Winter use of montane forests by porcupines in southwestern Alberta: preferences, density effects, and temporal changes

1980 ◽  
Vol 58 (1) ◽  
pp. 13-19 ◽  
Author(s):  
Lawrence D. Harder

The pattern of winter use of montane forest by porcupines (Erethizon dorsatum) during a 40-year period was examined on two areas in southwestern Alberta. Of the three available coniferous communities, porcupines fed in relatively more trees in pure stands of Douglas fir (Pseudotsuga menziesii) in leeward situations. Douglas fir, limber pine (Pinus flexilis), and hybrid spruce (Picea glauca × P. engelmannii) were used with equivalent frequency when found in the same community. The number of porcupines that used both areas peaked and declined in relation to the average ages of the forests. Trees in low density stands (< 11 trees/100 m2) were fed in during more years than those in denser stands and the use of dense stands was more frequent during years when porcupines were most abundant. Differences between the study areas in repeated feeding in leeward Douglas fir and in the relative proportions of trees used in low and high density stands are attributed to differences in the abundance of porcupines.

1981 ◽  
Vol 113 (4) ◽  
pp. 337-340 ◽  
Author(s):  
W. W. Nijholt ◽  
L. H. McMullen ◽  
L. Safranyik

AbstractPine oil, a by-product of sulphate wood pulping, protected pheromone-baited, living Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), lodgepole pine (Pinus contorta Dougl.), and spruce (Picea glauca (Moench) Voss - P. engelmannii Parry hybrids) from attack by Douglas-fir beetle (Dendroctonus pseudotsugae Hopk.), mountain pine beetle (D. ponderosa Hopk.), and spruce beetle (D. rufipennis (Kirby)), respectively. Pine oil also protected surrounding trees and reduced attack incidence on Douglas-fir, lodgepole pine, and spruce within at least a 10 m radius. α-Terpineol, one of the constituents of the pine oil mixture, was less effective.


1987 ◽  
Vol 27 (3) ◽  
pp. 323-331 ◽  
Author(s):  
Jim I. Mead ◽  
Larry D. Agenbroad ◽  
Arthur M. Phillips ◽  
Larry T. Middleton

AbstractThe extinct Harrington's mountain goat (Oreamnos harringtoni Stock) is predominantly known from dry cave localities in the Grand Canyon, Arizona, in addition to two sites in the Great Basin, Nevada, and from San Josecito Cave, Nuevo Leon, Mexico. A dry shelter in Natural Bridges National Monument, on the central Colorado Plateau, southeastern Utah, preserves numerous remains of the extinct mountain goat in addition to pack rat middens. Remains from a 100-cm stratigraphic profile indicate that O. harringtoni lived on the plateau >39,800 yr B.P., the oldest directly dated find of extinct mountain goat. Plant macrofossils indicate that Engelmann's spruce (Picea engelmannii), limber pine (Pinus flexilis), rose (Rosa cf. woodsii), and Douglas fir (Pseudotsuga menziesii) grew during the late Pleistocene where a riparian and a pinyon-juniper (Pinus edulis-Juniperus osteosperma) community now predominates; Douglas fir are found only in mesic, protected, north-facing areas. Limber pine, Douglas fir, bark, and grasses were the major dietary components in the dung. A springtime diet of birch (Betula) is determined from pollen clumps in dung pellets.


1982 ◽  
Vol 62 (3) ◽  
pp. 703-707 ◽  
Author(s):  
W. C. LIN ◽  
J. M. MOLNAR

Daily 16-h (0400–2000 h) supplementary lighting with high-pressure sodium (HPS) lamps at 45 μE∙m2∙sec−1 increased growth of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), white spruce (Picea glauca (Moench) Voss), crape-myrtle (Lagerstroemia indica L.), and seven cultivars of English holly (Ilex aquifolium L.). Enrichment of greenhouse atmosphere with CO2 to 1000–1300 ppm increased growth of four cultivars of English holly. In comparing two different light sources in CO2-enriched greenhouses, low-pressure sodium (LPS) lamps at 42 μE∙m−2∙sec−1 were found as effective as HPS in increasing growth of white spruce, crape-myrtle, and five cultivars of English holly, but not so effective in Douglas-fir and three cultivars of English holly.


1959 ◽  
Vol 91 (10) ◽  
pp. 601-617 ◽  
Author(s):  
Margaret E. P. Gumming

Adelges cooleyi (Gill.) causes galls on spruce in the forests and on shelter-belt and shade-tree plantings in Alberta. The alternate host is Douglas fir, on which the injury is less conspicuous. The tree species affected are white spruce, Picea glauca (Moench) Voss, Engelmann spruce, P. engelmanni Parry, and blue Douglas fir, Pseudotsuga menziesii (Mirb.) Franco. A. cooleyi is indigenous to North America.


