Breast-height relative density and radial growth in mature jack pine (Pinusbanksiana) for 38 years after thinning

1994 ◽  
Vol 24 (12) ◽  
pp. 2439-2447 ◽  
Author(s):  
R. James Barbour ◽  
David C.F. Fayle ◽  
Gilles Chauret ◽  
Jean Cook ◽  
Marianne B. Karsh ◽  
...  
Keyword(s):  
Relative Density ◽  
Wood Quality ◽  
Jack Pine ◽  
Pulp Yield ◽  
Northern Ontario ◽  
Short Supply ◽  
Average Spacing ◽  
Breast Height ◽  
Commercial Thinning ◽  
Rotation Age

Sawlogs are in short supply in northern Ontario, and thinning has been suggested as one way to improve the situation. The only rotation-age jack pine (Pinusbanksiana Lamb.) thinning trial in the region was examined to assess how commercial thinning influenced wood quality. This report covers an unreplicated trial of a 65-year chronology of pith to bark relative densities and growth rates based on X-ray densitometry of breast-height increment cores taken from trees on two thinned plots (average spacing 2.6 and 3.4 m) and an unthinned control (average spacing 1.7 m). The trees on the treatment plots responded to thinning by producing wood with significantly lower relative density than those on the control plot. This trend continued much longer than reported for other pines and could negatively affect pulp yield or mechanical properties of lumber. Enhanced earlywood growth caused a drop in the proportion of latewood that resulted in the decline in density. Thinning may have improved moisture availability during the early and middle season and encouraged earlywood growth. Density and growth rate differences became apparent soon after treatment. Early, rapid, and inexpensive estimates of the product potential of younger thinning trials are possible using the techniques demonstrated here.

Polymorphic site index curves for jack pine in Northern Ontario

2001 ◽  
Vol 77 (1) ◽  
pp. 141-150 ◽  
Author(s):  
Willard H. Carmean ◽  
G. Hazenberg ◽  
G. P. Niznowski
Keyword(s):  
Analysis Data ◽  
Site Index ◽  
The United States ◽  
Jack Pine ◽  
Height Growth ◽  
Growth Patterns ◽  
Site Quality ◽  
Northern Ontario ◽  
Breast Height ◽  
The North

Stem-analysis data from dominant and codominant trees were collected from 383 plots located in fully stocked, even-aged, undisturbed mature jack pine stands. Separate site index curves were independently formulated for four regions of northern Ontario using the Newnham constrained nonlinear regression model; these formulations were used for comparing regional site index curves at three levels of site index (10 m, 15 m and 20 m).Comparisons showed that no significant differences existed between the four regional curves as well as with previously published site index curves for the North Central Region. Each of the four regions had similar polymorphic height-growth patterns; therefore, data for the four regions were combined and a single formulation was used to develop a polymorphic set of site index curves for all of northern Ontario. We found that poor sites in each region had almost linear height growth up to 100 years breast-height age, but for each region height growth became more curvilinear with increasing site index. The recommended site index curves for northern Ontario are based on a formulation using only data from plots 100 years and less but this formulation was not significantly different from a formulation using only data from plots 80 years and less, or a formulation that included all data from plots older than 100 years breast-height age.Comparisons were made between our northern Ontario curves and other jack pine site index curves for Ontario as well as curves for other areas of Canada and the United States. These comparisons generally showed considerable older age differences. Reasons for these differences are uncertain but could be due to differences in the amount and kind of data used for these other curves, could be due to differences in analytical methods, or could be due to regional differences in climate, soil and topography. Key words: site quality evaluation, polymorphic height growth, regional site index curves, site index prediction equations, comparisons among site index curves.

scholarly journals Effect of Seed Transfer on Selected Wood Quality Attributes of Jack Pine (Pinus banksiana Lamb.)

Forests ◽  
2019 ◽  
Vol 10 (11) ◽  
pp. 985
Author(s):  
Cyriac S. Mvolo ◽  
Ahmed Koubaa ◽  
Jean Beaulieu ◽  
Alain Cloutier
Keyword(s):  
Growth Rate ◽  
Pinus Banksiana ◽  
Juvenile Wood ◽  
Wood Quality ◽  
Jack Pine ◽  
Quality Attributes ◽  
Surprising Result ◽  
Breast Height ◽  
Seed Sources ◽  
Provenance Test

