Paper birch competitive effects vary with conifer tree species and stand age in interior British Columbia forests: implications for reforestation policy and practice

2004 ◽  
Vol 198 (1-3) ◽  
pp. 55-74 ◽  
Author(s):  
Suzanne W Simard ◽  
Donald L Sachs ◽  
Alan Vyse ◽  
Leandra L Blevins
Keyword(s):  
British Columbia ◽  
Tree Species ◽  
Stand Age ◽  
Policy And Practice ◽  
Competitive Effects ◽  
Paper Birch ◽  
Conifer Tree ◽  
Reforestation Policy

scholarly journals Effects of manual brushing on 10-year survival and growth of Douglas-fir in the mixed broadleaf – shrub complex of southern interior British Columbia

2020 ◽  
Vol 96 (02) ◽  
pp. 152-164
Author(s):  
George Harper ◽  
Kevin Brown
Keyword(s):  
British Columbia ◽  
Linear Models ◽  
Douglas Fir ◽  
Boundary Line ◽  
Exponential Relationship ◽  
Competitive Effects ◽  
Paper Birch ◽  
Survival And Growth ◽  
Negative Exponential ◽  
Density Boundary

Manual brushing is used to minimize the competitive effects of paper birch (Betula papyrifera Marsh) and associated broadleaved trees on young Douglas-fir (Pseudotsuga menziesii var. glauca) in southern interior British Columbia. Effects of brushing broadleaved trees, predominantly birch, on interior Douglas-fir survival and growth were studied on four sites. Treatments were applied when plantations were five to nine years old. Through 10 years post treatment, brushing did not affect Douglas-fir survival, but increase height by 22 % and stem diameter by 31 % and the differences were greater than seen at five years. After 10 years, linear models described a declining Douglas-fir height or diameter with increasing broadleaved tree density. Boundary line analysis was used to describe maximum treatment response to broadleaved density and two distance independent competition indices for birch and broadleaves, combining either cover or density with relative heights (CRH, DRH, respectively). A negative exponential relationship was fit to 10-year Douglas-fir heights and diameters with increasing values CRH or DRH. Competition thresholds for density, CRH and DRH were not apparent. The quantile regression results indicated the 10-year response of young Douglas-fir diameter to brushing occurred primarily with the largest 55 % to 85 % of the population, CRH and DRH respectively.

Assessment of interspecific competition using relative height and distance indices in an age sequence of seral interior cedar–hemlock forests in British Columbia

2004 ◽  
Vol 34 (6) ◽  
pp. 1228-1240 ◽  
Author(s):  
Suzanne W Simard ◽  
Donald L Sachs
Keyword(s):  
British Columbia ◽  
Interspecific Competition ◽  
Douglas Fir ◽  
Thuja Plicata ◽  
Stand Age ◽  
Relative Height ◽  
Larix Occidentalis ◽  
Critical Height ◽  
Paper Birch ◽  
Neighbourhood Analysis

Treatments that reduce neighbour density are widely applied in the belief they will improve conifer growth in mixed forests. However, our understanding of stand composition and age effects on competition is poor. We used neighbourhood analysis for 748 target conifer trees to examine interspecific competition within 11-, 25-, and 50-year-old mixed, even-aged stands of paper birch (Betula papyrifera Marsh.), Douglas-fir (Pseudotsuga menziesii var. glauca (Beissn.) Franco), western redcedar (Thuja plicata Donn ex D. Don), and western larch (Larix occidentalis Nutt.) in southern interior British Columbia. Critical neighbourhood height and distance were identified where competition accounted for the greatest variation in target conifer diameter. Competition processes were emperically examined using relative height indices. We found that critical neighbourhood distance increased with stand age and was greater for larch than for cedar. Critical neighbourhood height was higher for cedar than for Douglas-fir or larch in the 11-year-old stands but lower in the older stands. The most important competitors in the 11-year-old stands were tall neighbours, whereas those in the older stands were short neighbours. We found asymmetrical relationships between target conifers and neighbours for all species and age-classes, indicating a resource preemption mode of competition. To be useful in developing prescriptions for competition management in mixed species stands, competition indices should consider neighbour identity and critical height for each target species. Assessment radius must also be sufficiently large to adequately characterize competition.

