Download or read book Stand Development After 20 years of Growth in Douglas fir and Red Alder Mixtures written by Brennan T. Garrelts and published by . This book was released on 2009 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study examines the long-term role of interference on stand development of Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) and red alder (Alnus rubra Bong.) planted mixtures in the Central Cascades of Oregon, USA. The two species are common associates in naturally regenerated and planted conifer stands in the Pacific Northwest. Due to red alder's rapid height growth, Douglas-fir is often impeded when in the presence of red alder. However, because of red alder's ability to fix nitrogen and increase soil nutrient cycling rates Douglas-fir development can potentially be enhanced when in red alder presence. The relationship between current stand structure, tree mortality, tree size and varying mixtures of species proportions were examined in this study. Treatments included four proportions of red alder either planted simultaneously with the Douglas-fir or delayed 5-years after initial Douglas-fir planting. The objectives of this study were to determine if species mixtures were capable of a greater yield when compared to monocultures and then to determine which form of interference was taking place within and between species. A long-term replacement series study was established in 1986 to understand the role of interference on two commercially valuable species. Six treatments of each planting time were created with the following proportions (Douglas-fir/red alder, respectively): 1.0/0.0, 0.9/0.1, 0.7/0.3, 0.5/0.5, 0.25/0.75, 0.0/1.0. Each treatment was replicated three times in a randomized complete-block design. Measurement of diameter at breast height (cm) of each stem, total height (m), and number of live/dead stems were determined in 1988-1991, 1993, 1995, 1998 and 2007. Yields of both the 0.5/0.5 simultaneous and delayed treatment mixtures were notably higher than the monocultures. Per-tree basal area, height, and survival decreased for both the Douglas-fir and red alder as the relative density (proportion) of red alder increased in the simultaneously planted mixtures. In the delayed mixtures, Douglas-fir per-tree basal area, height, and survival increased as red alder density increased. Red alder development indicated only minor decreases in survival as its density increased in the delayed treatment mixtures. Competition was the dominant mechanism of stand development for all treatments. In the simultaneously planted treatments the Douglas-fir was driven most by interspecific competition, while red alder development exhibited trends for intraspecific competition. In the delayed planted treatments both species experienced intraspecific competition, although this effect was minor for red alder. These results support the competitive effects of red alder on Douglas-fir and itself when seedlings are established at the same time. The delayed treatments however, showed the importance of density on individual tree development over time.
Download or read book Growth and Development of Red Alder Compared with Conifers in 30 year Old Stands written by Carl M. Berntsen and published by . This book was released on 1961 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Growth and Development of Red Alder Compared With Conifers in 30 Year Old Stands Classic Reprint written by Carl M. Berntsen and published by Forgotten Books. This book was released on 2018-03-17 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: Excerpt from Growth and Development of Red Alder Compared With Conifers in 30-Year Old Stands Early interest in the management of red alder in the coastal forests of Oregon and Washington stimulated the start, in 1935, of a long-term stand-growth and development study. Two 1 - acre plots and two half-acre plots were established on abandoned cleared land where 8 to 12-year-old stands of red alder and conifers were developing. The conifer component consisted of a mixture of Douglas-fir, Sitka Spruce, and western hemlock. Selections and treatments brought about diversified composition of the experimental stands, . As follows: (1) pure alder, unthinned, (2) mixed alder-conifer, unthinned, (3) pure alder, thinned from an alder-conifer stand at age 11 years, and (4) p'ure conifer, thinned from an alder-conifer stand at age 8. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.
