scholarly journals Revisiting the work of Fred von Althen – an update on the growth and yield of a mixed hardwood plantation in Southern Ontario

2007 ◽  
Vol 83 (2) ◽  
pp. 175-179 ◽  
Author(s):  
John H Pedlar ◽  
Saul Fraleigh ◽  
Daniel W McKenney

Dr. Fred W. von Althen, formerly of the Canadian Forest Service, established hundreds of research plantations with a focus on identifying tree species and silvicultural techniques conducive to successful hardwood afforestation in southern Ontario, Canada. Here we provide an update, using 30-year remeasurement data, on the growth and yield of one of his most productive, and compositionally unique, mixed hardwood plantations. At age 30, the plantation exhibited the following characteristics on average: 1) density of 790 stems/ha—reduced from 2222 stems/ha at time of planting through natural mortality; 2) height of 14.4 meters; 3) quadratic mean diameter of 20.1 cm; and 4) gross stand volume of 181 m3/ha. With a mean annual increment (MAI) of 6.1 m3/ha/year, this plantation exhibits one of the highest published growth rates for mixed hardwoods in temperate North America. There was considerable variation in growth and yield between the 10 hardwood species making up the stand—silver maple, white ash, and black walnut had the highest growth rates, and red and white oak the lowest. Several Carolinian species, such as catalpa and sycamore, showed good growth rates, despite the study site being located north of their published range limits. This data set provides rare information on the growth and yield of mixed hardwood plantations in Canada. Key words: growth and yield, southern Ontario, afforestation, mixed hardwoods, Carolinian species

2006 ◽  
Vol 36 (2) ◽  
pp. 495-504 ◽  
Author(s):  
John H Pedlar ◽  
Daniel W McKenney ◽  
Saul Fraleigh

We established 480 remeasurement plots in plantations originally laid out by F.W. von Althen in the 1970s and 1980s for his pioneering work on hardwood planting in southern Ontario. We used 110 of these plots to summarize the growth and yield of black walnut (Juglans nigra L.) plantations in southern Ontario. Overall, walnut growth averaged only 2.3 m3·ha–1·year–1, reflecting the less than optimal soil conditions at the majority of sites. However, good growth rates (i.e., >5 m3·ha–1·year–1) were recorded at sites with well-drained loamy soils, particularly when walnut was interplanted with other tree species. We also carried out a detailed analysis of four of the original experiments of F.W. von Althen to examine the long-term impacts of silvicultural treatments applied at an early stage in plantation development. Briefly, these analyses found (i) a significant long-term effect of controlling herbaceous competition at an early point in plantation development, although there is a suggestion that lower herbicide concentrations may be adequate in the long run, (ii) that fertilization effects, which were marginal at the time of application, were not apparent at age 32, (iii) generally better walnut growth when interplanted with other woody species, but autumn olive (Elaeagnus umbellata Thunb.), the species that stimulated the best walnut growth, grew invasively throughout the study area, thus ruling it out as a nurse species, and (iv) weak evidence that an initial spacing of 3 m × 3 m is optimal for walnut development in the absence of thinning up to age 30. This study provides rare insight into black walnut growth rates and best management practices in southern Ontario, although we recognize that the scope of these findings is limited by less than optimal soil conditions at many of the study sites.


1970 ◽  
Vol 46 (2) ◽  
pp. 139-143 ◽  
Author(s):  
F. W. Von Althen

The effects of plowing and tilling, fertilization, and chemical weed control on survival and height growth of newly planted seedlings of black locust, silver maple, white ash, white pine, and white spruce were investigated in a non-replicated study in southern Ontario. Cost-benefit relationships of treatments were computed. Plowing and tilling improved growth of all species with average increases ranging from 37 per cent for white spruce to 750 per cent for white ash. Plowing and tilling plus weed control greatly improved growth of all hardwood species and resulted in the most favourable growth-cost relationship. Fertilization improved growth of locust, ash, and maple by 200, 500, and 700 per cent respectively, but failed to increase conifer growth. Application of 12 pounds of simazine increased ash mortality by 67 per cent. White spruce was subject to severe frost heaving following complete weed control.


