Impact du drainage forestier après coupe sur la croissance de l'épinette noire en forêt boréale

2002 ◽  
Vol 32 (9) ◽  
pp. 1585-1596 ◽  
Author(s):  
Sylvain Jutras ◽  
Jean Bégin ◽  
André P Plamondon

The objective of this study was to retrospectively evaluate, with the help of stem analysis, the growth increases of natural and planted black spruce (Picea mariana (Mill.) BSP) seedlings in 39 drainage networks located in Quebec public boreal forest and drained operationally after cutting. The ecological conditions of the sites have been described using the forest ecosystem classification for the Clay Belt of eastern Ontario. A significant effect of the drainage on 9-year periodic growth in diameter and height of natural black spruce seedlings, varying with distance from the ditch and ecological conditions, was observed. Stocking of natural black spruce seedlings was sufficient to insure the reconstruction of a forest stand both on the treated sites and on the control sites. The 5-year height growth increment of planted black spruce seedlings was weaker than that of the natural seedlings, which were located on the same sites, and it varied with distance from the ditches.

1978 ◽  
Vol 54 (6) ◽  
pp. 296-297 ◽  
Author(s):  
Douglas A. Mead

Height growth of eastern larch (Larix laricina (Du Roi) K. Koch) and black spruce (Picea mariana (Mill.) B.S.P.) was determined using standard stem analysis methods on trees from two sites in northwestern Ontario. The data were obtained from mixed larch-spruce stands which were relatively undisturbed. The larch exhibited substantially better height growth than the spruce through age 65.


1994 ◽  
Vol 24 (8) ◽  
pp. 1629-1635 ◽  
Author(s):  
Robert Jobidon

Light threshold is suggested as a method for quantifying brush competition in black spruce (Piceamariana (Mill.) B.S.P) plantations and predicting losses in tree growth as measured by the relative growth rate (RGR). The severity of the competing vegetation (expressed in terms of density and height) around 300 planted tree seedlings, and the growth status of the seedlings (expressed in terms of total height and current height growth increment), were analyzed simultaneously with multivariate analysis of variance (MANOVA), with one level of light quantity (photosynthetically active radiation) reaching the upper one-half of the tree seedlings as the predictor variable. This study showed that it is possible to establish a competitive status based on light interception, thus allowing a grouping of seedlings with similar growth characteristics and severity of competition. Canonical analysis showed that 60% of full sunlight reaching the upper one half of spruce seedlings can be defined as a threshold to significantly discriminate between stressed and unstressed tree seedlings, based on the above-mentioned variables and also based on spruce basal stem diameter. For spruce total height, current height increment, and basal stem diameter, significant differences were found between plots above and below this threshold, averaging 18.5, 44.7, and 23.2%, respectively. Measuring the intensity of light reaching the upper one half of the spruce seedlings also significantly explains spruce relative growth rates, expressed in terms of height growth increment and basal stem diameter growth increment over the following two growing seasons. The light threshold used in the MANOVA and the ANOVA showed significant differences between plots above and below the threshold, averaging 70 and 58% for spruce height and basal stem diameter RGRs, respectively. Instead of measuring competing vegetation variables and relative height of a crop species to infer light interception, this study demonstrated that a direct measure of light attenuation at the tree seedling level can be used to assess the competitive status and predict losses in tree growth for the period of time required by the seedlings to emerge from the vegetation cover. Moreover, this study demonstrated that canonical relations, rather than linear relations, explain the pattern of competition for light between young spruce seedlings and brushlike vegetation. The light threshold suggested in this study has potential for assessing interspecific competition problems in young black spruce plantations and is proposed as a tool to support a containment strategy of vegetation management.


1983 ◽  
Vol 59 (4) ◽  
pp. 189-191 ◽  
Author(s):  
A. A. Alm

Black spruce (Picea mariana (Mill.) B.S.P.) and white spruce (Picea glauca (Moench) Voss) styrob-lock and paperpot and 3-0 and 2-2 seedlings were planted spring and fall. After four seasons of growth the container seedlings had survival and height growth as good or better than the nursery seedlings. There were no differences in performance between the two container systems. The 2-2 stock generally had better survival than the 3-0 stock. Survival of fall-planted stock was equal to or better than that of the spring-planted stock. Key words: white spruce, black spruce, styroplugs, paper pots, seedlings, transplants, artificial regeneration, fall vs spring planting


