Natural regeneration of jack pine on clay soils following harvesting and site preparation: Seventh-year results

2010 ◽  
Vol 86 (4) ◽  
pp. 423-433 ◽  
Author(s):  
Martin Béland ◽  
Sébastien Calmels ◽  
Yves Bergeron

This study examines the operational feasibility of six treatments to regenerate jack pine (Pinus banksiana Lamb.) naturally without fire following harvesting on clay soils in the southeastern boreal forest of Quebec. The experiment is a randomized complete block design. Techniques used were a final cutting in 1993 with manual on-site delimbing or roadside delimbing combined with three methods of soil scarification (WadellTM, La TaupeTM and a control) performed in the Spring of 1994 compared to an adjacent jack pine plantation established in 1994 after Wadell scarification. Seven growing seasons later, the present article compares stand composition, competing vegetation, regeneration and growth of jack pine between the different treatments as well as an adjacent plantation. Natural regeneration produced mixed stands with an adequate 52% average jack pine stocking. Roadside and on-site delimbing produced similar jack pine stocking on average. However, the plantation showed 83% stocking and better performance than natural regeneration in terms of height (2.48 m vs. 1.7 m for natural regeneration), diameter (41 mm vs. 22 mm for natural regeneration) and jack pine dominance. Therefore, if natural regeneration is desired, roadside delimbing is to be recommended since it provides sufficient seed and does avoid early jack pine growth reductions caused by slash. On clay soils, scarification seems to have been optional. Nevertheless, it slightly increased seedling growth and in this way, the treatment combining road-side delimbing and an extensive scarification can be an effective jack pine natural regeneration treatment.Key words: Pinus banksiana Lamb., natural regeneration, stocking coefficient, delimbing, scarification, boreal mixed wood, seedlings

2017 ◽  
Vol 52 (5) ◽  
pp. 311-318
Author(s):  
Renata Gimenez Sampaio Zocche ◽  
Suziane Antes Jacobs ◽  
Norton Victor Sampaio ◽  
Velci Queiróz de Souza ◽  
Ivan Ricardo Carvalho ◽  
...  

Abstract: The objective of this work was to characterize 'Cabernet Sauvignon' wines made from grapes cultivated in the region of Bagé, RS, Brazil, during three crop seasons. A randomized complete block design was carried out with three treatments and three replicates.The evaluations were performed for the 2004, 2007, and 2008 growing seasons. 'Cabernet Sauvignon' wines of the 2004, 2008, and 2009 harvests differed for the following parameters: density, alcoholic content, total acidity, pH, reducing sugars, OD 420, 520, and 620, color intensity, total anthocyanins, total polyphenols, sodium, calcium, magnesium, manganese, copper, iron, rubidium, phosphorus, methanol, propanol, 2-methyl-l-propanol, 2, 3 - methyl-l-butanol, and sum of alcohols. 'Cabernet Sauvignon' has potential to be produced in the Bagé region, and to help it to become a wine growing region in Brazil.


2000 ◽  
Vol 17 (3) ◽  
pp. 100-109 ◽  
Author(s):  
D.G. Pitt ◽  
Andrée E. Morneault ◽  
Philip Bunce ◽  
F.Wayne Bell

Abstract Five years of data on vegetation dynamics and succession are provided for six operational release treatments applied to three 2- to 4-yr-old jack pine (Pinus banksiana Lamb.) plantations in central Ontario. Treatments included 3 yr of annual noncrop vegetation removal, conventional aerial spray with glyphosate (1.42 kg ae/ha), ground application of glyphosate with a mist blower, basal-bark application of triclopyr, motor-manual cutting (brush saw), and no treatment. Conventional aerial spraying and annual removal resulted in the greatest jack pine crop growth, with trees exceeding 90% crown closure, 7 cm in groundline diameter, and 3 m in height (stem volume index = 5.1 dm³) after 5 growing seasons. The cover of herbaceous plants was highest (30–50%) in the aerial spray plots during the observation period. Deciduous tree, shrub, and fern species remained well represented on these plots, although total cover and height were low (≤ 35% and 1 m, respectively). Mist-blower and brush-saw plots contained mid-sized pine (3.5 dm³) with 69% crown closure. In contrast, untreated and basal-bark plots contained the smallest pine (2.3 dm3 and 31% crown closure), likely caused by heavy competition and herbicide damage, respectively. On mist-blower and basal-bark plots, good height growth was observed on untreated deciduous trees; low-shrub and fern cover remained high (46 and 30%, respectively); and herbaceous cover increased gradually to 22%. On brush-saw plots, recovery of woody cover was rapid, but height growth was relatively slow. Deciduous trees and tall shrubs dominated untreated sites (> 70% cover) by the end of the fifth growing season. Successional trends suggest that aerial spray and annual removal treatments will produce pure jack pine stands at maturity; mist blower, basal bark, and brush-saw treatments may produce mixedwood stands; and untreated plots will likely be dominated by hardwoods. North. J. Appl. For. 17(3):100–109.


