Histochemistry of the dormant vascular cambium of Abies balsamea: changes associated with tree age and crown position

1986 ◽  
Vol 64 (9) ◽  
pp. 2082-2087 ◽  
Author(s):  
R. T. Riding ◽  
C. H. A. Little
Keyword(s):  
Abies Balsamea ◽  
Experimental Period ◽  
Vascular Cambium ◽  
Balsam Fir ◽  
Tree Age ◽  
Controlled Environment ◽  
Cytoplasmic Rna ◽  
Cambial Zone ◽  
Old Trees ◽  
Cambial Dormancy

On three dates during September–December, the histochemistry and dormancy status of cambial zone cells were investigated in 6- and 19-year-old balsam fir (Abies balsamea) trees at the top of the crown (1-year-old cambium) and near the base of the bole (5- and 13-year-old cambium, respectively). The extent of dormancy on the date of collection and after 4 weeks in controlled-environment conditions favorable for growth indicated that a changeover between the dormancy stages of rest and quiescence occurred in all ages of the cambium during the experimental period. In trees of both ages, cambial dormancy began later, and the number of fusiform cells in the cambial zone was greater at the bottom of the tree than at the top. The staining intensities for total cytoplasmic RNA, protein, and insoluble carbohydrates in the fusiform cambial zone cells increased during the rest–quiescence transition at the top and bottom of the 6-year-old trees and at the top of the 19-year-old trees. However, no significant increase in RNA staining occurred at the bottom of the 19-year-old trees.

Effect of cambial dormancy state on the transport of [1-14C]indol-3-ylacetic acid in Abies balsamea shoots

1981 ◽  
Vol 59 (3) ◽  
pp. 342-348 ◽  
Author(s):  
C. H. A. Little
Keyword(s):  
Abies Balsamea ◽  
Cambial Activity ◽  
Controlled Environment ◽  
Long Distance ◽  
Dormant Period ◽  
Cambial Zone ◽  
Time Required ◽  
Ylacetic Acid ◽  
Exogenous Iaa

Dormant attached or detached shoots of balsam fir were naturally or artificially chilled to induce different states along the rest–quiescence continuum. At the end of the chilling pretreatment, the shoots either were left intact or were debudded and treated with indol-3-ylacetic acid (IAA). The shoots were placed under controlled-environment conditions favorable for growth, and at intervals thereafter, a pulse of [1-14C]IAA was applied to the shoot apex. Measured at the end of the chilling pretreatment, [14C]IAA velocity and flux decreased with increasing duration of chilling (i.e., as rest graded into quiescence). The time required to commence cambial growth and to attain maximum rates of cambial activity and [14C]IAA transport also decreased as rest changed to quiescence. Transport in actively growing shoots exceeded that in quiescent shoots, but was similar to that in resting shoots. The [14C]IAA pulse moved basipetally as unchanged IAA, was blocked by a bark + cambium girdle, and was inhibited by abscisic acid and long-term application of exogenous IAA. The results indicate that: (1) the long-distance, cambium-located, IAA transport system demonstrated in dicotyledonous species also operates in conifers, (2) during the dormant period changes occur in [14C]IAA transport and in the cambial response to exogenous IAA, (3) the change in [14C]IAA transport is the result of change in the transporting capability of cells in the cambial zone, and (4) the change in [14C]IAA transport is not the cause of the differential response of quiescent and resting cambia to exogenous IAA.

Derivation of the springtime starch increase in balsam fir (Abies balsamea)

1970 ◽  
Vol 48 (11) ◽  
pp. 1995-1999 ◽  
Author(s):  
C. H. A. Little
Keyword(s):  
Starch Content ◽  
Abies Balsamea ◽  
Experimental Period ◽  
Shoot Elongation ◽  
Early Spring ◽  
Total Sugar ◽  
Carbohydrate Content ◽  
Balsam Fir ◽  
Conifer Seedlings

The contents of starch, total sugar, crude fat, and moisture were determined during the spring (late March until mid-June) in needles, bark, and wood of 1-year-old balsam fir shoots variously shaded, defoliated, and girdled in late March. The starch content in control shoots peaked during the first week in June, about the time vigorous current shoot elongation began. Shading reduced the concentrations of both starch and total sugar throughout the experimental period, while defoliation decreased them after about mid-spring. Girdling increased the carbohydrate content during early spring in both shaded and unshaded shoots, but decreased it in defoliated shoots. It is concluded that the bulk of the starch accumulating in conifers during the spring is derived from current photosynthesis, the rest being regenerated from carbohydrates produced during the previous year and stored overwinter. Timing the lifting date to maximize the springtime accumulation of starch might be an important consideration when transplanting conifer seedlings.

