scholarly journals Tryblidiopsis magnesii sp. nov. from Picea glauca in Eastern Canada

Author(s):  
J.B. Tanney ◽  
K.A. Seifert
Keyword(s):  
1967 ◽  
Vol 45 (9) ◽  
pp. 1703-1714 ◽  
Author(s):  
E. Von Rudloff

The leaf oils from white and black spruce obtained from different locations in Western and Eastern Canada, Michigan, and Minnesota, have been analyzed by gas liquid chromatography. Both species were found to have a remarkably consistent and distinctive distribution pattern of the leaf oil terpenes. The quantitative variations encountered in samples of the same species from different populations are relatively small and ecological differences are not found to affect the leaf oil composition. Hence, analysis of spruce leaf oils appears to be highly suitable for a study of introgression and hybridization.


1981 ◽  
Vol 57 (6) ◽  
pp. 273-275 ◽  
Author(s):  
J. R. Blais

The history of spruce bubworm (Choristoneura fumiferana (Clem.)) outbreaks for the past two hundred years in the Ottawa River Valley in Quebec was retraced through radial-growth studies on old white spruce (Picea glauca (Moench)) and black spruce (Picea mariana (Mill.) B.S.P.) trees. The radial-growth profiles clearly indicate three suppression periods resulting from outbreaks that occurred in the twentieth century, each starting about 1910, 1940 and 1967. There is no evidence of an outbreak during the nineteenth century in this region. However, a reduction in radial-growth starting in 1783 observed on the only three specimens of white spruce over 200 years old, has the characteristics of that caused by a budworm outbreak. An interval of 127 years between this and the 1910 outbreak is similar to other long intervals between outbreaks recorded prior to the twentieth century for some other regions in eastern Canada.


2020 ◽  
Vol 118 (5) ◽  
pp. 515-533
Author(s):  
Laurie Dupont-Leduc ◽  
Robert Schneider ◽  
Luc Sirois

Abstract In 2008, a thinning trial consisting in the removal of competitors around high growth potential stems (crop trees, CTs) was initiated as the first step of a structural conversion to transform even-aged stands into uneven-aged stands. Two intensities of thinning by CT release and thinning from below were tested in white spruce (Picea glauca [Moench] Voss) plantations and in balsam fir (Abies balsamea [L.] Mill)—dominated naturally regenerated stands. Unlike thinning from below, which aims to remove poor quality stems to improve the growth of residual trees, thinning by CT release aims to reduce competition between dominant trees. Trees thinned by CT release showed a significantly higher diameter at breast height increment than those in the control plots. CT release did not significantly increase stand structure, nor did it reduce stand growth, which helps to address the concerns of regional forest stakeholders. CT release may offer other benefits in the long term, but subsequent interventions are necessary to evaluate if this treatment meets the desired objectives.


2019 ◽  
Vol 8 (23) ◽  
Author(s):  
Diana Lin ◽  
Lauren Coombe ◽  
Shaun D. Jackman ◽  
Kristina K. Gagalova ◽  
René L. Warren ◽  
...  

Here, we present the complete chloroplast genome sequence of white spruce (Picea glauca, genotype WS77111), a coniferous tree widespread in the boreal forests of North America. This sequence contributes to genomic and phylogenetic analyses of the Picea genus that are part of ongoing research to understand their adaptation to environmental stress.


1956 ◽  
Vol 34 (4) ◽  
pp. 523-561 ◽  
Author(s):  
J. C. Ritchie

It is pointed out that there are available no ecological accounts of the vegetation of Northern Manitoba and the surrounding regions. After brief accounts of the topography, geology, and climate, the communities which were met with in two areas of study are described. It is shown that the predominant and stable forest of mesic sites is dominated by Picea mariana, with a ground vegetation composed chiefly of weft-form mosses. In areas which have been burned various subseral variants of this forest are present. Pinus banksiana, as well as being a seral dominant of mesic sites, dominates various forests of outcrop ridges, sand plains, and eskers. Picea glauca is rare in the area, occurring only on those sites which show exceptionally favourable conditions of habitat. The vegetation of this region conforms with descriptions of the Southern Spruce Forest Zone of Eastern Canada, which classification might well be extended westwards at least as far as northwest Manitoba. There is some evidence that the dry climate which prevails west of the region, and for which there is slight evidence here, has influenced the flora and vegetation of the region. A description is given of a highly local community of Betula papyrifera var. neoalaskana on organic ridges which appears never to have been recorded previously for North America.


2013 ◽  
Vol 89 (03) ◽  
pp. 392-400 ◽  
Author(s):  
François Hébert ◽  
Vincent Roy ◽  
Isabelle Auger ◽  
Martin-Michel Gauthier

The use of gap-based silviculture and enrichment planting was tested in temperate mixedwood forests in eastern Canada. Four different sizes of canopy opening or patch cuts were applied to six stands in the maple–birch domain of Quebec. We evaluated the influence of opening size, cardinal quadrant within the opening, and distance from the forest edge of openings on white spruce height and ground-level diameter (GLD) five years after enrichment planting. At ≥5 m from the edge, initial canopy transmittance was generally >60% in all four canopy treatments. White spruce seedling height and GLD were lower within 10 m from the edge, and generally increased where understory light levels were higher. Seedling survival, height, and GLD in the smallest opening (0.05 ha) were comparable or higher than those found in relatively larger openings. The 0.05-ha opening that more closely emulates natural canopy gaps of temperate mixedwood forests provided satisfactory seedling development, and is therefore compatible with a gap-based stand dynamics approach to management of mixedwood stands in Quebec.