So far, few studies have considered the impacts of seed sources transfer on jack pine (Pinus banksiana Lamb.) wood quality, although wood quality attributes (WQA) in general and the differences between juvenile and mature wood in particular will determine suitability of the produced wood for end-uses. The main objective of this study was to examine the possibility of selecting superior jack pine provenances based on selected WQA. Twenty-two provenances of jack pine were planted in 1964 in Petawawa Research Forest, ON, Canada, as part of a provenance test. The plantation location offers conditions close to optimum for jack pine growth. Transition ages at breast height, determined with tracheids length, were computed with a piecewise model. Measurements at age 42 from seed were subjected to analyses of variance. Radial variations from pith to bark, as well as trends with seed sources origin of the selected WQA were also considered. A ranking was made based on a selection index built with four WQA. The provenances matured between 8 and 14 years, corresponding to 17%–48% of juvenile wood proportion. Significant differences among provenances were observed for ring width, ring density, tracheid length, and diameter at breast height but not for tracheid diameter, tree height, transition age, and juvenile wood proportion. None of the provenances ranked the best with all the selected WQA, but it was possible to find provenances exhibiting both high growth rate and good wood quality. A surprising result of this study was that tracheid diameter initially enlarged for 8 years, before declining toward the bark. It is possible to select provenances for a higher growth rate and for good physical (i.e., related to wood density) and anatomical (i.e., related to tracheid dimensions) wood quality attributes.

Genetic gains from 20 years of cooperative tree improvement in New Brunswick

2004 ◽  
Vol 80 (1) ◽  
pp. 127-133 ◽  
Author(s):  
Bryce McInnis ◽  
Kathleen Tosh
Keyword(s):  
New Brunswick ◽  
Picea Mariana ◽  
Pinus Banksiana ◽  
First Generation ◽  
Black Spruce ◽  
Jack Pine ◽  
Tree Improvement ◽  
Commercial Thinning ◽  
Height Gain ◽  
Rotation Age

The New Brunswick Tree Improvement Council analyzed 20-year data from plantations of unimproved and first generation improved black spruce (Picea mariana [Mill.] BSP) and jack pine (Pinus banksiana Lamb.). STAMAN, a computer model, conservatively projected an 11% merchantable volume gain at 40 years based on 20-year measurements of 36 000 trees. At age 20 years, first generation black spruce was 12% taller and 25–30% greater in total volume. Projections from over 160 000 individual measurements of height from age five to 20 years indicate that by 40 years, gains of 7–8% in height and 18–20% in total volume are likely. Ten year assessments from over 10 000 measurements of second generation black spruce indicate a 30% height gain over first generation material of the same age. For jack pine first generation material, the projections indicated a height gain of 14% and a total volume gain of over 30% at 40 years. Faster growth can provide greater volume at rotation age, a shorter rotation interval, or earlier interventions for commercial thinning. Key words: genetic gain, tree improvement, black spruce, jack pine

Wachstum und Wertleistung der Douglasie in Abhängigkeit von der Standraumgestaltung

2012 ◽  
Vol 163 (3) ◽  
pp. 96-104 ◽  
Author(s):  
Joachim Klädtke ◽  
Ulrich Kohnle ◽  
Edgar Kublin ◽  
Andreas Ehring ◽  
Hans Pretzsch ◽  
...  
Keyword(s):  
Wood Quality ◽  
Volume Growth ◽  
Static Stability ◽  
Douglas Fir ◽  
Breast Height ◽  
Monetary Analysis ◽  
Starting Conditions ◽  
Tree Number ◽  
Clear Differentiation ◽  
Further Development

Growth and value production of Douglas-fir under varying stand densities The investigation is focused on the effects of initial tree number and thinning on growth and value performance of Douglas-fir stands. Data base is a coordinated Douglas-fir spacing experiment in South Germany, started 40 years ago and comprising variants of tree numbers with 500, 1,000, 2,000 and 4,000 Douglas-firs per hectare. The treatment was performed according to a standardized experiment program. The results show that at low initial tree numbers, the diameter on breast height (DBH) of (pre)dominant trees at the beginning of the observations (with 12 m top height) is bigger than at higher initial plant numbers. Accordingly, the quotient of height (H) to DBH (as an indicator for tree's static stability) is lower. The further development of DBH and H/DBH quotient is decisively determined by stand treatment, which superimposes the effect of the initial tree number. The total volume growth shows a clear differentiation, too, the variants with initially high tree numbers appearing on top. In the monetary analysis, this ranking is reversed: despite a supposed inferior wood quality, the variants with lower initial tree numbers clearly outperform the ones with higher numbers in terms of value. From these results, the following silvicultural recommendations for Douglas-fir can be derived: the initial tree numbers should be in the range from 1,000 to 2,000 plants per hectare. On technically not accessible sites, even lower tree numbers may come into question. The strong influence of stand treatment on DBH and H/DBH development highlights the problem of postponed thinnings, for this causes growth and stability losses even under favorable starting conditions in terms of competition.

scholarly journals Diversity and Floristic Composition in the Analogous Vegetation of Indiviso, Baquerizo Moreno, Tungurahua

