scholarly journals Differentiating mature and old-growth forests in the Upper Foothills and Subalpine Subregions of west-central Alberta

2003 ◽  
Vol 79 (3) ◽  
pp. 602-612 ◽  
Author(s):  
Luigi E Morgantini ◽  
John L Kansas
Keyword(s):  
Forest Management ◽  
Growth Index ◽  
Tree Height ◽  
Tree Age ◽  
Old Growth ◽  
West Central ◽  
Decay Class ◽  
Management Area ◽  
Growth Attributes ◽  
Live Tree

Weyerhaeuser Company Ltd. is developing harvest strategies that will maintain appropriate levels of late to very late seral stages ("old growth") in its Drayton Valley Forest Management Area. This management area encompasses 490 570 ha in the Foothills and Rocky Mountain Natural Regions of west-central Alberta. In planning for future forest landscapes, Weyerhaeuser intends to maintain a range of age structures consistent with the ecological processes characteristic of each natural region and subregion. The absence of a discrete point separating mature forest from old growth means that the age at which a stand is currently identified as "old growth" and subject to special management practices is arbitrary. In a research study initiated in the summer of 2000, we seek to understand the differences in structure and composition between forests of various ages and topographic site conditions (elevation, aspect, and slope angle). Using 95 sampling plots in a 123-km2 study area in the Upper Foothills and Subalpine Natural Subregions, we quantified vegetation structure and composition for stands ranging in age from 70 to 300 years. Variables measured and analysed included live-tree height and diameter, snag density, diameter and decay class, downed woody material volume, diameter and decay class, vascular plant species richness, sapling and regeneration density, and duff depth. An old-growth index was developed for each sampled stand that took into account multiple attributes. Preliminary results indicate that specific attributes (snag basal area and density, decay stage and density of downed woody material, variation in live-tree age, and variation in live-tree height and age) separate a younger forest from a more mature one and hence may describe "old-growth" conditions. The age of onset of these old-growth attributes is variable but appears to occur between 160 and 180 years. Key factors other than stand age that contribute to or modify the development of old-growth attributes (as measured by the old-growth index) are elevation and moisture regime (as modified by site position). Further investigation is required to more accurately assess the effect of site factors on old-growth attributes. These results are now used by Weyerhaeuser to address retention of late seral stages in long-term forest planning. Key words: old growth, mature forests, old growth protection, forest management, Alberta, Weyerhaeuser, Rocky Mountains foothills

Modeling the Number of the First- and Second-Order Branches within the Live Tree Crown of Korean Larch Plantations in Northeast, China

2020 ◽  
Author(s):  
Zheng Miao ◽  
Lianjun Zhang ◽  
Faris Rafi Almay Widagdo ◽  
Lihu Dong ◽  
Fengri Li
Keyword(s):  
Negative Binomial ◽  
Small Sample Size ◽  
Sampling Strategy ◽  
Tree Height ◽  
Small Sample ◽  
Second Order ◽  
Tree Age ◽  
Count Data Models ◽  
Generalized Poisson ◽  
Live Tree

Modeling the number of branches is fundamental for simulating other branch characteristics and crown structure. In this study, a total of 77 Korean larch trees (Larix olgensis Henry) were destructively sampled from the plantations in the Northeast of China. The number of the first- and second-order branches were modeled using seven count data models, i.e., Poisson, negative binomial (i.e. NB, including NB-1, NB-2, and NB-P) and generalized Poisson (i.e. GP, including GP-1, GP-2, and GP-P) regression models. Further, the generalized linear mixed models (GLMM) were applied to those models using the sampled trees as the random effects. The results showed that (1) the Poisson regression was preferred for modeling the number of the first-order branches; (2) the GP-1 regression was considered the optimal model for the number of the second-order branches; (3) the significant predictor variables included tree height increment, branch position, relative tree size, average dominant height, and tree age; (4) the GLMM models significantly improved both modeling fitting and prediction performance; (5) the prediction accuracy of the GLMM models increased gradually with the increasing number of sample sizes; and (6) a relatively small sample size with an appropriate sampling strategy would be adequate to provide a good estimation at a specific crown section.