Sapwood/Heartwood Width Relationships with Tree Age in Balsam Fir

IAWA Journal ◽  
1991 ◽  
Vol 12 (1) ◽  
pp. 95-99 ◽  
Author(s):  
G. Hazenberg ◽  
K. C. Yang
Keyword(s):  
Abies Balsamea ◽  
Basal Area ◽  
Ring Expansion ◽  
Balsam Fir ◽  
Tree Age ◽  
Thunder Bay ◽  
Wide Range ◽  
The Cost ◽  
The University ◽  
Response Variables

On the basis of five response variables, the sapwood/heartwood relationships with tree age were studied in balsam fir [Abies balsamea (L.) Mill.] trees. One hundred and one samples, from a wide range of stand densities, were collected from the university forest near Thunder Bay, Ontario. The age at breast height ranged from 4 to 85 years. The five response variables measured were the number of sapwood and heartwood rings, sapwood and heartwood width and sapwood basal area. First and second degree polynomials in tree age were fitted for the five response variables and the best fit for each, based on the significance of the regression coefficients, was selected. The number of heartwood rings expanded quite rapidly to 0.81 ring per year, at the cost of sapwood ring expansion which averaged 0.19 ring per year.

Balsam fir (Abies balsamea) establishment dynamics during a spruce budworm (Choristoneura fumiferana) outbreak: an evaluation of the impact of aging techniques

2001 ◽  
Vol 31 (3) ◽  
pp. 373-376 ◽  
Author(s):  
Sylvain Parent ◽  
Hubert Morin ◽  
Christian Messier
Keyword(s):  
Conventional Method ◽  
Seedling Recruitment ◽  
Choristoneura Fumiferana ◽  
Abies Balsamea ◽  
Spruce Budworm ◽  
Adult Mortality ◽  
Balsam Fir ◽  
Tree Age ◽  
Terminal Bud ◽  
The Impact

The effects of recurrent spruce budworm (Choristoneura fumiferana (Clem.)) outbreaks on balsam fir (Abies balsamea (L.) Mill.) mortality have been extensively studied in Canada. Most studies report substantial seedling recruitment of balsam fir during outbreaks when reproductive trees are dying. According to previous research, this contradiction could be due to inaccuracies in the conventional aging method. Counting the maximum number of growth rings found at the tree base would significantly underestimate tree age. Counting terminal bud scars found on the entire trunk, including buried stem, would give a more accurate tree age. In this study, we compare recruitment dynamics obtained for aging seedlings in two balsam fir populations (about 500 km apart) using (i) the conventional method and (ii) bud scar counts. For both populations, the conventional method shows substantial recruitment during adult mortality, while the second aging technique reveals reduced recruitment during the epidemic phase of the spruce budworm outbreak.

scholarly journals Potential of Alnus acuminata based agroforestry for carbon sequestration and other ecosystem services in Rwanda

2021 ◽  
Author(s):  
Athanase R. Cyamweshi ◽  
Shem Kuyah ◽  
Athanase Mukuralinda ◽  
Catherine W. Muthuri
Keyword(s):  
Ecosystem Services ◽  
Carbon Sequestration ◽  
Soil Fertility ◽  
Tree Age ◽  
Average Height ◽  
Total Biomass ◽  
Biomass Carbon ◽  
Alnus Acuminata ◽  
Sequestration Potential ◽  
Old Trees

AbstractAlnus acuminata Kunth. (alnus) is widely used in agroforestry systems across the globe and is believed to provide multiple ecosystem services; however, evidence is lacking in agroforestry literature to support the perceived benefits, particularly in Rwanda. To understand carbon sequestration potential and other benefits of alnus, a household survey, tree inventory and destructive sampling were conducted in north-western Rwanda. Over 75% of the respondents had alnus trees in their farms. The trees provide stakes for climbing beans, firewood and timber. They also improve soil fertility and control soil erosion. Farmers had between 130 and 161 alnus trees per hectare with an average height of 7.7 ± 0.59 m and diameter at breast height of 16.3 ± 1.39 cm. The largest biomass proportion was found in stems (70.5%) while branches and leaves stock about 16.5 and 13% of the total biomass, respectively. At farm level, aboveground biomass of alnus trees was estimated to be 27.2 ± 0.7 Mg ha−1 representing 13.6 Mg of carbon (C) per hectare. Biomass carbon increased with tree size, from 7.1 ± 0.2 Mg C ha−1 in 3 years old trees to 34.4 ± 2.2 Mg C ha−1 in 10 years old trees. The converse was observed with elevation; biomass carbon decreased with increasing elevation from 21.4 ± 1.29 Mg C ha−1 at low (2011–2110 m) to 9.6 ± 0.75 Mg C ha−1 in the high elevation (> 2510 m). In conclusion, alnus agroforestry significantly contributes to carbon sequestration, although the magnitude of these benefits varies with tree age and elevation. Planting alnus trees on farms can meet local needs for stakes for climbing beans, wood and soil fertility improvement, as well as the global need for regulation of climate change.