Growth responses of seven major co-occurring tree species of the northeastern United States to elevated CO2

1990 ◽  
Vol 20 (9) ◽  
pp. 1479-1484 ◽  
Author(s):  
F. A. Bazzaz ◽  
J. S. Coleman ◽  
S. R. Morse
Keyword(s):  
Tree Species ◽  
Sugar Maple ◽  
Growth Enhancement ◽  
Black Cherry ◽  
Red Maple ◽  
Growth Responses ◽  
White Pine ◽  
American Beech ◽  
Harvard Forest ◽  
Paper Birch

We examined how elevated CO2 affected the growth of seven co-occurring tree species: American beech (Fagusgrandifolia Ehrh.), paper birch (Betulapapyrifera Marsh.), black cherry (Prunusserotina Ehrh.), white pine (Pinusstrobus L.), red maple (Acerrubrum L.), sugar maple (Acersaccharum Marsh.), and eastern hemlock (Tsugacanadensis (L.) Carr). We also tested whether the degree of shade tolerance of species and the age of seedlings affected plant responses to enhanced CO2 levels. Seedlings that were at least 1 year old, for all species except beech, were removed while dormant from Harvard Forest, Petersham, Massachusetts. Seeds of red maple and paper birch were obtained from parent trees at Harvard Forest, and seeds of American beech were obtained from a population of beeches in Nova Scotia. Seedlings and transplants were grown in one of four plant growth chambers for 60 d (beech, paper birch, red maple, black cherry) or 100 d (white pine, hemlock, sugar maple) under CO2 levels of 400 or 700 μL•L−1. Plants were then harvested for biomass and growth determinations. The results showed that the biomass of beech, paper birch, black cherry, sugar maple, and hemlock significantly increased in elevated CO2, but the biomass of red maple and white pine only marginally increased in these conditions. Furthermore, there were large differences in the magnitude of growth enhancement by increased levels of CO2 between species, so it seems reasonable to predict that one consequence of rising levels of CO2 may be to increase the competitive ability of some species relative to others. Additionally, the three species exhibiting the largest increase in growth with increased CO2 concentrations were the shade-tolerant species (i.e., beech, sugar maple, and hemlock). Thus, elevated CO2 levels may enhance the growth of relatively shade-tolerant forest trees to a greater extent than growth of shade-intolerant trees, at least under the light and nutrient conditions of this experiment. We found no evidence to suggest that the age of tree seedlings greatly affected their response to elevated CO2 concentrations.

scholarly journals Tree species richness increases ecosystem carbon storage in subtropical forests

2018 ◽  
Vol 285 (1885) ◽  
pp. 20181240 ◽  
Author(s):  
Xiaojuan Liu ◽  
Stefan Trogisch ◽  
Jin-Sheng He ◽  
Pascal A. Niklaus ◽  
Helge Bruelheide ◽  
...  
Keyword(s):  
Species Richness ◽  
Tree Species ◽  
C Sequestration ◽  
Stand Age ◽  
Southeast China ◽  
Subtropical Forests ◽  
C Stocks ◽  
C Stock ◽  
Below Ground ◽  
Time Periods

Forest ecosystems are an integral component of the global carbon cycle as they take up and release large amounts of C over short time periods (C flux) or accumulate it over longer time periods (C stock). However, there remains uncertainty about whether and in which direction C fluxes and in particular C stocks may differ between forests of high versus low species richness. Based on a comprehensive dataset derived from field-based measurements, we tested the effect of species richness (3–20 tree species) and stand age (22–116 years) on six compartments of above- and below-ground C stocks and four components of C fluxes in subtropical forests in southeast China. Across forest stands, total C stock was 149 ± 12 Mg ha −1 with richness explaining 28.5% and age explaining 29.4% of variation in this measure. Species-rich stands had higher C stocks and fluxes than stands with low richness; and, in addition, old stands had higher C stocks than young ones. Overall, for each additional tree species, the total C stock increased by 6.4%. Our results provide comprehensive evidence for diversity-mediated above- and below-ground C sequestration in species-rich subtropical forests in southeast China. Therefore, afforestation policies in this region and elsewhere should consider a change from the current focus on monocultures to multi-species plantations to increase C fixation and thus slow increasing atmospheric CO 2 concentrations and global warming.