Occurrence of Piloderma fallax in young, rotation-age, and old-growth stands of Douglas-fir (Pseudotsuga menziesii) in the Cascade Range of Oregon, U.S.A.

2000 ◽  
Vol 78 (8) ◽  
pp. 995-1001 ◽  
Author(s):  
J E Smith ◽  
R Molina ◽  
M MP Huso ◽  
M J Larsen
Keyword(s):  
Forest Management ◽  
Pseudotsuga Menziesii ◽  
Ectomycorrhizal Fungi ◽  
Coarse Woody Debris ◽  
Woody Debris ◽  
Douglas Fir ◽  
Percent Cover ◽  
Old Growth ◽  
Decay Class ◽  
Rotation Age

Yellow mycelia and cords of Piloderma fallax (Lib.) Stalp. were more frequently observed in old-growth stands than in younger managed stands of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco). Piloderma fallax frequency and percent cover data were collected from 900 plots in three replicate stands in each of three forest age classes over 2 years in both spring and fall. Piloderma fallax is strongly associated with stand age; it occurred in 57% of plots in old-growth, 6% of rotation-age, and 1% of young stands. Presence of Piloderma fallax was related to the percent cover of coarse woody debris (CWD) in decay class 5. Piloderma fallax was approximately 2.5 times more likely to occur in a plot with CWD decay class 5 present than in plots without. The probability that it would occur in a plot increased by approximately 20% for every 10% increase in percent cover of CWD decay class 5. However, the percent cover of Piloderma fallax was not strongly related to the percent cover of CWD in decay class 5. Frequency of occurrence did not differ among sampling times. Occurrence of Piloderma fallax may indicate suitable substrate for ectomycorrhizal fungi associated with CWD and may be important in forest management for the maintenance of biodiversity and old-growth components in young managed stands.Key words: Piloderma fallax, coarse woody debris, Pseudotsuga menziesii, forest management, ectomycorrhizal fungi, biodiversity.

scholarly journals Urbanization and Decline of Old Growth Windbreak Trees on Private Homesteads: A Case Study in Ryukyu Island Villages, Japan

Forests ◽  
2020 ◽  
Vol 11 (9) ◽  
pp. 990
Author(s):  
Bixia Chen
Keyword(s):  
Spatial Distribution ◽  
Tree Height ◽  
Urban Trees ◽  
Historical Change ◽  
Urban Setting ◽  
Tree Age ◽  
Ryukyu Island ◽  
Ryukyu Archipelago ◽  
Old Growth ◽  
Minimum Diameter

Urban trees are under unprecedented pressure and competition worldwide with other land uses. Homestead windbreaks in urban areas are an important part of urban forests because of their proximity to settlements. To aid in the conservation of old-growth homestead trees in the urban setting on Ryukyu Archipelago, Japan, this article surveys the dimensions and spatial distribution of century-old trees planted as windbreaks along homestead borderlines on Ishigaki Island in the Ryukyu Archipelago and the historical change caused by urban sprawl. The homesteads studied in this article do not match the scale of a traditional Western context and usually consist of an area of less than 200 square meters on Okinawa. A combined approach consisting of field surveys and the study of aerial photos was applied to identify changes in spatial distribution of tree lines surrounding the houses in 1945, 1972 and the present. We measured the dimensions of 1659 Fukugi trees with a minimum diameter at breast height (DBH) of 5 cm. The mean tree height, mean DBH and mean estimated tree age were 7.3 m, 26.9 cm and 107.5 years, respectively. Homestead trees are not only useful as windbreaks, timber sources and musical instruments, but have also been historically resilient in the face of strong typhoons and catastrophic tsunamis in the region. Over 60% of the surveyed trees were planted on the east and north sides of homesteads as protection from typhoons and monsoonal winds in the winter. In addition to G. subelliptica, other tree species, namely Podocarpus macrophyllus and Diospyros egbert-walkeri, have been commonly used as homestead windbreaks. However, homestead windbreaks in highly urbanized regions are generally declining and have experienced fragmentation, lower tree density and shorter tree height than those in rural areas. Because of the small number of trees older than 200 years, we assume that high urbanization has jeopardized old-growth trees. The demand for settlement land dramatically increases as the population increases and household-size decreases, creating more households. Therefore, a conservation project involving multiple stakeholders must be developed to conserve old-growth trees in urban settings.

