 kg/m3, respectively), where lumber strength is measured more accurately. These regression coefficients can be used directly as economic weights in selection indices. Title: Determination of relative economic weights for multitrait selection in coastal Douglas-fir Author: Adams, W. T., Fahey, Thomas D., Aubry, Carol A. Abstract: Relationships between tree traits and tree value for lumber production were investigated. For the purposes of estimating relative economic weights for use in multitrait selection in coastal Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco var. menziesii), tree height, diameter at breast height, and branch diameter were measured on 164 trees (ages 36–66 years). Increment cores from a subsample (92) of these trees were assayed by X-ray densitometry to determine wood density. Bole volume was derived by summing the log volumes of all logs from each tree. Value of lumber recovered from each tree was determined in a separate mill study using both visual and machine stress rated (MSR) grading rules. Multiple linear regression was used to relate tree value to the growth and wood quality traits. Stem volume and branch diameter significantly influenced tree value under visual grading, with relative economic weights of 0.06 dm3 and –5.22 cm, respectively. Wood density significantly influenced tree value under MSR grading (relative economic weights: 0.06 dm3, –6.69 cm, and 0.06 kg/m3, respectively), where lumber strength is measured more accurately. These regression coefficients can be used directly as economic weights in selection indices. Close

• 10. [Article] Focus on Forestry ; Winter 1998

  magazine of the OSU College of Forestry

  Citation × Citation Citation Abstract Copy Title: Focus on Forestry ; Winter 1998 Author: Roorbach, Ashley, Wells, Gail, Brown, George, Oregon State University. College of Forestry, White, Seth magazine of the OSU College of Forestry Title: Focus on Forestry ; Winter 1998 Author: Roorbach, Ashley, Wells, Gail, Brown, George, Oregon State University. College of Forestry, White, Seth magazine of the OSU College of Forestry Close