1991 ◽  
Vol 15 (4) ◽  
pp. 213-216 ◽  
Author(s):  
Quang V. Cao ◽  
Kenneth M. Durand

Abstract A compatible growth and yield model was developed based on remeasurement data collected from 183 plots on unthinned improved eastern cottonwood (Populus deltoides Bartr.) plantations in the lower Mississippi Delta. The Sullivan and Clutter (1972) equation form was selected for predicting cubic-foot volume yield and projecting volume from site index and initial age and basal area. Yield equations explained 97% and 94%, respectively, of the variations in total outside bark and merchantable inside bark volumes. Mean annual increment of merchantable volume culminated between 8 and 15 years, depending on site index and initial basal area. South. J. Appl. For. 15(4):213-216.


2015 ◽  
Vol 9 (13) ◽  
pp. 247 ◽  
Author(s):  
Karistsapol Nooprom ◽  
Quanchit Santipracha

Yard long bean (<em>Vigna sesquipedalis</em> L. Fruw) is one of the most popular vegetables in many countries of Southeast Asia. Especially in Thailand, it has given high productivities for export in both fresh and frozen types. Yard long bean is considered as relatively low pod yield productivity and stability because it is quite sensitive to unfavorably environmental conditions, particularly for humid tropical regions with turmoil weather. The effect of varieties on growth and yield of yard long bean was conducted at Department of Plant Science, Faculty of Natural Resources, Prince of Songkla University, Hat Yai campus, Thailand to test for yield and other horticultural characteristics of seven varieties of yard long bean. All varieties of yard long bean were well grown under Songkhla’s conditions. Randomized complete block design (RCBD) was used with four replications. The experiment was taken from February to April, 2014. The results showed that the Mae Ping, Euro, Green Arrow, Kheow Dok, and Saifa varieties exhibited good growth and high yield. The Mae Ping variety gave the highest marketable yield of 12.25 t<sup>.</sup>ha<sup>-1</sup> not significantly different (p≤0.05) from the Euro, Green Arrow, Kheow Dok, and Saifa varieties which gave the marketable yield of 15.16, 14.13, 13.51, and 13.34 t<sup>.</sup>ha<sup>-1</sup>, respectively. The Negro and Taiwan varieties were the second high yielding varieties which gave the marketable yield of 11.90 and 11.92 t<sup>.</sup>ha<sup>-1</sup>, respectively. The Euro, Kheow Dok, Saifa, and Taiwan were interesting varieties because they had pod length longer than 60 cm to meet the needs of the consumers in Songkhla province and around this area. It is concluded that the Mae Ping, Euro, Green Arrow, Kheow Dok, and Saifa varieties were the most suitable for growing under Songkhla conditions, southern Thailand due to its high growth and yield.


2021 ◽  
Author(s):  
Gaurav Joshi ◽  
Akshara Pande ◽  
Omdeep Gupta ◽  
Anoop Nautiyal ◽  
Sanjay Jasola ◽  
...  

Coronavirus disease 19 (Covid-19) is causing a dramatic impact on human life worldwide. As of June 11 2021, later one has attributed more than 174 million confirmed cases and over 3.5 million deaths globally. Nonetheless, a World Bank Group flagship report features Covid-19 induced global crisis as the strongest post-recession since World WarII. Currently, all approved therapeutics or vaccines are strictly allowed for emergency use. Hence, in the absence of pharmaceutical interventions, it is vital to analyze data set covering the growth rates of positive human cases, number of recoveries, other factors, and future strategies to manage the growth of fatal Covid-19 effectively. The Uttarakhand state of India is snuggled in the lap of the Himalayas and occupies more people than Israel, Switzerland, Hong Kong, etc. This study analyzed state Covid-19 data, fetched from an authenticated government repository using Python 3.9 from April 1, 2020, to February 28, 2021. The highest recovery rate was attributed to the hilly district Rudraprayag. The analysis also revealed that a very high doubling rate was seen during the last week of May to the first week of Jun 2020. At last, based on this blueprint, we have suggested 6-points solutions for preventing the next pandemic.


2018 ◽  
Vol 48 (9) ◽  
pp. 1007-1019 ◽  
Author(s):  
Mark Castle ◽  
Aaron Weiskittel ◽  
Robert Wagner ◽  
Mark Ducey ◽  
Jereme Frank ◽  
...  

Northern hardwood species display a variety of forms and defects that can reduce stem quality and complicate their timber management. However, for the most part, growth and yield models do not account for the influence of stem form and damage. This study determined the influence of stem form and damage on growth, survival, and projected future sawlog value among several northern commercial hardwood species. To accomplish this, hardwood trees on 112 permanent plots across three long-term research sites in Maine were assigned stem form and risk classes using a tree classification system developed in New Brunswick. A highly significant influence of stem form and risk on annualized individual-tree diameter increment and survival was found. Inclusion of these equations into a regional growth and yield model highlighted the importance of stem form and defects on long-term simulations as projected stand-level future value was significantly reduced by over 17%, on average (range of 13% to 28%), when compared with projections that did not include that tree-level information. The results highlight the importance of stem form and defects, as well as the need to account for them, in growth and yield applications that assess the forecasted value of commercially important hardwood stands.