scholarly journals Spring Freeze Damage of Pecan Bloom: A Review

Horticulturae ◽  
2020 ◽  
Vol 6 (4) ◽  
pp. 82
Author(s):  
Amandeep Kaur ◽  
Louise Ferguson ◽  
Niels Maness ◽  
Becky Carroll ◽  
William Reid ◽  
...  
Keyword(s):  
Tree Height ◽  
The United States ◽  
Reproductive Organs ◽  
Tree Age ◽  
The Us ◽  
Nut Production ◽  
Freeze Damage ◽  
Terminal Buds ◽  
And Function ◽  
The Impact

Pecan is native to the United States. The US is the world’s largest pecan producer with an average yearly production of 250 to 300 million pounds; 80 percent of the world’s supply. Georgia, New Mexico, Texas, Arizona, Oklahoma, California, Louisiana, and Florida are the major US pecan producing states. Pecan trees frequently suffer from spring freeze at bud break and bloom as the buds are quite sensitive to freeze damage. This leads to poor flower and nut production. This review focuses on the impact of spring freeze during bud differentiation and flower development. Spring freeze kills the primary terminal buds, the pecan tree has a second chance for growth and flowering through secondary buds. Unfortunately, secondary buds have less bloom potential than primary buds and nut yield is reduced. Spring freeze damage depends on severity of the freeze, bud growth stage, cultivar type and tree age, tree height and tree vigor. This review discusses the impact of temperature on structure and function of male and female reproductive organs. It also summarizes carbohydrate relations as another factor that may play an important role in spring growth and transition of primary and secondary buds to flowers.

Incidence of main stem infections of lodgepole pine by western gall rust decreases with tree age

2005 ◽  
Vol 35 (6) ◽  
pp. 1314-1318 ◽  
Author(s):  
Peter V Blenis ◽  
Wuhan Li
Keyword(s):  
Pinus Contorta ◽  
Lodgepole Pine ◽  
Stem Elongation ◽  
Tree Height ◽  
Shoot Elongation ◽  
Main Stem ◽  
Tree Age ◽  
Precommercial Thinning ◽  
Two Factors ◽  
Artificial Inoculations

Infection of lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia Engelm.) by western gall rust has been shown to decrease with tree height and age, but the effects of those two factors have not been separated. Five replicate artificial inoculations were done on a total of 327 trees of different ages in two height classes. Temperature and percentage of spore germination at the height of inoculation, shoot development (stem elongation at the time of inoculation as a proportion of final shoot elongation), main stem leader length at the time of inoculation, tree height, and tree age were measured. Modeled percentages of infected trees and the number of galls per 10 cm of shoot length decreased by 85% and 88%, respectively, as tree age increased between 2 and 10 years, indicating the undesirability of early, aggressive precommercial thinning of lodgepole pine stands in areas where western gall rust is common. By controlling and (or) statistically accounting for inoculum, microclimate, and phenological factors, it was possible to demonstrate that changes in susceptibility with tree age are sufficient to account for the reduction in infection with tree height.

scholarly journals Indigenous Bamboo and Resource Management in Kenya’s Aberdare Forests and Rural Communities

2020 ◽  
Author(s):  
Chika Sasahara ◽  
Shozo Shibata
Keyword(s):  
Forest Management ◽  
Rural Communities ◽  
Public Access ◽  
National Forest ◽  
Low Density ◽  
Above Ground Biomass ◽  
Fuel Wood ◽  
Management Area ◽  
Wood Resource ◽  
Central Kenya

The Kenya Forestry Service permits rental of low-density national forest areas for use as common farmland, but public access to such areas is restricted to prevent deforestation against a background of rising demand for fuel wood. This study was conducted to clarify characteristics relating to the production of indigenous bamboo (a useful wood resource) by the approximately 23% of locals who work on common farmland in central Kenya’s Kamae forest management area, with estimation to determine above-ground biomass. The results showed that bamboo still represents 60% of such biomass, indicating sustainability in the industry.