2021 ◽  
Author(s):  
J. Caranqui ◽  
M. Ortíz
Keyword(s):  
Relative Density ◽  
Research Study ◽  
Floristic Composition ◽  
Montane Forest ◽  
Transition Zones ◽  
Diameter At Breast Height ◽  
Breast Height ◽  
Importance Index ◽  
Palabras Clave ◽  
Number Of Individuals

This research study contributes to the knowledge of the diversity and similarity of vegetation more than 5 cm diameter at breast height (DBH); the study was carried out in the montane forest located in Tungurahua, Pillaro, Baquerizo Moreno, Indiviso (01°18’S, 78°30’W), at an altitude of 30,400 m. A transect of 1000 m² was made, divided into 5 plots of 50×4 m. The species were identified by the ESPOCH Herbarium, and the values calculated were relative density (DR) and relative dominance (DMR) to obtain the Importance Index (IV). 18 families, 29 genera, and 33 species were found, corresponding to 249 individuals, in which the largest number of individuals were accounted for by Escallonia myrtilloides (8.03%), Macleania rupestris (7.63%), Vaccinium floribundum (6.02%), Gynoxis buxifolia and Miconia bracteolata with 5.62%, Bacharis teindalensis and Blechnum loxensis with 4.82%, and Maytenus vertillata, Hypericum laricifolium, Tibouchina lepidota, Brachyotum ledifolium, Sympoccos with 4.02%; the remaining species had lower values. The reason for finding both species of shrub paramo and high montane forest is not so clear, since physiognomically the area under study was a high montane forest. Furthermore, no studies have been conducted in other transition zones, but for this reason, a high number of species of two types of vegetation is found. Keywords: analogue flowering, shrub paramo, high montane forest, indiviso. Resumen El presente trabajo contribuye al conocimiento de la diversidad y similitud de la vegetación mayor de 5 cm de diámetro a la altura del pecho (DAP); el estudio se realizó en el bosque montano localizados en provincia de Tungurahua, cantón Pillaro, parroquia Baquerizo Moreno, sector Indiviso, en las ccordenadas 01°18’S; 78°30’W, altitud 30.400 m.s.n.m. Se realizó un transecto de 1000 m², divididos en 5 subtransectos de 50×4 m. Las especies se identificaron el Herbario ESPOCH, los datos calculados fueron Densidad relativa (DR), dominancia relativa (DMR) para obtener Indice de Importancia (IV). se encontraron 18 familias, 29 géneros, 33 especies que corresponden a 249 individuos, en las cuales el mayor número de individuos cuenta Escallonia myrtilloides (8,03%), Macleania rupestris (7,63%), Vaccinium floribundum (6,02%), Gynoxis buxifolia y Miconia bracteolata con 5,62%, Bacharis teindalensis y Blechnum loxensis con 4,82%, Maytenus vertillata, Hypericum laricifolium, Tibouchina lepidota, Brachyotum ledifolium, Sympoccos quítense con 4,02%; el resto con valores inferiores. La explicación de tanto especies de páramo arbustivo y bosque montano alto no están tan claros, ya que fisionomicamente fue un bosque montano alto esta zona en estudio. Además no se han encontrado estudios en otras zonas de transición, pero por ello se encuentra un número alto de especies de dos tipos de vegetación. Palabras clave: vegetación análoga, páramo arbustivo, bosque montano, indiviso.

scholarly journals Development of stem cracks in young hybrid aspen plantations

2016 ◽  
Vol 65 (1) ◽  
pp. 16-23 ◽  
Author(s):  
Silva Šēnhofa ◽  
Mārtiņš Zeps ◽  
Arnis Gailis ◽  
Rolands Kāpostiņš ◽  
Āris Jansons
Keyword(s):  
Crack Width ◽  
Crack Formation ◽  
Fungal Infections ◽  
Wood Quality ◽  
Tree Age ◽  
Hybrid Aspen ◽  
Breast Height ◽  
Grade Scale ◽  
Clear Relation ◽  
Selection Of

Abstract Cracks expose wood to fungal infections that significantly affects wood quality, while rapid wound occlusion decreases probability of infections. Assessment of scars was done at four grade scale in three adjacent hybrid aspen trials at the age of 8-10 years in central part of Latvia three years after bark crack occurrence. Occluded wounds were found for 95% of damaged trees, regardless of tree age. Among trees that had cracks wider than 1 cm, 42% had uniformly healed bark, but 7% still had open wounds. Wound development was significantly affected by crack width and length (both p < 0.001), but had no clear relation with tree DBH (diameter at breast height) and relative DBH increment (both p > 0.05). At clonal mean level, scar grade was significantly affected by grade of crack three years earlier and clone (both p < 0.001), but mean DBH of clone had no relation (p > 0.05) to proportion of trees evaluated by any of the scar grades. The results suggest that three years after the bark crack formation most of them had successfully occluded and selection of clones with better diameter growth has no influence on development of cracks.

