Developmental Trends of Black Spruce Fibre Attributes in Maturing Plantations

This study assessed the temporal developmental patterns of commercially relevant fibre attributes (tracheid length and diameters, wall thickness, specific surface area, wood density, microfibril angle, fibre coarseness, and modulus of elasticity) and their interrelationships within maturing black spruce (Picea mariana (Mill.) B.S.P.) plantations. A size-based stratified random sample procedure within 5 semimature plantations located in the Canadian Boreal Forest Region was used to select 50 trees from which radial cross-sectional xylem sequences at breast-height (1.3 m) were cut and analyzed. Statistically, the graphical and linear correlation analyses indicated that the attributes exhibited significant (p≤0.05) relationships among themselves and with morphological tree characteristics. Relative variation of each annually measured attribute declined with increasing size class (basal area quintile). The transitional shifts in temporal correlation patterns occurring at the time of approximate crown closure where suggestive of intrinsic differences in juvenile and mature wood formation processes. The temporal cumulative development patterns of all 8 of the annually measured attributes varied systematically with tree size and exhibited the most rapid rates of change before the trees reached a cambial age of 20 years. At approximately 50 years after establishment, plantation mean attribute values were not dissimilar from those reported for more mature natural-origin stands.

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Root rot damage in naturally regenerated stands of spruce and balsam fir in Ontario

Canadian Journal of Forest Research ◽

10.1139/x89-045 ◽

1989 ◽

Vol 19 (3) ◽

pp. 295-308 ◽

Cited By ~ 27

Author(s):

R. D. Whitney

Keyword(s):

Root Rot ◽

Black Spruce ◽

Basal Area ◽

Ground Level ◽

White Spruce ◽

Balsam Fir ◽

Tree Age ◽

Stand Age ◽

Root Decay ◽

Forest Region

In an 11-year study in northern Ontario, root rot damage was heaviest in balsam fir, intermediate in black spruce, and least in white spruce. As a result of root rot, 16, 11, and 6%, respectively, of dominant or codominant trees of the three species were killed or experienced premature windfall. Butt rot, which resulted from the upward extension of root rot into the boles of living trees, led to a scaled cull of 17, 12, and 10%, respectively, of gross merchantable volume of the remaining living trees in the three species. The total volume of wood lost to rot was, therefore, 33, 23, and 16%, respectively. Of 1108 living dominant and codominant balsam fir, 1243 black spruce, and 501 white spruce in 165 stands, 87, 68, and 63%, respectively, exhibited some degree of advanced root decay. Losses resulting from root rot increased with tree age. Significant amounts of root decay and stain (>30% of root volume) first occurred at 60 years of age in balsam fir and 80 years in black spruce and white spruce. For the three species together, the proportion of trees that were dead and windfallen as a result of root rot increased from an average of 3% at 41–50 years to 13% at 71–80 years and 26% at 101–110 years. The root rot index, based on the number of dead and windfallen trees and estimated loss of merchantable volume, also increased, from an average of 17 at 41–50 years to 40 at 71–80 years and 53 at 101–110 years. Death and windfall of balsam fir and black spruce were more common in northwestern Ontario than in northeastern Ontario. Damage to balsam fir was greater in the Great Lakes–St. Lawrence Forest region than in the Boreal Forest region. In all three tree species, the degree of root rot (decay and stain) was highly correlated with the number of dead and windfallen trees, stand age, and root decay at ground level (as a percentage of basal area) for a 10-tree sample.

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Characterizing compression wood formed in radiata pine branches

IAWA Journal ◽

10.1163/22941932-00000073 ◽

2014 ◽

Vol 35 (4) ◽

pp. 385-394

Author(s):

Xinguo Li ◽

Robert Evans ◽

Washington Gapare ◽

Xiaohui Yang ◽

Harry X. Wu

Keyword(s):

Compression Wood ◽

Microfibril Angle ◽

Marked Change ◽

Radiata Pine ◽

Wood Formation ◽

Reaction Wood ◽

Opposite Wood ◽

Cambial Age ◽

Cellulose Microfibril Orientation ◽

Secondary Wall Formation

The formation of reaction wood is an adaptive feature of trees in response to various mechanical forces. In gymnosperms, reaction wood consists of compression wood (CW) and opposite wood (OW) that are formed on the underside and upperside of bent trunks and branches. Although reaction wood formed in bent trunks has been extensively investigated, relatively little has been reported from conifer branches. In this study SilviScan® technology was used to characterize radiata pine branches at high resolution. Compared to OW formed in the branches, CW showed greater growth, darker colour, thicker tracheid walls, higher coarseness, larger microfibril angle (MFA), higher wood density, lower extensional stiffness and smaller internal specific surface area. However, tracheids of CW were similar to those of OW in their radial and tangential diameters. These results indicated that gravity influenced tracheid cell division and secondary wall formation but had limited impact on primary wall expansion. Furthermore, seasonal patterns of CW formation were not observed in the branches from cambial age 4 while earlywood and latewood were clearly separated in all rings of OW. The marked change of MFA during reaction wood formation suggested that branches could be ideal materials for further study of cellulose microfibril orientation.