1991 ◽  
Vol 21 (4) ◽  
pp. 489-497 ◽  
Author(s):  
Robert Jobidon

Bialaphos foliar sprays were tested in eastern Quebec for control of red raspberry (Rubusidaeus L.), and the tolerance of planted black spruce (Piceamariana (Mill.) B.S.P.) seedlings was determined. Approximately 3 weeks after bialaphos was applied in July, August, or September, virtually all raspberry plants were killed. Efficiency of the June application, however, was much reduced. Spruce current-year foliage was more affected than older foliage. Foliar injury was more pronounced for bialaphos applications in June and July than for applications in August. First-year spruce survival was not affected by the treatments. Second-year evaluations revealed a significant quadratic relation of (i) month of application × bialaphos rate on raspberry density and (ii) bialaphos rate on raspberry height growth. Reduction in raspberry density and height growth was greater with the 2.0 and 2.5 kg active ingredient per hectare rates applied in August. As part of the evaluation of treatment efficiency, photosynthetically active radiation reaching spruce seedlings was measured using a portable integrating radiometer. Raspberry density and height growth were both negatively correlated with photosynthetically active radiation reaching spruce seedlings. A significant quadratic relation was found between bialaphos rate and 2nd-year spruce survival, which reached 95%, regardless of month and rate of application. A significant quadratic relation was found between spruce diameter growth increment and bialaphos rate. Except for calcium, 2nd-year spruce foliar mineral content was not affected by the treatments. Bialaphos treatments in August, with rates ranging from 1.0 to 2.0 kg active ingredient per hectare, had only slight or no adverse effects on spruce survival, foliar injury, and growth increment. Selective control of red raspberry in young black spruce plantations is a function of bialaphos rate and month of application.


1999 ◽  
Vol 29 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Raynald Paquin ◽  
Hank A Margolis ◽  
René Doucet ◽  
Marie R Coyea

Growth and physiology of layers versus naturally established seedlings of boreal black spruce (Picea mariana (Mill.) BSP) were compared 15 years after a cutover in Quebec. During the first 8 years, height growth of seedlings was greater than that of layers, averaging 10.4 and 7.0 cm/year, respectively. For the last 5 years, annual height growth of layers and seedlings did not differ (25 cm/year; p > 0.05). Over the entire 15-year period, total height growth of seedlings (251 cm) was greater than that of layers (220 cm), although total height did not differ (p > 0.05) over the last 6 years. During the 15th growing season, there were no differences (p > 0.05) for predawn shoot water potential, stomatal conductance, net photosynthesis, intercellular to ambient CO2 ratio, water use efficiency, and hydraulic conductance between layers and seedlings. For diurnal shoot water potential, seedlings showed slightly less stress than layers on two of the four sampling dates. Thus, in the first few years following the cutover, the slower growth observed for layers indicated that they had a longer acclimation period following the cutover. Afterwards, similar height growth, total height, and physiological characteristics of the two regeneration types indicated that layers can perform as well as naturally established seedlings.


1975 ◽  
Vol 51 (2) ◽  
pp. 53-54
Author(s):  
W. Stanek

Black spruce (Picea mariana [Mill.] B.S.P.) and jack pine (Pinus banksiana Lamb.) seedlings were grown in a green-house on peat-filled flats flooded with nutrient solution or distilled water. None was aerated. However, an O2 concentration gradient existed across the flats, 3.0 – 3.7 ppm along the edges, and 1.4 – 1.9 ppm in the centers. After 4½ months seedlings of both species grew taller with nutrient solution than with distilled water. In flats supplied with nutrient solution, seedlings of both species grew taller along the edges than in the centers, whereas in flats supplied with distilled water height differential did not develop. Jack pine grew taller than black spruce under similar conditions.