scholarly journals A Pine Is a Pine and a Spruce Is a Spruce – The Effect of Tree Species and Stand Age on Epiphytic Lichen Communities

PLoS ONE ◽  
2016 ◽  
Vol 11 (1) ◽  
pp. e0147004 ◽  
Author(s):  
Sofia Bäcklund ◽  
Mari Jönsson ◽  
Joachim Strengbom ◽  
Andreas Frisch ◽  
Göran Thor
Keyword(s):  
Tree Species ◽  
Stand Age ◽  
Epiphytic Lichen

scholarly journals A test of the hydraulic vulnerability segmentation hypothesis in angiosperm and conifer tree species

2016 ◽  
Vol 36 (8) ◽  
pp. 983-993 ◽  
Author(s):  
Daniel M. Johnson ◽  
Remi Wortemann ◽  
Katherine A. McCulloh ◽  
Lionel Jordan-Meille ◽  
Eric Ward ◽  
...  
Keyword(s):  
Tree Species ◽  
Hydraulic Vulnerability ◽  
Conifer Tree

Forest reproduction methods for coastal British Columbia: Principles, criteria, and a stand selection guide

1994 ◽  
Vol 70 (5) ◽  
pp. 569-577 ◽  
Author(s):  
K. Klinka ◽  
G. J. Kayahara ◽  
R. E. Carter
Keyword(s):  
British Columbia ◽  
Tree Species ◽  
Stand Structure ◽  
Species Selection ◽  
Cutting Method ◽  
Management Objectives ◽  
Dichotomous Key ◽  
Management Factors ◽  
Reproduction Method ◽  
Coastal British Columbia

Once a decision to regenerate a particular stand is made at the forest level, a forester has to make critical decisions at the stand level as to the choice of cutting method for existing stands to regenerate the desired species and develop a stand of the desired structure. Two related critical decisions in stand-level forest management are (1) selecting the best tree species to regenerate on a given site, and (2) selecting the appropriate method of cutting existing stands for both the regeneration of the desired species within a certain time and for maintaining or developing the desired stand structure. This paper discusses the management factors and principles and criteria for choosing a cutting method to meet decision (2) (i.e., the reproduction method). The four criteria used to guide the appropriate reproduction method are (1) maximum sustainable forest productivity, (2) stand reliability, (3) silvicultural feasibility, and (4) harvesting feasibility. With these criteria in mind, a stand-level guide devised for coastal British Columbia is proposed. This guide is in the form of a dichotomous key and is based on 13 selected ecological, stand, and management factors. Combining this approach with principles, criteria and guidelines for tree species selection already practiced, regeneration and management objectives can be achieved both on a species-and site-specific basis. Key words: forest reproduction methods, decision support systems, silvicultural prescriptions, harvesting methods, stand regeneration, stand structure

scholarly journals An Individual-Tree Mortality Model for Complex Stands of Southeastern British Columbia

2005 ◽  
Vol 20 (2) ◽  
pp. 101-109 ◽  
Author(s):  
Hailemariam Temesgen ◽  
Stephen J. Mitchell
Keyword(s):  
British Columbia ◽  
Tree Species ◽  
Tree Mortality ◽  
Model Development ◽  
Mortality Rates ◽  
Average Deviation ◽  
Individual Tree ◽  
Permanent Sample Plots ◽  
Diameter Increment ◽  
Mortality Model

Abstract An individual-tree mortality model was developed for major tree species in complex stands (multi-cohort, multiaged, and mixed species) of southeastern British Columbia (BC), Canada. Data for 29,773 trees were obtained from permanent sample plots established in BC. Average annual diameter increment and mortality rates ranged from 0.08 to 0.17 cm/year and from 0.3 to 2.6%, respectively. Approximately 70% of the trees were used for model development and 30% for model evaluation. After evaluating the model, all 29,773 trees were used to fit the final model. A generalized logistic model was used to relate mortality to tree size, competition, and relative position of trees in a stand. The evaluation test demonstrated that the model appears to be well behaved and robust for the tree species considered in this study. For the eight tree species, the average deviation between observed and predicted annual mortality rates varied from −0.5 to 0.7% in the test data. West. J. Appl. For. 20(2):101–109.

Sign in / Sign up

Export Citation Format

Share Document