Download or read book Case Studies of Red Alder and Sitka Alder in Douglas fir Plantations written by Dan Binkley and published by . This book was released on 1982 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt: Seven case studies of 11 ecosystems were used to examine the effects of nitrogen-fixing alders in Douglas-fir plantations. The first case study quantified nitrogen (N) fixation and aboveground net primary production in a young Sitka alder [Alnus sinuata (Regel) Rydb.] ecosystem. At 5 yr of age, the N fixation (C22H2 reduction) rate of 35 kg ha−1 yr−1 was near the middle of the reported range for this shrubby species. The second case study compared N fixation rates of Sitka alder and red alder (Alnus rubra Bong.) on the same sites. These species exhibited similar nodule activities and had similar nodule:leaf biomass ratios of 7-8%. A mixture of Sitka alder and Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] was estimated to have a current N fixation rate of 20 kg ha−1 yr−1 based on acetylene reduction; N accretion measurements indicated an average N fixation rate of 30 kg ha−1 yr−1 for 23 yr. A mixture of red alder and Douglas-fir on the same site had a current N fixation rate of 130 kg ha−1 yr−1 based on acetylene reduction, with an N accretion rate of 65 kg ha−1 yr−1 for 23 yr. The third case study evaluated the effects of Sitka alder on Douglas-fir growth and nutrition, and on ecosystem production and litterfall. Current Douglas-fir stem growth was 40% greater with Sitka alder, and aboveground ecosystem net primary production was increased 70% with the alder. Litterfall nutrient content was 3 to 7 times greater under the mixed canopy. The fourth and fifth case studies looked at 23 yr-old mixtures of red alder and Douglas-fir in comparison with pure Douglas-fir, on an infertile site and on a fertile site. Red alder had little effect on Douglas-fir size or growth rate on the infertile site, but ecosystem net primary production was tripled. Conversely, net primary production was not increased by red alder on the fertile site, and Douglas-fir size and growth were reduced. The final two case studies evaluated: (1) the conclusions reached in the previous case studies for applicability to red alder/Douglas-fir mixtures in general, and (2) trends in production with stand development up to age 50. These case studies were consistent with the general conclusions of site fertility interactions with red alder/Douglas-fir mixtures. With further stand development, red alder continued to enhance ecosystem production and Douglas-fir growth on infertile sites, with opposite effects on fertile sites. Sitka alder demonstrated a high potential usefulness for interplanting with Douglas-fir, and red alder greatly boosted ecosystem production on infertile sites. Both species merit further development as tools for forest management on N deficient sites.
Download or read book Red Alder written by Robert Leslie Deal and published by . This book was released on 2006 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt: In March 23-25, 2005, an international symposium on red alder was held at the University of Washington Center for Urban Horticulture in Seattle, WA. The symposium was entitled S2Red alder: A State of KnowledgeS3 and brought together regional experts to critically examine the economic, ecological and social values of red alder. The primary goal of the symposium was to discuss new advances in the understanding of red alder biology and silviculture, changing market and nonmarket values, and the current regulatory climate for management of alder. This proceedings includes 14 papers based on oral presentations given at the symposium. These papers highlight some of the key findings from the history, ecology, biology, silviculture and economics sessions presented at the red alder symposium.
Download or read book Fifty year Development of Douglas fir Stands Planted at Various Spacings written by Donald L. Reukema and published by . This book was released on 1979 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Size density Relationship in Pure and Mixed Red Alder Douglas fir Stands and Its Use in the Development of a Growth Model written by Klaus J. Puettmann and published by . This book was released on 1990 with total page 356 pages. Available in PDF, EPUB and Kindle. Book excerpt: The increased interest in red alder (Alnus rubra Bong.) management instigated research in growth and yield and stand development of red alder in pure and mixed red alder/Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) stands. This study had the goa1s of evaluating the accuracy of the currently existing growth and yield tools for red alder and investigating the size-density relationship for pure red alder and Douglas-fir stands and mixed red alder/Douglas-fir stands. The database consisted of long-term remeasured plots in western Oregon and Washington and southwestern British Columbia. The comparison of the data with the red alder yield tables suggested lower accuracy for the Normal Yield Table for Red Alder than the Empirical Yield Table for Predominantly Alder Stands in Western Washington for prediction of both pure and mixed stand yield. Growth projections of the Stand Projection System for pure and mixed red alder/Douglas-fir stands were not accurately enough to ensure a reliable estimate of future stands conditions. The intercept and shape of the size-density trajectory and the relative density at which mortality starts (0.44) for red alder was independent of initial density. The Douglas-fir self-thinning line was above the red alder line but had a shallower slope ( -0.525 for red alder vs.-0.638 for Douglas-fir). The size-density surface for pure and mixed stands exhibited a near-linear region for stands with a high proportion of red alder and a curvilinear portion for stands with a higher proportion of Douglas-fir. Stand density, relative dominance and species proportion were found to be the major determinate of stand development. The information on the size-density relationships and stand development were incorporated into a growth model.