Weather and Outbreaks of the Spruce Budworm in the Province of Quebec from 1939 to 1956

1961 ◽  
Vol 93 (2) ◽  
pp. 118-123 ◽  
Author(s):  
J. G. Pilon ◽  
J. R. Blais
Keyword(s):  
Choristoneura Fumiferana ◽  
Abies Balsamea ◽  
Spruce Budworm ◽  
Balsam Fir ◽  
The Past ◽  
Forest Regions ◽  
Tree Component ◽  
Gaspe Peninsula ◽  
Gaspé Peninsula

Nearly all forest regions in the Province of Quebec where balsam fir (Abies balsamea (L.) Mill.) is an important tree component have been subjected to severe defoliation by the spruce budworm, Choristoneura fumiferana (Clem.), during the past 20 years. These outbreaks have followed an easterly direction beginning near the Ontario-Quebec border in 1939 and ending in the Gaspé Peninsula in 1958.

scholarly journals Mixed Regional Shifts in Conifer Productivity under 21st-Century Climate Projections in Canada’s Northeastern Boreal Forest

Forests ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 248
Author(s):  
Tyler Searls ◽  
James Steenberg ◽  
Xinbiao Zhu ◽  
Charles P.-A. Bourque ◽  
Fan-Rui Meng
Keyword(s):  
Climate Change ◽  
Model Validation ◽  
21St Century ◽  
Black Spruce ◽  
Abies Balsamea ◽  
Acer Rubrum ◽  
Forest Growth ◽  
Balsam Fir ◽  
Growth And Yield ◽  
Climate Projections

Models of forest growth and yield (G&Y) are a key component in long-term strategic forest management plans. Models leveraging the industry-standard “empirical” approach to G&Y are frequently underpinned by an assumption of historical consistency in climatic growing conditions. This assumption is problematic as forest managers look to obtain reliable growth predictions under the changing climate of the 21st century. Consequently, there is a pressing need for G&Y modelling approaches that can be more robustly applied under the influence of climate change. In this study we utilized an established forest gap model (JABOWA-3) to simulate G&Y between 2020 and 2100 under Representative Concentration Pathways (RCP) 2.6, 4.5, and 8.5 in the Canadian province of Newfoundland and Labrador (NL). Simulations were completed using the province’s permanent sample plot data and surface-fitted climatic datasets. Through model validation, we found simulated basal area (BA) aligned with observed BA for the major conifer species components of NL’s forests, including black spruce [Picea mariana (Mill.) Britton et al.] and balsam fir [Abies balsamea (L.) Mill]. Model validation was not as robust for the less abundant species components of NL (e.g., Acer rubrum L. 1753, Populus tremuloides Michx., and Picea glauca (Moench) Voss). Our simulations generally indicate that projected climatic changes may modestly increase black spruce and balsam fir productivity in the more northerly growing environments within NL. In contrast, we found productivity of these same species to only be maintained, and in some instances even decline, toward NL’s southerly extents. These generalizations are moderated by species, RCP, and geographic parameters. Growth modifiers were also prepared to render empirical G&Y projections more robust for use under periods of climate change.

Prescribed Burning for Stand Conversion in Budworm-killed Balsam Fir: An Ontario Case History

1986 ◽  
Vol 62 (2) ◽  
pp. 96-100 ◽  
Author(s):  
D. J. McRae
Keyword(s):  
Fuel Consumption ◽  
Prescribed Burning ◽  
Choristoneura Fumiferana ◽  
Abies Balsamea ◽  
Spruce Budworm ◽  
Fire Spread ◽  
Fire Effects ◽  
Balsam Fir ◽  
Prescribed Burn ◽  
Stand Conversion

Recent spruce budworm (Choristoneura fumiferana [Clem.]) infestations have resulted in widespread areas of balsam fir (Abies balsamea [L.] Mill.) mortality in Ontario, and there is growing interest in reestablishing these areas quickly as productive forests. One technique being used is prescribed fire after a salvage and bulldozer tramping operation. A 445-ha prescribed burn was carried out under moderate fire danger conditions in northern Ontario. The site, which was covered by balsam fir fuel that had been killed by spruce budworm, was tramped to improve fire spread. Weather, fuel consumption, and fire effects are reported. The burn effectively reduced heavy surface fuel loadings and consequently planting on the site was easier. Key words: Prescribed burning, fire, spruce budworm. Choristoneura fumiferana, balsam fir, Abies balsamea, fuel consumption, site preparation, tramping, stand conversion.

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