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Allometric Equations for Estimating Biomass and Carbon Stocks in Afforested Open Woodlands with Black Spruce and Jack Pine, in the Eastern Canadian Boreal Forest

Forests ◽

10.3390/f12010059 ◽

2021 ◽

Vol 12 (1) ◽

pp. 59

Author(s):

Olivier Fradette ◽

Charles Marty ◽

Pascal Tremblay ◽

Daniel Lord ◽

Jean-François Boucher

Keyword(s):

Large Scale ◽

Ad Hoc ◽

Black Spruce ◽

Tree Height ◽

Jack Pine ◽

Carbon Stocks ◽

Allometric Equations ◽

C Stocks ◽

The Difference ◽

Canadian Boreal Forest

Allometric equations use easily measurable biometric variables to determine the aboveground and belowground biomasses of trees. Equations produced for estimating the biomass within Canadian forests at a large scale have not yet been validated for eastern Canadian boreal open woodlands (OWs), where trees experience particular environmental conditions. In this study, we harvested 167 trees from seven boreal OWs in Quebec, Canada for biomass and allometric measurements. These data show that Canadian national equations accurately predict the whole aboveground biomass for both black spruce and jack pine trees, but underestimated branches biomass, possibly owing to a particular tree morphology in OWs relative to closed-canopy stands. We therefore developed ad hoc allometric equations based on three power models including diameter at breast height (DBH) alone or in combination with tree height (H) as allometric variables. Our results show that although the inclusion of H in the model yields better fits for most tree compartments in both species, the difference is minor and does not markedly affect biomass C stocks at the stand level. Using these newly developed equations, we found that carbon stocks in afforested OWs varied markedly among sites owing to differences in tree growth and species. Nine years after afforestation, jack pine plantations had accumulated about five times more carbon than black spruce plantations (0.14 vs. 0.80 t C·ha−1), highlighting the much larger potential of jack pine for OW afforestation projects in this environment.

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The Difficulty of Predicting Eastern Spruce Dwarf Mistletoe in Lowland Black Spruce: Model Benchmarking in Northern Minnesota, USA

Forests ◽

10.3390/f12070843 ◽

2021 ◽

Vol 12 (7) ◽

pp. 843

Author(s):

Ella R. Gray ◽

Matthew B. Russell ◽

Marcella A. Windmuller-Campione

Keyword(s):

Stand Structure ◽

Black Spruce ◽

Forest Health ◽

Basal Area ◽

Predictive Performance ◽

Stand Age ◽

Management Decisions ◽

Dwarf Mistletoe ◽

Growing Seasons ◽

Model Interpretation

Insects, fungi, and diseases play an important role in forest stand development and subsequently, forest management decisions and treatments. As these disturbance agents commonly occur within and across landscapes, modeling has often been used to inform forest planning and management decisions. However, models are rarely benchmarked, leaving questions about their utility. Here, we assessed the predictive performance of a Bayesian hierarchical model through on–the-ground sampling to explore what features of stand structure or composition may be important factors related to eastern spruce dwarf mistletoe (Arceuthobium pusillum Peck) presence in lowland black spruce (Picea mariana (Mill.) B. S. P.). Twenty-five state-owned stands included in the predictive model were sampled during the 2019 and 2020 growing seasons. Within each stand, data related to the presence of eastern spruce dwarf mistletoe, stand structure, and species composition were collected. The model accurately predicted eastern spruce dwarf mistletoe occurrence for 13 of the 25 stands. The amount of living and dead black spruce basal area differed significantly based on model prediction and observed infestation, but trees per hectare, total living basal area, diameter at breast height, stand age, and species richness were not significantly different. Our results highlight the benefits of model benchmarking to improve model interpretation as well as to inform our understanding of forest health problems across diverse stand conditions.

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Exploring the Recruitment Dynamics of Sugar Maple and Yellow Birch Saplings into Merchantable Stems Following Harvesting in the Acadian Forest Region of New Brunswick, Canada

Canadian Journal of Forest Research ◽

10.1139/cjfr-2021-0226 ◽

2021 ◽

Author(s):

Alex Noel ◽

Jules Comeau ◽

Salah-Eddine El Adlouni ◽

Gaetan Pelletier ◽

Marie-Andrée Giroux

Keyword(s):