scholarly journals Kelayakan rencana bisnis komoditas kesatuan pengelolaan hutan produksi (KPHP) DAS Belayan Provinsi Kalimantan Timur

2019 ◽  
Vol 8 (3) ◽  
pp. 194-202
Author(s):  
Rahmadi Rahmadi ◽  
Sahrul Uma ◽  
Elsy Riawati ◽  
Muhammad Ridwansyah
Keyword(s):  
Forest Management ◽  
Market Segmentation ◽  
Swot Analysis ◽  
Sustainable Forest Management ◽  
Business Plan ◽  
Carbon Trading ◽  
Management Area ◽  
Palm Sugar ◽  
The Right

KPHP Unit XXVI Belayan Watershed has a management area for production forest and protected forest that has not been optimally utilized. This study aims to develop a business plan strategy in order to optimize the resources of the KPHP Belayan watershed which is oriented towards reducing emissions to achieve sustainable forest management, improving people's welfare, and increasing income. This study use SWOT analysis to determine the right strategy in order to optimize the resources of the KPHP Belayan Watershed. The analysis results show that the commodity business (palm sugar, palm solid sugar, forest honey and kelulut honey, bamboo skewers and carbon trading) by the KPHP Belayan Watershed is financially feasible to be financed. This means that the strategy that must be carried out is to expand the market segmentation of these commodities so that these commodities can advance.   Keywords: Belayan watershed, Production forest, Sustainable forest, SWOT

scholarly journals Stand structure links up canopy processes and forest management

2009 ◽  
Vol 51 (1) ◽  
pp. 40-48
Author(s):  
Toomas Frey
Keyword(s):  
Forest Management ◽  
Stand Structure ◽  
Net Primary Production ◽  
Stand Density ◽  
Tree Height ◽  
Belowground Biomass ◽  
Unit Mass ◽  
Total Biomass ◽  
Individual Tree ◽  
Mean Values

Stand structure links up canopy processes and forest management Above- and belowground biomass and net primary production (Pn) of a maturing Norway spruce (Picea abies (L.) Karst.) forest (80 years old) established on brown soil in central Estonia were 227, 50 and 19.3 Mg ha correspondingly. Stand structure is determined mostly by mean height and stand density, used widely in forestry, but both are difficult to measure with high precision in respect of canopy processes in individual trees. However, trunk form quotient (q2) and proportion of living crown in relation to tree height are useful parameters allowing describe stand structure tree by tree. Based on 7 model trees, leaf unit mass assimilation activity and total biomass respiration per unit mass were determined graphically as mean values for the whole tree growth during 80 years of age. There are still several possible approaches not used carefully enough to integrate experimental work at instrumented towers with actual forestry measurement. Dependence of physiological characteristics on individual tree parameters is the missing link between canopy processes and forest management.

The epiphyte vegetation of the palm Socratea exorrhiza - correlations with tree size, tree age and bryophyte cover

2003 ◽  
Vol 19 (1) ◽  
pp. 81-90 ◽  
Author(s):  
Gerhard Zotz ◽  
Birgit Vollrath
Keyword(s):  
Attachment Site ◽  
Tree Height ◽  
Vertical Axis ◽  
Tree Size ◽  
Tree Age ◽  
Species Trees ◽  
Lowland Rain Forest ◽  
Vascular Epiphytes ◽  
Palm Trees ◽  
Socratea Exorrhiza

We conducted a survey of the epiphyte flora growing on the stilt palm Socratea exorrhiza in a primary lowland rain forest in Panama by means of a canopy crane. For each palm in a 0.9-ha plot, we determined diameter at breast height, tree height, per cent bryophyte cover and the number, identity and attachment site of all vascular epiphytes. The 118 palm trees hosted a total of 701 epiphytes and hemi-epiphytes, belonging to 66 species. Trees were estimated to be c. 20 y old before colonization with vascular epiphytes began. Epiphyte species were highly clumped and segregated along the vertical axis of the trunk. Sequential colonization led to an increased number of species and individuals as the tree grows. Epiphytes were associated with bryophyte patches much more than expected by chance, but no species seemed to depend upon them for establishment. The influence of tree size, age and bryophyte cover on the composition of the epiphyte community are discussed.

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