1988 ◽  
Vol 64 (4) ◽  
pp. 315-319 ◽  
Author(s):  
Z. Chrosciewicz

An experimental burn in conjunction with a seed-tree system was successful in regenerating jack pine (Pinus banksiana Lamb.) on a fresh to somewhat moist upland, loamy till, cutover site in central Saskatchewan. About 20 well-formed, uniformly spaced seed trees per hectare were left standing during timber harvest. The ignition of logging slash was carried out under preselected weather and fuel conditions so that favorable seedbeds and adequate seed dispersal from the seed trees were produced. Four growing seasons after burning, jack pine stocking by 4-m2 quadrats was 90% with 12 195 seedlings/ha. Aspen (Populus tremuloides Michx.), to a lesser degree black spruce (Picea mariana [Mill.] B.S.P.), and other companion tree species also regenerated with the pine. Various seedbed and regeneration characteristics as well as height growth rates are discussed. Key words: Pinus banksiana, slash burning, seed-tree system, forest regeneration, growth rates, central Saskatchewan.


2017 ◽  
Vol 26 (6) ◽  
pp. 478 ◽  
Author(s):  
Maria Sharpe ◽  
Hyejin Hwang ◽  
David Schroeder ◽  
Soung Ryoul Ryu ◽  
Victor J. Lieffers

This study documents cone opening and natural regeneration of jack pine (Pinus banksiana Lamb.) after burning live and dead stands similar to those killed by the mountain pine beetle (Dendroctonus ponderosae). Trees were killed by girdling in May and were burned in late July, 26 months later. Pairs of live and dead plots were simultaneously burned using three types of fire: surface, intermittent crown and continuous crown fires. Each type of fire was replicated three times; the nine pairs of burns were completed in a 4-day period. After fire, more cones were opened on dead trees than live trees. On dead trees, there was cone opening even when fire charred only the lower part of the bole. Three years after burning, dead stands with continuous crown fires had some of the densest regeneration and the highest rates of stocking. Across all burns in this study, seedling regeneration was best in shallow residual duff and in the more intensely burned plots. Without burning, there was virtually no regeneration 5 years after mortality. The results also show that burning, especially under continuous crown fire, could be used to promote regeneration in dead stands.


1981 ◽  
Vol 57 (5) ◽  
pp. 208-211 ◽  
Author(s):  
I. K. Morrison ◽  
N. W. Foster ◽  
H. S. D. Swan

Results are reported from the third in a series of three industry-sponsored forest fertilization field trials established in an approximately 55-year-old jack pine (Pinus banksiana Lamb.) stand in the Dryden-Sioux Lookout area of northwestern Ontario. The experiment was of randomized block design and tested various combinations of N plus P and N plus K. The experiment was unique in that fertilizers were applied in the fall on approximately 5 cm of early snow. Significant increases over control for several parameters after both five and ten years were noted for several treatments. Best response in relation to total volume increment over ten years was to N at 112 kg/ha plus K at 93 kg/ha where 21.72 m3/ha of extra wood was produced.


Author(s):  
Hamada Amer ◽  
Mohamed Z. Dakroury ◽  
Ibrahim S. El Basyoni ◽  
Hanaa M. Abouzied

This study was conducted to assess the effect of soil salinity on leaf area (LA), the number of days to flowering (DF), plant height (PH), and grain yield. Overall, 60 wheat genotypes were used, including 49 CIMMYT elite lines and 11 commercially grown Egyptian wheat cultivars. During two growing seasons (2017 and 2018), the genotypes were grown in non-saline (S0) and saline (S1) soils. A randomized complete block design with three replicates was used in a split-plot arrangement. Salinity levels were randomly assigned to the main plots, while genotypes were randomly assigned to the subplots. The obtained results showed that the saline soil adversely affected the evaluated genotypes. Furthermore, a highly significant effect of genotypes × salinity was observed on grain yield and its attributed traits. Based on salinity indices results, some of the imported wheat genotypes outperformed the Egyptian cultivars in grain yield under salinity stress conditions. The results further indicated that Sakha-93, C-31, and C-40 were the most salt-tolerant genotypes. The best performing line among the CIMMYT lines was C-31, which recorded the highest grain yield under none-saline and saline soil in the two seasons of study.


