Wet Heartwood Distribution in the Stem, Stump, and Root Wood of Black Spruce in the Quebec Boreal Forest, Canada

Abstract Wet heartwood has been studied since the beginning of the 20th century. The present work focused on wet heartwood of 44 black spruces (Picea mariana (Mill.) B.S.P.) from boreal forest swampy sites Quebec, Canada. Trees were studied to characterize their tree crown shape, quickly identify them in the field, measure their moisture content, establish their moisture content distribution pattern, evaluate the wet heartwood volume inside their stem, and find the possibility of water entrance in this species. Black spruces with wet heartwood were characterized by a typical tree shape with a small number of living branches, short branches, and a clump of green needles at the top of the tree. The wet heartwood was characterized by high moisture content at the stem base and decreased with stem height. Wet heartwood was observed as high as 5 m above stem base for trees around 10.5 m in height. Moisture content of sapwood along the stem varied from 81 to 161%, whereas in dry heartwood, it was around 43% but reached more than 100% in the wet heartwood. Wet heartwood volume in the first 3.25 m of black spruce stems averaged 13% with variations between 2 and 35% per study site. Twelve stumps had wet heartwood moisture contents reaching 143% or higher. Moisture content of wet heartwood in root sections closest to the stump varied along a gradient: lower or absent at ground level and increasing with depth up to a maximum value before decreasing again. North. J. Appl. For. 22(1):12–18.

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Landscape-level variability in the age underestimation of understory black spruce in the northern boreal forest of Quebec

Canadian Journal of Forest Research ◽

10.1139/x04-181 ◽

2005 ◽

Vol 35 (3) ◽

pp. 633-642 ◽

Cited By ~ 4

Author(s):

Marc-André Parisien ◽

Luc Sirois ◽

Sylvain Parent

Keyword(s):

Boreal Forest ◽

Mixed Models ◽

Black Spruce ◽

Ground Level ◽

Simple Linear Regression ◽

Linear Regression Models ◽

Growth Rings ◽

Age Correction ◽

The Relationship ◽

Landscape Level

This study examines the variability of the potential aging error for saplings (height ≤1.5 m) of black spruce (Picea mariana (Mill.) B.S.P.) in mature fire-dominated stands (n = 14 stands) of the northern boreal forest of northwestern Quebec. Age underestimation was determined by counting the number of underground bud scars of saplings. The magnitude and variability of age underestimation was compared within and among stands. The relationship between corrected ages (the sum of age underestimation and the number of growth rings at ground level) and ground-level ages was strongly linear and was therefore described with simple linear regression models. To evaluate landscape-level variability in this relationship, the regressions were compared among stands using mixed models. Despite high variability in age underestimation at the stand level, the relationship between corrected and ground-level age was highly significant (p < 0.0001) for all stands except one. However, there were many significant statistical differences between these regressions, indicating high landscape-level variability. The magnitude of age underestimation was found to be highly site specific (means of 726 years), the phenomenon being more marked and variable in older stands. Given high landscape-level variability, age underestimation of understory black spruce saplings in northern boreal stands must be documented for every sampled stand to apply a valid age correction in studies that involve multiple stands.

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Fire severity as a determinant factor of the decomposition rate of fire-killed black spruce in the northern boreal forest

Canadian Journal of Forest Research ◽

10.1139/x10-218 ◽

2011 ◽

Vol 41 (2) ◽

pp. 370-379 ◽

Cited By ~ 16

Author(s):

Yan Boulanger ◽

Luc Sirois ◽

Christian Hébert

Keyword(s):

Moisture Content ◽

Boreal Forest ◽

Decomposition Rate ◽

Black Spruce ◽

Woody Debris ◽

Fire Severity ◽

Decomposition Process ◽

Vertical Position ◽

Decomposition Rates ◽

Considerable Impact

Several attributes might influence the decomposition process of fire-killed trees. Here, we tested various tree- and plot-level variables on the decomposition rate of fire-killed black spruce ( Picea mariana (Mill.) BSP) in the northern boreal forest. Data were collected from 474 individuals burned 17 years prior to sampling. Mean decomposition rate was relatively slow (k = 0.013) and was lowest for severely burned snags (k = 0.001) and highest for lightly burned logs (k = 0.027–0.036). Vertical position and fire severity were the most important variables influencing the decomposition rates, while plot-level variables were marginally significant. Both predictors strongly influenced the moisture content of fire-killed trees. Logs with greater contact with the ground and lightly burned trees had higher moisture content and faster decomposition rates. Very severely burned trees had lower moisture content because of faster bark shedding. This hampered the decomposition process by slowing the snag falling rate. Higher decomposition rates in lightly burned trees may result from greater colonization by early xylophagous species. By having a considerable impact on the decomposition of woody debris, fire severity may strongly influence many post-fire biological processes related to the woody necromass as well as carbon emission from burned stands.