1992 ◽  
Vol 68 (5) ◽  
pp. 614-622 ◽  
Author(s):  
Jean J. Turgeon

The spruce bud moth, Zeiraphera canadensis, represents an economic threat to white spruce, Picea glauca, managed for lumber production in eastern Canada. Larvae feed on developing shoots. Larval feeding on the leader adversely affects tree form and reduces vertical growth. Although the economic impact of this insect has not been critically established, it is feared that this damage could decrease the quality and value of the lumber produced and could delay harvest by several years. This paper reviews the information on the spruce bud moth life cycle, behaviour, impact, sampling and monitoring, and the possible management tactics investigated to date.


2013 ◽  
Vol 145 (4) ◽  
pp. 406-415 ◽  
Author(s):  
K.L. Ryall ◽  
P. Silk ◽  
G.S. Thurston ◽  
T.A. Scarr ◽  
P. de Groot

AbstractFrontalin, seudenol, and a spruce terpene blend are key components of a lure for monitoring spruce beetle, Dendroctonus rufipennis (Kirby) (Coleoptera: Curculionidae: Scolytinae) in eastern Canada, catching the highest number of beetles in several field trials. The standard two-component commercial lure for this species, developed from populations in western North America and composed of 95%:5% (±)-α-pinene and frontalin, failed to elicit attraction to traps in Atlantic Canada; thus a series of trapping experiments were conducted to identify an improved combination of pheromone and host volatiles for this region. Analysis of volatiles from D. rufipennis collected from Newfoundland and Nova Scotia, Canada detected seudenol as an additional female-produced component. Laboratory analysis of the eastern host (Picea glauca (Moench) Voss; Pinaceae) detected the presence of 75%:25% (±)-α-pinene; however, a two-component lure comprised of 75%:25% (±)-α-pinene and frontalin caught no more beetles than an unbaited control. Frontalin and seudenol alone or spruce terpene blend and ethanol alone typically had among the lowest trap catches, but when combined they caught the highest numbers of D. rufipennis, supporting the hypothesis that host volatiles synergise attraction to pheromones. Our results highlight the importance of geographic variation in the response to pheromones and kairomones in this bark beetle.


2016 ◽  
Vol 46 (10) ◽  
pp. 1205-1215 ◽  
Author(s):  
Jessica Smith ◽  
Brian D. Harvey ◽  
Ahmed Koubaa ◽  
Suzanne Brais ◽  
Marc J. Mazerolle

Mixed-species stands present a number of opportunities for and challenges to forest managers. Boreal mixedwood stands in eastern Canada are often characterized by a dominant canopy of shade-intolerant aspen (Populus tremuloides Michx.) with more shade-tolerant conifers in the mid- to sub-canopy layers. Because the aspen and conifer components often attain optimal merchantable sizes at different moments in stand development, there is an interest in developing silvicultural practices that allow partial or total removal of aspen and favour accelerated growth of residual conifers. We tested four partial harvesting treatments in mixed aspen – white spruce (Picea glauca (Moench.) Voss) stands in which different proportions of aspen (0%, 50%, 65%, and 100% basal area) were removed. Ten years after treatments, 72 spruce stems representing dominant, co-dominant, and suppressed social classes were destructively sampled for stem analysis. Using linear mixed effect models, we analyzed growth as a function of treatment intensity, time since treatment, social status, pretreatment growth rate, and neighbourhood competition. Relative to control stands, radial and volume growth responses were detected only in the extreme treatment of 100% aspen removal. In relative terms, suppressed trees showed the greatest magnitude of cumulative growth increase. Compared with control trees, average annual radial and volume increments were, respectively, 23.5% and 7.1% higher for dominant trees, 67.7% and 24.1% higher for co-dominant trees, and 115.8% and 65.6% higher for suppressed trees over the 10 years after treatment. Growth response was proportional to pretreatment growth rate, and among neighbouring trees, only coniferous neighbours had a negative effect on white spruce growth. Our results suggest that in similar mixed-stand conditions, relatively heavy removal of overstory aspen accompanied by thinning of crowded conifers would result in greatest growth response of residual spruce stems.


2005 ◽  
Vol 35 (1) ◽  
pp. 1-12 ◽  
Author(s):  
Kenneth J Stadt ◽  
Victor J Lieffers ◽  
Ronald J Hall ◽  
Christian Messier

To investigate the feasibility of a spatially explicit, radiation-based regeneration model for the boreal forest, we tested the predictions of a three-dimensional simulator of photosynthetically active radiation transmission (%PAR), MIXLIGHT, and the growth response of understory Abies balsamea (L.) Mill. (balsam fir) and Picea glauca (Moench) Voss (white spruce) to %PAR in two large (>1 ha) mixed-species forest sites, one in eastern Canada at Lac Duparquet, Quebec, and one in western Canada at Calling Lake, Alberta. Overstory tree locations and dimensions were obtained from aerial photographs or ground measurements and allometric relationships. Seasonal %PAR calculated by MIXLIGHT for the Calling Lake site was very similar to seasonal %PAR measured by quantum sensors (n = 5, %PAR range = 15%–33%, r = 0.93). Daily measurements of %PAR were also predicted well by simulations at both sites (n = 34–36, %PAR range = 1%–45%, r ≥ 0.76). Functional relationships, designed to saturate at the maximum height growth potential of these sites, were developed to predict sapling height growth from simulated seasonal %PAR and initial height (R2 ≥ 0.74). These results demonstrate the potential of the MIXLIGHT simulator for estimating PAR at microsites within heterogeneous forests and for modeling understory tree growth.


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