2017 ◽  
Vol 9 (10) ◽  
pp. 145 ◽  
Author(s):  
Bibi Rouksar-Dussoyea ◽  
Ho Ming-Kang ◽  
Raja Rajeswari ◽  
Benjamin Chan Yin-Fah

This panel analysis study is conducted to examine the relationship between inflation rates (CPI) and unemployment rates (HUR) with the Gross Domestic Product growth rates (GDP), before and after the 2008 European crisis. Quarterly data for 18 consecutive years and six sample countries from Europe (Austria, France, Germany, Greece, Hungary and United Kingdom) have been considered in the panel. In order to get a more profound understanding of the impacts of the European crisis on the relationship between the variables, the panel data set has been classified into 3 separate panels, such that Panel 1 (1999Q1-2007Q4) represents before-crisis panel, Panel 2 (2008Q1-2016Q4) represents the during/after crisis panel and lastly, Panel 3 (1999Q1-2016Q4) represents the long-run panel. Panel 1 is subject to the Fixed Effects with LSDV model, whereby four out of the six countries are significant, and CPI and HUR are insignificant predictors of the GDP. Both Panel 2 and Panel 3 are subject to the Two-way Random Effects model, whereby both CPI and HUR have negative significant effect on GDP. Granger Causality test has also been carried out to determine whether causality is present among variables, based on each panel.


2011 ◽  
Vol 28 (2) ◽  
pp. 84-91 ◽  
Author(s):  
Matthew B. Russell ◽  
Aaron R. Weiskittel

Abstract An extensive statewide data set for seven conifer and eight hardwood species commonly occurring in Maine was used in the development of maximum and largest crown width equations. To establish the characteristics of open-grown trees, quantile regression was used to estimate the biological maximum crown width for a species at a given diameter. To predict crown widths of trees in forested settings, a constrained nonlinear equation was used, using the predicted maximum crown width, tree diameter, and crown ratio. The models performed well across the wide range of stand conditions present in the data set and improved predictions over the currently used crown width equations for most species (reduction of mean absolute error ranged from 1 to 23%). In general, predictions of largest crown width were not greatly improved with the inclusion of crown ratio, and there was a high amount of unexplained variation for shade-tolerant hardwood species, such as American beech (Fagus grandifolia) and sugar maple (Acer saccharum). The equations presented herein can be used in examining tree crown profiles, computing measurements of stand density, and investigating canopy dynamics for species common to the forests of Maine.


2009 ◽  
Vol 33 (4) ◽  
pp. 164-170 ◽  
Author(s):  
Daniel Leduc ◽  
Jeffery Goelz

Abstract Tree height is a critical component of a complete growth-and-yield model because it is one of the primary components used in volume calculation. To develop an equation to predict total height from dbh for longleaf pine (Pinus palustris Mill.) plantations in the West Gulf region, many different sigmoidal curve forms, weighting functions, and ways of expressing height and diameter were explored. Most of the functional forms tried produced very similar results, but ultimately the form developed by Levakovic was chosen as best. Another useful result was that scaling diameters by the quadratic mean diameter on a plot and height by the average height of dominant and codominant trees in the target stand resulted in dramatically better fits than using these variables in their raw forms.


Mathematics ◽  
2019 ◽  
Vol 7 (8) ◽  
pp. 761 ◽  
Author(s):  
Rupšys

This study focuses on the stochastic differential calculus of Itô, as an effective tool for the analysis of noise in forest growth and yield modeling. Idea of modeling state (tree size) variable in terms of univariate stochastic differential equation is exposed to a multivariate stochastic differential equation. The new developed multivariate probability density function and its marginal univariate, bivariate and trivariate distributions, and conditional univariate, bivariate and trivariate probability density functions can be applied for the modeling of tree size variables and various stand attributes such as the mean diameter, height, crown base height, crown width, volume, basal area, slenderness ratio, increments, and much more. This study introduces generalized multivariate interaction information measures based on the differential entropy to capture multivariate dependencies between state variables. The present study experimentally confirms the effectiveness of using multivariate interaction information measures to reconstruct multivariate relationships of state variables using measurements obtained from a real-world data set.


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