Hand and Machine Tree Planting in Northern Ontario

1970 ◽  
Vol 46 (6) ◽  
pp. 477-478
Author(s):  
W. C. Stevens
Keyword(s):  
Black Spruce ◽  
Jack Pine ◽  
Tree Planting ◽  
White Pine ◽  
Northern Ontario ◽  
Rock Outcrops ◽  
Important Species ◽  
Precambrian Shield ◽  
Limited Scale ◽  
Commercial Forest

Northern Ontario lies entirely in the Precambrian Shield with its many rock outcrops, sand plains, valleys and extensive lowlands.Tree planting started on a limited scale in Northern Ontario in the 1920's but it was not until the mid-fifties that the program really expanded into millions of trees.White spruce, black spruce, jack pine, red pine and white pine are the most important species planted for commercial forest products.The advent of new site preparation techniques has made possible the planting of areas that were previously by-passed.Due to the rugged conditions in Northern Ontario, tree planting by machine is still not too prevalent.For the purpose of this paper, Northern Ontario is that portion of the province lying north of the historic fur-trading route of the French and Mattawa Rivers and the Great Lakes. The area is made up entirely of Precambrian shield with many outcrops of rock, sand plains of jack pine, valleys and extensive lowlands of spruce.

scholarly journals VARIAÇÃO LONGITUDINAL E EFEITO DO ESPAÇAMENTO NA MASSA ESPECÍFICA BÁSICA DA MADEIRA DE Mimosa scabrella E Ateleia glazioveana

FLORESTA ◽  
2013 ◽  
Vol 43 (2) ◽  
pp. 327 ◽  
Author(s):  
Elder Eloy ◽  
Braulio Otomar Caron ◽  
Rômulo Trevisan ◽  
Denise Schmidt ◽  
Magda Lea Bolzan Zanon ◽  
...  
Keyword(s):  
Block Design ◽  
Wood Quality ◽  
Basic Density ◽  
Technological Characteristic ◽  
Diameter At Breast Height ◽  
Breast Height ◽  
Living Space ◽  
Randomized Complete Block Design ◽  
Axial Variation ◽  
Set Up

 Este trabalho teve como objetivo avaliar a variação longitudinal e o efeito do espaçamento de plantio na massa específica básica das árvores de Mimosa scabrella Benth e Ateleia glazioveana Baill, aos 36 meses de idade. Analisou-se um experimento instalado em delineamento de blocos completos casualizados, com três repetições. Os tratamentos foram definidos em função dos espaçamentos (2,0x1,0 m, 2,0x1,5 m, 3,0x1,0 m e 3,0x1,5 m). Foram avaliadas 72 árvores, sendo essas medidas e cubadas pelo método de Smalian. Em seguida, foram retirados discos nas posições do tronco: 0,10 m (base), 1,30 m do solo (DAP – Diâmetro a Altura do Peito), 25%, 50% e 75% da altura total da árvore, para determinação da massa específica básica. A massa específica básica em árvores de Mimosa scabrella apresentou um decréscimo até a região do DAP, seguido de acréscimo, sem tendência de estabilização com a altura. A Ateleia glazioveana apresentou uma tendência de decréscimo no sentido base-topo das árvores. Os espaçamentos influenciaram a variação da massa específica básica em árvores de Mimosa scabrella e Ateleia glazioveana, não sendo verificada uma variação sistemática positiva ou negativa em relação ao espaço vital proporcionado.Palavras-chave:  Variação axial; característica tecnológica da madeira; qualidade da madeira; espaçamento de plantio. AbstractLongitudinal variation and effect of spacing on basic density wood of Mimosa scabrella and Ateleia glazioveana. This study aimed to evaluate the variation in length and effect of spacing of the basic density of Mimosa scabrella Benth e Ateleia glazioveana Baill, trees with 36 months of age. We analyzed an experiment set up in randomized complete block design with three replications. The treatments were defined by the spacing (2.0x1.0 m, 2.0x1.5 m, 3.0x1.0 m, 3.0x1.5 m). 72 trees were evaluated, and these measures and scaled by the method of Smalian. Then, the disks were removed from the trunk positions: 0.10 m (base), 1.30 m (DAP - diameter at breast height), 25%, 50% and 75% of the total height of the tree, determining the basic density. The basic density in trees of Mimosa scabrella showed a decrease to the region of the DAP, followed by addition, without a tendency to stabilize with time. The Ateleia glazioveana showed a decreasing trend towards bottom-up tree. The spacing influenced the variation of basic density in trees of Mimosa scabrella e Ateleia glazioveana not been verified a systematic positive or negative trend in relation to the living space provided. Keywords: Axial variation; technological characteristic of wood; wood quality; planting space.

Sign in / Sign up

Export Citation Format

Share Document