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Postfire dynamics of black spruce coarse woody debris in northern boreal forest of Quebec

Canadian Journal of Forest Research ◽

10.1139/x06-070 ◽

2006 ◽

Vol 36 (7) ◽

pp. 1770-1780 ◽

Cited By ~ 54

Author(s):

Yan Boulanger ◽

Luc Sirois

Keyword(s):

Moisture Content ◽

Boreal Forest ◽

Nitrogen Content ◽

Decomposition Rate ◽

Coarse Woody Debris ◽

Black Spruce ◽

Woody Debris ◽

Decomposition Rates ◽

Asymbiotic Nitrogen Fixation ◽

Study Sites

In this study, postfire coarse woody debris (CWD) dynamics in northern Quebec, Canada, were assessed using a 29-year chronosequence. Postfire woody-debris storage, decomposition rates, and variation of nitrogen and carbon contents of black spruce CWD (Picea mariana (Mill.) BSP) are estimated. The decomposition rate for postfire snags is exceptionally slow (k = 0.00), while the decomposition rate for logs (k = 0.019–0.021) is within previously recorded values for the boreal forest. The low decomposition rate for snags could be related to low moisture content associated with the position of debris and fast bark shedding. Given the low CWD decomposition rates and CWD storage (21.3–66.8 m3·ha–1), carbon losses from postfire CWD are relatively low, varying between 35.5 and 128.8 kg·ha–1·year–1 at the study sites. The nitrogen content in CWD drops quickly between living trees and snags and increases slightly with time since fire in logs. Nitrogen content is not related to wood density or to moisture content of deadwood. Rapid loss of nitrogen is associated with fast decomposition of subcortical tissues, leaching, and insect comminution. The increase in nitrogen content at the oldest site could result from asymbiotic nitrogen fixation, although a longer time span in the chronosequence would probably have revealed a greater nitrogen gain in increasingly decayed CWD.

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Drying kinetics of processed natural coffee with high moisture content

Coffee Science ◽

10.25186/cs.v12i3.1320 ◽

2017 ◽

Vol 12 (3) ◽

pp. 400 ◽

Cited By ~ 3

Author(s):

Valdiney Cambuy Siqueira ◽

Flávio Meira Borém ◽

Guilherme Euripedes Alves ◽

Eder Pedroza Isquierdo ◽

Afonso Celso Ferreira Pinto ◽

...

Keyword(s):

Moisture Content ◽

Drying Kinetics ◽

High Moisture Content ◽

High Moisture ◽

Kinetics Of

Objetivou-se, com o presente trabalho, propor um novo método de processamento e secagem, assim como avaliar o comportamento dos grãos submetidos a este processo, por meio da taxa de redução de água e do ajuste de diferentes modelos matemáticos aos dados experimentais da secagem. Os frutos colhidos no estágio maduro foram divididos em três lotes. O primeiro foi seco continuamente à temperatura de 40±1 °C. O segundo consiste na secagem do café natural até os teores de água de 0,56±0,02, 0,41±0,02, 0,28±0,02 e 0,20±0,02 decimal (base seca, b.s.), seguido de beneficiamento e secagem contínua nas temperaturas de 35±1 ºC e 40±1 ºC. O terceiro lote correspondeu à secagem contínua do café descascado e desmucilado na temperatura de 40±1 °C. Em todos os lotes, a secagem foi encerrada quando os grãos atingiram o teor de água de 0,12±0,05 (b.s.). Aos dados experimentais da secagem foram ajustados dez modelos matemáticos utilizados para representação da secagem dos produtos agrícolas. Além da representação da cinética de secagem foi avaliada a taxa de redução de água dos grãos. Conclui-se que a taxa de redução de água é maior para a temperatura de secagem de 40±1 °C, especialmente para maiores teores de água. O tempo total de secagem do café beneficiado com alto teor de água é expressivamente reduzido, quando comparado ao tempo de secagem completa do café natural. O modelo de Midilli descreve satisfatoriamente a cinética de secagem do café beneficiado.

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Effects of Storing High Moisture Content Rough Rice on Subsequent Drying Characteristics and Milling Quality

10.13031/2013.9713 ◽

2002 ◽

Author(s):

JM Manski ◽

TJ Siebenmorgen ◽

AL Matsler

Keyword(s):

Moisture Content ◽

High Moisture Content ◽

High Moisture ◽

Drying Characteristics ◽

Milling Quality ◽

Rough Rice

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Intensive beef production 6. A note on the nutritive value of high moisture barley stored anaerobically

Animal Science ◽

10.1017/s0003356100025836 ◽

1965 ◽

Vol 7 (3) ◽

pp. 385-387 ◽

Cited By ~ 4

Author(s):

T. R. Preston ◽

H. B. Bowers ◽

N. A. MacLeod ◽

Euphemia B. Phillip

Keyword(s):

Moisture Content ◽

Nutritive Value ◽

Feeding System ◽

Beef Production ◽

Anaerobic Conditions ◽

High Moisture ◽

Roller Mill ◽

Barley Husk

The use of barley for intensive beef production, as described by Preston, Aitken, Whitelaw, Macdearmid, MacLeod and Philip (1963) is now a well established practice, but one of the hazards of this feeding system is bloat. There is evidence that the risk of this condition is accentuated if the barley husk is broken down too finely as happens if the grain is ground (Preston, Macdearmid and MacLeod, 1963; Preston, 1964). It was therefore recommended that barley should be processed in a roller mill and that the moisture content should be at least 16% (Preston, 1963), for if the grain is drier than this it is difficult to prevent excessive shattering and destruction of the husk. Suitable containers, which can be sealed in order to ensure anaerobic conditions and so overcome the problem of storing damp grain (greater than 16% moisture) have additional advantages at harvest since they can be filled quickly and easily. The purpose of this experiment was to evaluate the nutritive value of barley stored under these conditions.

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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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