1999 ◽  
Vol 131 (5) ◽  
pp. 635-643 ◽  
Author(s):  
Björn G. Prenzel ◽  
William G. Laidlaw ◽  
Hal Wieser

AbstractThe within-tree scale dynamics of mass attack by the Douglas-fir beetle, Dendroctonus pseudotsugae Hopkins, on its host were investigated and quantified. Seven similarly sized Douglas-fir, Pseudotsuga menziesii (Mirb.) Franco (Pinaceae), infested as part of several pheromone-induced infestations, were monitored over an entire attack season. Ninety percent of the attacks on mass-attacked trees occurred within 3 weeks of colonization; the remaining 10% occurred gradually over the remaining 7 weeks of the attack season. Vertical attack distribution followed a Gaussian form that shifted upwards on the bole with increasing attack density. The change in attack pattern associated with increasing attack density was investigated for the central vertical portion of the bole, where most attacks occurred, and where the vertical pattern was least variable. At low density, attacks were randomly distributed. As density increased, the distance between attacks decreased, eventually resulting in a uniform distribution.


Plant Disease ◽  
2013 ◽  
Vol 97 (6) ◽  
pp. 744-748 ◽  
Author(s):  
Jerry E. Weiland ◽  
Bryan R. Beck ◽  
Anne Davis

Pythium species are common soilborne oomycetes that occur in forest nursery soils throughout the United States. Numerous species have been described from nursery soils. However, with the exception of P. aphanidermatum, P. irregulare, P. sylvaticum, and P. ultimum, little is known about the potential for other Pythium species found in nursery soils to cause damping-off of tree seedlings. A greenhouse study was conducted to evaluate the pathogenicity and virulence of 44 Pythium isolates representing 16 species that were originally recovered from soil at three forest nurseries in Washington and Oregon. Seeds of Douglas-fir (Pseudotsuga menziesii) were planted into soil infested with each of the isolates. Seedling survival, the number of surviving seedlings with necrotic root lesions, and taproot length were evaluated 4 weeks later. Responses of Douglas-fir to inoculation varied significantly depending on Pythium species and isolate. Eight species (P. dissotocum, P. irregulare, P. aff. macrosporum, P. mamillatum, P. aff. oopapillum, P. rostratifingens, P. sylvaticum, and P. ultimum var. ultimum) significantly reduced the number of surviving seedlings compared to the noninoculated treatment. However, all Pythium species caused a greater percentage of seedlings to develop root lesions (total mean 40%) than was observed from noninoculated seedlings (17%). Taproot length varied little among Pythium treatments and was not a useful character for evaluating pathogenicity. Results confirm the ability of P. irregulare, P. mamillatum, and P. ultimum var. ultimum to cause damping-off of Douglas-fir seedlings, and are indicative that other species such as P. dissotocum, P. aff. macrosporum, P. aff. oopapillum, P. rostratifingens, and P. sylvaticum may also be responsible for seedling loss.


1998 ◽  
Vol 28 (8) ◽  
pp. 1198-1206 ◽  
Author(s):  
Paige E Axelrood ◽  
William K Chapman ◽  
Keith A Seifert ◽  
David B Trotter ◽  
Gwen Shrimpton

Poor performance of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) plantations established in 1987 has occurred in southwestern British Columbia. Affected sites were planted with 1-year-old container stock that exhibited some root dieback in the nursery. A study was initiated in 1991 to assess Cylindrocarpon and Fusarium root infection in planted and naturally regenerating (natural) Douglas-fir seedlings from seven affected plantations. Percentages of seedlings harboring Cylindrocarpon spp.and percent root colonization were significantly greater for planted seedlings compared with natural seedlings. A significant linear trend in Cylindrocarpon root colonization was observed for planted seedlings with colonization levels being highest for roots closest to the remnants of the root plug and decreasing at distances greater than 10cm from that region. This trend in Cylindrocarpon colonization was not observed for natural seedlings. Cylindrocarpon destructans (Zins.) Scholten var. destructans and C.cylindroides Wollenw. var. cylindroides were the only species isolated from planted and natural conifer seedlings. For most sites, percentage of seedlings harboring Fusarium spp.and percent Fusarium root colonization were less than for Cylindrocarpon. Recovery of Fusarium spp.from seedlings and root colonization levels were not significantly different for planted and natural seedlings from all sites.


Author(s):  

Abstract A new distribution map is provided for Contarinia pseudotsugae Condrashoff (Diptera: Cecidomyiidae). Hosts: Douglas fir (Pseudotsuga menziesii). Information is given on the geographical distribution in Europe (Belgium, France, Germany and Netherlands) and North America (Canada, British Columbia, USA, California, Idaho, Michigan, Montana, Oregon, Pennsylvania and Washington).


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