Author(s):  
Cahit Erdoğan

This study was carried out in Amik plain, Turkey in 2013 and 2014 growing seasons to determine some morphological and agricultural characteristics of four cowpea varieties registered for dry grain in Turkey. The experiment was laid out in a randomized complete block design with three replications. According to the results, the highest plant height (221.8 cm) and the highest first pod height (43.6 cm) was obtained from the variety Sırma; the highest number of branch per plant (4.0), the highest pod length (14.9 cm), the highest number of pod per plant (19.8), the highest grain number per plant (113.5), the highest hundred grain weight (22.2 g), and the highest grain yield (275.2 kg/da) from the variety Amazon; the highest number of grain per pod (6.2) and the highest harvest index (39%) from the variety Karagöz. Furthermore, it was determined from the correlation analysis that there were both positive and negative correlations between some characteristics. Considering grain yield, the variety Amazon can be recommended to the cowpea growers in Amik plain, Turkey.


2017 ◽  
Vol 52 (6) ◽  
pp. 455-463 ◽  
Author(s):  
Inocencio Junior de Oliveira ◽  
André Luiz Atroch ◽  
Miguel Costa Dias ◽  
Lauro José Guimarães ◽  
Paulo Evaristo de Oliveira Guimarães

Abstract: The objective of this work was to evaluate corn cultivars grown in the state of Amazonas, Brazil, which simultaneously show high grain yield, adaptability, and stability. The trials were carried out in seven environments in the state of Amazonas, in a randomized complete block design, with two replicates. The grain yield of 30 corn cultivars was evaluated in four growing seasons, from 2011/2012 to 2014/2015. The genetic parameters were estimated by the REML/Blup methodology. The selection for adaptability and stability was based on the predicted genetic value and on the harmonic mean of the relative performance of the genetic values. Despite the existence of genotype x environment interaction, cultivars with high adaptability and stability were identified. Iranduba - lowland, in 2011/2012 and 2014/2015 - and Rio Preto da Eva - upland, in 2012/2013 - stood out as favorable environments, while Iranduba - upland, in 2011/2012 and 2012/2013 - and Manaus - upland, in 2012/2013 and 2013/2014 - were classified as unfavorable environments. The single-cross hybrid BRS 1055 showed productive superiority and high stability in this region. The Sint 10771, Sint 10781, and Sint 10699 synthetic varieties showed high adaptability. BRS Caimbé shows specific adaptability to cropping in upland environments of the state of Amazonas, Brazil.


2019 ◽  
Vol 2019 ◽  
pp. 1-7 ◽  
Author(s):  
Fiseha Baraki ◽  
Muez Berhe

Ethiopia is one of the famous and major producers of sesame in sub-Saharan Africa, and Ethiopian sesame is among the highest quality in the world. The experiment was conducted in Northern Ethiopia for three growing seasons (2013–2015) under a rain fed condition with the objective of identifying high-yielding genotypes and their agronomic traits. The experiment consisted of twelve genotypes laid down in randomized complete block design with three replications. The genotype, year, and genotype × year interaction components showed statistically highly significant variation (p<0.001) for most of the agronomic traits which clearly confirms the presence of genotype × year interaction in this study. The highest combined mean grain yield (906.3 kg/ha) was obtained from Hirhir followed by Serkamo white (756.5 kg/ha), and from the three growing seasons, the highest grain yield (1161.5 kg/ha) was recorded from Hirhir grown in the second growing season (2014). The growing seasons were different from one another in allowing the genotypes to have a different performance, and all of the agronomic traits, except thousand seed weight, were statistically different across the three growing seasons. In the ordination of the genotypes and agronomic traits, PCA1, which accounted for 38.3% of the variation, was positively associated with grain yield, branches per plant, length of the pod-bearing zone, plant height, number of pods per plant, number of seeds per pod, and thousand seed weight. On the contrary, PCA2, which accounted for 19.7% of the variation, was positively associated with days to 50% flowering and days to 50% maturity.


2015 ◽  
Vol 91 (01) ◽  
pp. 52-59 ◽  
Author(s):  
Rongzhou Man ◽  
G. Blake MacDonald

The conventional plantation approach to regenerating jack pine (Pinus banksiana) after harvesting maximizes pine growth but may reduce wood quality. In this study we examined growth of planted jack pine and natural regeneration after herbicide spraying and partial cutting treatments on a boreal mixedwood site in northeastern Ontario. Treatments were pre-harvest aerial spray, post-harvest ground spray in strips (partial spray), partial cut, and post-harvest aerial broadcast spray; an untreated reference stand was used for comparison. Pre-harvest spray was as effective as partial cutting and post-harvest broadcast spray in suppressing trembling aspen regeneration and providing adequate light for survival and growth of planted jack pine. Ten years after planting, mortality and growth of pines in the pre-harvest treatment were comparable to those in the partial and broadcast spray treatments. Due to vigorous growth of broadleaf species [mostly red maple; (Acer rubrum)], and shade from the residual overstory, jack pine was smallest in the partial cut treatment; however, based on branch size, branch-free stem length and stem taper, wood quality was highest in this treatment. Considering factors important to forest managers such as growth and quality of planted jack pine, treatment costs, and proportion of the harvested blocks allocated to conifer production, the preferred treatment was pre-harvest spray.


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