New Brunswick ◽

Sugar Maple ◽

Basal Area ◽

Stem Density ◽

Yellow Birch ◽

Probability Of Occurrence ◽

Silvicultural Treatment ◽

Forest Region ◽

Wide Range ◽

Acadian Forest

The recruitment of saplings in forest stands into merchantable stems is a very complex process, thus making it challenging to understand and predict. The recruitment dynamics in the Acadian Forest Region of New Brunswick are not well known or documented. Our objective was to draw an inference from existing large scale routine forest inventories as to the different dynamics behind the recruitment from the sapling layer into the commercial tree size layer in terms of density and occurrence of sugar maple (Acer saccharum Marsh.) and yellow birch (Betula alleghaniensis Britt.) following harvesting, by looking at many factors on a wide range of spatial and temporal scales using models. Results suggest that the variation in density and probability of occurrence is best explained by the intensity of silvicultural treatment, by the merchantable stem density in each plot, and by the proportion of merchantable basal area of each group of species. The number of recruits of sugar maple and yellow birch stems tend be higher when time since last treatment increases, when mid to low levels of silvicultural treatment intensity were implemented, and within plots having intermediate levels of merchantable stem density. Lastly, our modeling efforts suggest that the probability of occurrence and density of recruitment of both species tend to increase while its share of merchantable basal area increases.

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Fungi of the Canadian boreal forest region: Catulus aquilonius gen. et sp.nov., a hyperparasite on Seuratia millardetii

Canadian Journal of Botany ◽

10.1139/b78-284 ◽

1978 ◽

Vol 56 (19) ◽

pp. 2344-2347 ◽

Cited By ~ 2

Author(s):

D. Malloch ◽

C. T. Rogerson

Keyword(s):

Boreal Forest ◽

New Genus ◽

New Genus And Species ◽

Forest Region ◽

Canadian Boreal Forest ◽

Boreal Forest Region

A new genus and species of ascomycetes, Catulus aquilonius, is described, illustrated, and tentatively assigned to the Mycosphaerellaceae. It grows as a parasite on stromata of Seuratia millardetii (Raciborski) Meeker and is characterized by two-celled, setulose ascospores.

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Abundance and Impacts of Competing Species on Conifer Regeneration Following Careful Logging in the Eastern Canadian Boreal Forest

Forests ◽

10.3390/f10020177 ◽

2019 ◽

Vol 10 (2) ◽

pp. 177 ◽

Cited By ~ 3

Author(s):

Louis-Philippe Ménard ◽

Jean-Claude Ruel ◽

Nelson Thiffault

Keyword(s):

Boreal Forest ◽

Basal Area ◽

Low Fertility ◽

Percent Cover ◽

Large Area ◽

Competing Species ◽

Competing Vegetation ◽

Conifer Regeneration ◽

Ericaceous Shrubs ◽

Canadian Boreal Forest

Managing competing vegetation is crucial in stand establishment strategies; forecasting the abundance, composition, and impact of competing vegetation after harvesting is needed to optimize silviculture scenarios and maintain long-term site productivity. Our main objective was to identify factors influencing the short-term abundance and composition of competing vegetation over a large area of the Canadian boreal forest. Our second objective was to better understand the mid-term evolution of the regeneration/competing vegetation complex in cases of marginal regeneration conditions. We used operational regeneration surveys of 4471 transects sampled ≈5 years after harvesting that contained data on regeneration, competing vegetation, elevation, ecological classification, soil attributes, and pre-harvest forest stands. We performed a redundancy analysis to identify the relationships between competing vegetation, harvesting and biophysical variables. We then estimated the probability of observing a given competing species cover based on these variables. In 2015, we re-sampled a portion of the sites, where conifer regeneration was marginal early after harvesting, to assess the temporal impact of different competing levels and species groups on the free-to-grow stocking, vigour and basal area of softwood regeneration. Results from the first inventory showed that, after careful logging around advance growth, ericaceous shrubs and hardwoods were not associated with the same sets of site attributes. Ericaceous shrubs were mainly found on low fertility sites associated with black spruce (Picea mariana (Mill.) BSP) or jack pine (Pinus banksiana Lamb.). The distinction between suitable environments for commercial shade-intolerant hardwoods and non-commercial hardwoods was less clear, as they responded similarly to many variables. Analysis of data from the second inventory showed a significant improvement in conifer free-to-grow stocking when commercial shade-intolerant hardwood competing levels were low (stocking 0%–40%) and when ericaceous shrubs competing levels were moderate (percent cover 26%–75%). In these conditions of marginal regeneration, the different types and intensities of competition did not affect the vigour or basal area of softwood regeneration, 9–14 years after harvesting.

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Breeding value of Norway spruce (Picea abies [L.] Karst.)