Download or read book Occurrence of Shrubs and Herbaceous Vegetation After Clear Cutting Old growth Douglas fir in the Oregon Cascades written by Vern P. Yerkes and published by . This book was released on 1960 with total page 506 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Early Survival and Growth of Planted Douglas fir with Red Alder in Four Mixed Regimes written by Marshall D. Murray and published by . This book was released on 1986 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book General Technical Report PNW GTR written by and published by . This book was released on 2006 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Height Growth and Site Index Curves for Red Alder written by Constance A. Harrington and published by . This book was released on 1986 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Competitive Interactions in Young Coastal Douglas fir red Alder Mixtures written by Amy T. Grotta and published by . This book was released on 2002 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt: When Douglas-fir and red alder grow in mixture, interactions between the two species can be competitive, facilitative, or a combination of both over time. A number of factors have recently led to increased interest in managing these two species together for commercial production, and ongoing investigations are yielding important information about how interactions between the two species affect stand structure and productivity. Many wood quality attributes are ultimately controlled by physiological processes, which in turn are affected by competition within a forest stand. This research addressed how stand structure in young, mixed red alder/Douglas-fir plantations was associated with variations in growth form and wood quality. Branch attributes and cambial growth patterns in Douglas-fir and stem form attributes in red alder were analyzed as a function of species proportion and timing of establishment in 15-year-old mixed plantations in the Oregon coast range. When the two species were planted simultaneously, only mixed stands with low (10% of total stand density) proportions of red alder had low Douglas-fir mortality. In these stands, red alder stem form was poor, with a high incidence of multiple stems, low live crown bases, and considerable stem lean and sweep. Douglas-fir trees had a relatively short season of cambial growth and many were highly suppressed. When red alder planting was delayed five years, Douglas-fir trees had a short cambial growth season when the proportion of red alder in the stand was high (75%). Douglas-fir crown base height was low when the proportion of red alder was high, but branch sizes were relatively consistent across species proportions. Percent latewood in Douglas-fir was not affected by species proportion. Red alder stem form was consistent across all levels of species proportion. It is suggested that the differences observed are a result of differential juvenile growth rates of the two species and subsequent different levels of light availability to individual tree crowns through stand age 15. Simultaneous planting of the two species at these spacings results in either unacceptable Douglas-fir growth and mortality rates or poor red alder stem form, depending on species proportion. Delayed planting of red alder appears to improve red alder stem form and results in acceptable Douglas-fir wood quality attributes, if red alder proportion is 50% or less. Because these stands are not yet of harvestable size, further monitoring is needed to assess how the patterns of growth and wood quality described would affect eventual product recovery.
Download or read book Comparative Effects of Precommercial Thinning Urea Fertilizer and Red Alder in a Site II Coast Douglas fir Plantation written by Richard E. Miller and published by . This book was released on 1999 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Red Alder written by Norman P. Worthington and published by . This book was released on 1962 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Abstracts of Recent Published Material on Soil and Water Conservation written by and published by . This book was released on 1962 with total page 754 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstracts for Dec. 1954- issued in the Agricultural Research Service's series ARS-41.
Download or read book Growth and Development of Red Alder Compared with Conifers in 30 year old Stands written by Carl M. Berntsen and published by . This book was released on 1961 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:
