Western Journal of Applied Forestry

Tinnin, Robert, O.

doi: 10.1093/wjaf/16.1.5pmid: N/A

Abstract Boles of 210 residual understory Douglas-fir trees, ranging from uninfected to heavily infected with Douglas-fir dwarf mistletoe, were measured for cylindrical form factor, Girard form class, height-to-diameter ratio, bole profile, and volume. Height-to-diameter ratio and Girard form class were significantly reduced by dwarf mistletoe across the range of infection classes. However, no effect due to infection by dwarf mistletoe was found on cylindrical form factor, and only a slight difference in bole profile between uninfected and heavily infected trees was found. These results suggest that dwarf mistletoe increases bole taper and affects the volume of younger Douglas-fir by affecting tree diameter and height but not by a substantive change in bole profile. West. J. Appl. For.16(1):5–8. Arceuthobium douglasii, Pseudotsuga menziesii, dwarf mistletoe, Douglas-fir, bole taper, volume, environmental management, forest, forest management, forest resources, forestry, forestry research, forestry science, natural resources, natural resource management This content is only available as a PDF. © 2001 by the Society of American Foresters

Sutton,, R.F.;Bedford,, L.;Stordeur,, Linda;Grismer,, Marvin

doi: 10.1093/wjaf/16.1.9pmid: N/A

Abstract Two trials (“Upper Coalmine” and “Mackenzie”) were begun in the 1980s in the Prince George Forest Region, B.C., to evaluate a total of 13 site preparation treatments for establishing interior spruce (Picea glauca × engelmannii) in the Engelmann Spruce-Subalpine Fir and Sub-Boreal Spruce biogeoclimatic zones. Treatments included mounding (with various thicknesses of mineral soil “capping”), patch scarification, blading, disk trenching, and herbiciding. In each trial, five blocks each contained one 48 or 80 tree plot/treatment. Trees were monitored for 10 yr at Mackenzie and 15 yr at Upper Coalmine. Large mounds have had consistent biological success. Tree seedling response to blading was site specific; blading at Mackenzie was not significantly inferior to the best (Ministry mound) treatment, but at Upper Coalmine was no better than the untreated control. West. J. Appl. For. 16(1):9–17. Interior spruce, plantation establishment, site preparation, mounding, British Columbia, environmental management, forest, forest management, forest resources, forestry, forestry research, forestry science, natural resources, natural resource management This content is only available as a PDF. © 2001 by the Society of American Foresters

Omdal, Daniel, W.;Jacobi, William, R.;Shaw, Charles, G.

doi: 10.1093/wjaf/16.1.18pmid: N/A

Abstract An important component of forest ecosystems in the southern Rocky Mountains is the belowground biomass associated with mature stands of ponderosa pine (Pinus ponderosa). Information on root biomass is fundamental to understanding the dynamics of ecological systems and designing studies of those systems. Ponderosa pine trees from a stand in northern New Mexico were cut and their root systems excavated. Biomass of all roots > 0.6 cm in diameter and the belowground portion of the stump was determined on a dry-weight basis. A regression model was constructed using data on breast-height diameter and belowground stump and coarse-root biomass from 42 trees in the stand. Diameter at breast height ranged from 18.3 to 67.6 cm, and belowground biomass ranged from 3 to 576 kg. West. J. Appl. For. 16(1):18–21. Root biomass, ponderosa pine, regression models, environmental management, forest, forest management, forest resources, forestry, forestry research, forestry science, natural resources, natural resource management This content is only available as a PDF. © 2001 by the Society of American Foresters

Omdal, Daniel, W.;Shaw, Charles, G.;Jacobi, William, R.

doi: 10.1093/wjaf/16.1.22pmid: N/A

Abstract Many root disease fungi survive as saprophytes in large roots and stumps, which is the primary means by which they persist on a site from one rotation to the next. A Vibro-Driver/Extractor (VDE) or backhoe excavator was used to remove root systems of 89 ponderosa pine infested with Armillaria ostoyae, and a bulldozer was used to remove root systems of 40 white fir infested with A. ostoyae, Heterobasidion annosum, or both. Based on direct measurements of extracted biomass and models to predict biomass remaining in the soil, all machines removed at least 83% of the belowground coarse root biomass. The VDE was the most powerful machine and was able to extract the largest stumps. The backhoe excavator was used on the smallest stumps, yet left the highest proportion of large root biomass in the ground. Residual biomass following excavations should not be a significant source of root disease fungi as 90% of broken roots were less than 5 cm dia. and would likely decay rapidly. West. J. Appl. For. 16(1):22–25. Armillaria root disease, Heterobasidion annosum, stump removal, ponderosa pine, white fir, environmental management, forest, forest management, forest resources, forestry, forestry research, forestry science, natural resources, natural resource management This content is only available as a PDF. © 2001 by the Society of American Foresters

Thomas,, K.D.;Reid,, W.J.;Comeau,, P.G.

doi: 10.1093/wjaf/16.1.26pmid: N/A

Abstract This study was initiated in 1995 to gather information on the effectiveness of opaque polyethylene mats and glyphosate herbicide treatment on growth and yield of hybrid poplar plantations on south coastal British Columbia. Immediately after planting 40 cm tall hybrid poplar cuttings, 60 × 60 cm opaque polyethylene mats were installed. All treatment plots were mechanically cultivated in one direction twice yearly from 1995 to 1997. This practice left an uncultivated strip between trees running in the same direction as the cultivation. The uncultivated strip was approximately 1 m wide, and represented approximately one-third (0.04 ha) of the total plot area (0.13 ha). Glyphosate was applied at a rate of 2.1 kg active ingredient (ai)/ha in water to the uncultivated strips in the herbicide treatment plots in midsummer of the second and third growing seasons. The opaque polyethylene mats significantly improved poplar height growth only for the first growing season. After four growing seasons, hybrid poplars treated with glyphosate were significantly taller (983 cm) than those in either the mat (915 cm) or control treated plots (902 cm). Diameter at breast height (dbh) was also significantly greater in the herbicide treated plots (88 mm) than in either the mat (78 mm) or control (77 mm) treated plots. Total volume was also significantly greater in herbicide plots (23 ³/ha) than in either the mat (17 m³/ha) or control (17 m³/ha) plots. Basal area and total volume were 14% and 37%, respectively, greater in the herbicide plots than in the mat and control plots following the fourth growing season. West. J. Appl. For. 16(1):26–30. Hybrid poplar, polyethylene mulch mats, glyphosate herbicide, environmental management, forest, forest management, forest resources, forestry, forestry research, forestry science, natural resources, natural resource management This content is only available as a PDF. © 2001 by the Society of American Foresters

Kastner, Walter, W.;Dutton, Steve, M.;Roché, David, M.

doi: 10.1093/wjaf/16.1.31pmid: N/A

Abstract Douglas-fir (Pseudotsuga menziesii var. menziesii) seedlings grown from three seed sources were evaluated for 5 yr on a high-disease-hazard site for their relative tolerance to Swiss needle cast. The seed sources were: (1) seed collected from trees showing an apparent degree of tolerance to Swiss needle cast in natural stands in the coastal fog belt, (2) open-pollinated seed orchard seed collected from random single-pair crosses of parent trees in natural stands outside of the coastal fog belt, but west of the Oregon Coast Range summit, whose progeny demonstrated an apparent degree of disease tolerance in coastal Douglas-fir progeny test sites, and (3) standard reforestation seed purchased from a commercial vendor. There were no significant differences among seed sources in basal diameter and total height for all five growing seasons. Needle retention varied among seed sources over the 5 yr period, but current-year needle retention did not vary significantly after the fifth growing season, and retention of 1- and 2-yr-old needles was relatively low for all seed sources. The intense disease pressure on this site may have overwhelmed expression of disease tolerance among seed sources. We do not recommend planting Douglas-fir on such high-hazard sites. West J. Appl. For. 16(1):31–34. Phaeocryptopus gaeumannii, Pseudotsuga menziesii var. menziesii, Douglas-fir, Oregon, environmental management, forest, forest management, forest resources, forestry, forestry research, forestry science, natural resources, natural resource management This content is only available as a PDF. © 2001 by the Society of American Foresters

Miller,, Mark;Emmingham,, Bill

doi: 10.1093/wjaf/16.1.35pmid: N/A

Abstract Uneven-age management of Douglas-fir (Pseudotsuga menziesii) stands can be used to address aesthetic, wildlife habitat, biodiversity, and sustainability concerns, but there has been little long-term experience with this type of management. To develop timely information on converting even-age stands to uneven-age forests, we used retrospective stand reconstruction methods to document harvest frequency, intensity, and stand structural development at four sites in western Oregon. We studied stands managed by selection thinning and identified strategies for creating and managing uneven-age forests. Selection thinning benefited mid- and understory trees and stimulated natural regeneration. Although stand growth was less than expected from low thinning, growth per unit of growing stock was similar to that in unmanaged stands. Douglas-fir often dominated regeneration and had satisfactory vigor at stocking levels about half that considered full stocking for even-age management, but good growth of regeneration may require even lower overstory stocking. Shade-tolerant grand fir and western hemlock, however, were more abundant at higher stocking levels. Selection thinning of young Douglas-fir stands can sometimes be effective in promoting viable regeneration while providing regular income and biodiversity. Because this was a retrospective study only, further, long-term testing is necessary. West. J. Appl. For. 16(1):35–43. Pseudotsuga menziesii, uneven-age management, Douglas-fir, environmental management, forest, forest management, forest resources, forestry, forestry research, forestry science, natural resources, natural resource management This content is only available as a PDF. © 2001 by the Society of American Foresters