2000 ◽  
Vol 30 (1) ◽  
pp. 59-66 ◽  
Author(s):  
David Pothier

Regeneration of first-cut strips in a two-cut system of strip clear-cutting was compared to that of large clear-cutting in four different areas representative of the black spruce (Picea mariana (Mill.) BSP) stands of the boreal forest of Quebec. Seedlings were more evenly distributed in clearcut strips than in large clearcuts. Differences of about 10 000 black spruce seedlings per hectare and 20% of stocking were observed in favour of clearcut strips compared to large clearcuts. Black spruce stocking was about 14% larger on lowland than on upland sites but height growth was better on upland sites. A regeneration problem similar to that of large clearcuts was observed when the second strips were cut. One year after cutting these second strips, winter harvesting resulted in a 23% gain in black spruce stocking as compared to summer harvesting. Even if black spruce stocking marginally increased during the years following winter harvesting, the height advantage of the preserved advance growth justifies the application of this harvesting method. The strip clear-cutting system effectively improved the stocking of former black spruce stands but if the stocking level of advance growth is adequate, careful harvesting to preserve advance regeneration should be the preferred method since it would be more cost-efficient.


2003 ◽  
Vol 33 (11) ◽  
pp. 2097-2107 ◽  
Author(s):  
Marcel Prévost ◽  
Daniel Dumais

Careful logging around advance growth (CLAAG) and tree planting following site preparation or not (fill planting) are widely used to regenerate black spruce (Picea mariana (Mill.) BSP) stands in the boreal forest of Quebec, Canada. However, few mid-term studies have compared these different regeneration modes. In this study, we examined height growth and nutrient status of black spruce layers, natural seedlings, and planted seedlings over a 10-year period, in an experimental design combining CLAAG, natural seeding, planting, and two types of scarification (cones and disks). Without scarification, growth of planted seedlings (5.8 cm·year–1) was slightly greater than that of layers (4.4 cm·year–1) and natural seedlings (4.1 cm·year–1). Scarification improved growth of the three types of regeneration, but the treatment was more beneficial for planted seedlings (+7.1 cm·year–1) than for natural seedlings (+1.6 cm·year–1) and layers (+1,0 cm·year–1). Five years after treatment, scarification had increased the current-year needle N concentration of the three types of regeneration, but this beneficial effect on N was still detectable only in foliage of layers after 10 years. The effect of the treatment was variable for P and K contents, for which natural regeneration seems to have taken advantage more than plants. Our results indicate that scarification can improve the initial growth and nutrient status of both natural and artificial regeneration of black spruce and thus accelerate site recovery after cutting in the boreal forest. Furthermore, fill planting without site preparation appeared to be clearly less efficient than planting combined with scarification.


2000 ◽  
Vol 30 (4) ◽  
pp. 573-579 ◽  
Author(s):  
G G Wang ◽  
J Su ◽  
J R Wang

Four simple measures of interspecific competition (percent cover visually estimated in the field, percent cover derived from hemispherical photographs, percent full sunlight measured by a ceptometer, and gap light index derived from hemispherical photographs) obtained at two reference positions (the top and the middle of crop seedlings) were evaluated in relation to two growth variables (relative height growth rates in 1998 and during 1996 to 1998) of black spruce (Picea mariana (Mill.) BSP) seedlings planted on boreal mixedwood sites in southeastern Manitoba. The four competition measures assessed at the two measuring positions explained 57.2-68.0% of the total variation in black spruce height growth rate. Significant relationships were found among the four measures, and between the two measuring positions for each measure. The measuring position was not critical for all competition measures except the percent full sunlight measured by the ceptometer, for which the middle position was much better. When assessed at their preferred positions, the four competition measures ranked as follows: (i) percent cover derived from hemispherical photographs or percent full sunlight measured by the ceptometer; (ii) gap light index derived from hemispherical photographs; and (iii) visually estimated percent cover of vegetation.


2002 ◽  
Vol 78 (2) ◽  
pp. 306-313 ◽  
Author(s):  
Gordon D Nigh ◽  
Pavel V Krestov ◽  
Karel Klinka

Black spruce (Picea mariana (Mill.) B.S.P.) is a boreal species that occurs extensively across the northern half of British Columbia. Forest managers require better growth and yield information for black spruce given the anticipated increase in demand for wood in the northern part of the province. The purpose of this study was to develop height-age models for black spruce. Ninety-one stem analysis plots were established in the BWBS and SBS biogeoclimatic zones. Three black spruce site trees from each plot were stem analyzed and the data were converted into height-age data. A conditioned log-logistic function was fit to the data. Indicator variables were used to test for differences in height growth between the sampled subzones. Although the warm subzones had different height growth patterns than the cool subzones, there was general agreement among the height-age models from British Columbia, Alberta, and New Brunswick up to about age 100. Key words: biogeoclimatic zones, height-age models, logistic function, site index, stem analysis


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