Journal of Forest Science ◽

10.17221/4596-jfs ◽

2012 ◽

Vol 50 (No. 1) ◽

pp. 17-23

Author(s):

Rożkowski KR

Keyword(s):

Survival Rate ◽

Norway Spruce ◽

Growth Traits ◽

Block Design ◽

Basal Area ◽

Tree Height ◽

Breeding Value ◽

Cross Sectional ◽

Qualitative Traits ◽

Crown Density

This is the first report on measurements and observations of an experimental plot of 35-year-old Norway spruce, established in 1970 by the Institute of Dendrology at Kórnik, where progenies of 22 plustrees from the Kłodzko Forest District were planted. The experiment was established in an incomplete block design of 20 families with 3 replications. Survival rate and growth traits determining productivity (plant height or basal area – stem cross-sectional area at breast height per 1 ha) were assessed in several years, and qualitative traits (trunk straightness; degree of natural pruning; thickness, length and angle of branches; crown density; presence of galls caused by the aphids Adelges laricis Vall. and Sacchiphantes viridis Ratz.) were evaluated once in 2001. Analysis of variance revealed significant differences between the half-sib families in survival rate and productivity but no significant differences in qualitative traits. Statistically significant positive correlations were found between trunk straightness at the age of<br /> 36 years and height of 2-year-old seedlings in the nursery, and between the degree of natural pruning at the age of 36 years and both tree height at the age of 9 years and basal area at the age of 13 years.

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A Comparison of the Arithmetic and Geometric Means in Estimating Stump Diameter, Basal Area, and Volume in Appalachian Hardwoods

Northern Journal of Applied Forestry ◽

10.1093/njaf/24.1.71 ◽

2007 ◽

Vol 24 (1) ◽

pp. 71-73 ◽

Cited By ~ 1

Author(s):

Harry V. Wiant ◽

John R. Brooks

Keyword(s):

Geometric Mean ◽

Basal Area ◽

Cross Sectional Area ◽

Practical Significance ◽

Sectional Area ◽

Cross Sectional ◽

Geometric Means ◽

The Difference ◽

Appalachian Hardwoods ◽

Stump Diameter

Abstract The difference between the use of the arithmetic and geometric means for estimation of average stump diameter, stump cross-sectional area and estimated tree volume was investigated using measurements from 739 stumps from an Appalachian hardwood stand located in central West Virginia. Although average stump diameter, cross-sectional area, and tree volumes were statistically different between estimates based on the arithmetic and geometric mean diameter, these differences were of little practical significance. The difference in average stem diameter, cross-sectional area, tree cubic volume, and board foot volume were 0.05 in, 0.01 ft2, 0.45 ft3, and 2.41 bd ft, respectively.

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Acoustic-Based Prediction of End-Product-Based Fibre Determinates within Standing Jack Pine Trees

Forests ◽

10.3390/f10070605 ◽

2019 ◽

Vol 10 (7) ◽

pp. 605

Author(s):

Peter F. Newton

Keyword(s):

Wood Density ◽

Pinus Banksiana ◽

Goodness Of Fit ◽

Prediction Models ◽

Microfibril Angle ◽

Model Performance ◽

Predictive Ability ◽

Analytical Framework ◽

Jack Pine ◽

Cross Sectional

The objective of this study was to specify, parameterize, and evaluate an acoustic-based inferential framework for estimating commercially-relevant wood attributes within standing jack pine (Pinus banksiana Lamb) trees. The analytical framework consisted of a suite of models for predicting the dynamic modulus of elasticity (me), microfibril angle (ma), oven-dried wood density (wd), tracheid wall thickness (wt), radial and tangential tracheid diameters (dr and dt, respectively), fibre coarseness (co), and specific surface area (sa), from dilatational stress wave velocity (vd). Data acquisition consisted of (1) in-forest collection of acoustic velocity measurements on 61 sample trees situated within 10 variable-sized plots that were established in four mature jack pine stands situated in boreal Canada followed by the removal of breast-height cross-sectional disk samples, and (2) given (1), in-laboratory extraction of radial-based transverse xylem samples from the 61 disks and subsequent attribute determination via Silviscan-3. Statistically, attribute-specific acoustic prediction models were specified, parameterized, and, subsequently, evaluated on their goodness-of-fit, lack-of-fit, and predictive ability. The results indicated that significant (p ≤ 0.05) and unbiased relationships could be established for all attributes but dt. The models explained 71%, 66%, 61%, 42%, 30%, 19%, and 13% of the variation in me, wt, sa, co, wd, ma, and dr, respectively. Simulated model performance when deploying an acoustic-based wood density estimate indicated that the expected magnitude of the error arising from predicting dt, co, sa, wt, me, and ma prediction would be in the order of ±8%, ±12%, ±12%, ±13%, ±20%, and ±39% of their true values, respectively. Assessment of the utility of predicting the prerequisite wd estimate using micro-drill resistance measures revealed that the amplitude-based wd estimate was inconsequentially more precise than that obtained from vd (≈ <2%). A discourse regarding the potential utility and limitations of the acoustic-based computational suite for forecasting jack pine end-product potential was also articulated.

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