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Accuracy of smartphone applications in the field measurements of tree height

R eferences Andersen H-E., Reutebuch S.E., McGaughey R.J. 2006. A rigorous assessment of tree height measurements obtained using airborne LIDAR and conventional field methods. Canadian Journal of Remote Sensing , 32 (5), 355–366. Bozic M., Cavlovic J., Lukic N., Teslak K., Kos D. 2005. Efficiency of ultrasonic Vertex III hypsometer compared to the most commonly used hypsometers in Croatian forestry. Croatian Journal of Forest Engineering , 26 (2), 91–99. Bragg D.C., Frelich L.E., Leverett R.T., Blozan W., Luthringer D.J. 2011. The sine method

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Evaluating the progeny of European beech (Fagus sylvatica L.) in the early years of growth

Abstract

This research was carried out on two experimental plots located in the Rymanów and Nawojowa forest districts. In the second and fifth year after planting, at three and six years of age respectively, survival and height of 25 beech progenies of selected seed stands were measured. Furthermore, we show the effect of beech origin and growth environment (significant ‘provenance × block’ and ‘provenance × test plot’ interactions). Beeches from both experimental plots differed significantly in growth and survival and this difference increased with tree age. The highest provenance heritability was obtained for the tree height after two years of growth in Rymanów. In Nawojowa, the heritability of beech survival reached zero after five years of growth. An evaluation of the stability of beech provenances (genotypes) in terms of survival and height under the habitat conditions of our experimental plots was done using the Finlay and Wilkinson method. The beech provenances of 469- Nawojowa and 452-Lesko (regional standard) were included as a stable basis for reference. A high degree of stability and high average values for the characteristics investigated indicate high progeny quality within these stands.

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Relationships between selected tree characteristics and the properties of juvenile wood in Scots pine (Pinus sylvestris L.)

Abstract

The aim of this study was to determine relationships between selected properties of juvenile wood and characteristics of the stem and crown of Scots pine. Analyses were conducted in northern Poland on eight mature pine monocultures. Nine trees were selected in each experimental site and their stems were divided into five sections. The centers of the sections were established at a height of 1.3 m from the tree base and at points corresponding to 20, 40, 60 and 80% tree height. Samples were taken from these locations, and these samples were prepared for analyses of basic density, compressive strength along the grain and static bending, as well as the modulus of elasticity during bending. The mean height of the investigated group of trees was 26.0 m with an average diameter breast high of 33.6 cm. The mean crown depth was 7.8 m and crown diameter was 3.6 m, and the mean basic density (Qu) of juvenile pine wood was 416 kg/m3. The average compressive strength along the grain (CS) was determined to be 22.3 MPa, while static bending strength (BS) was 45.8 MPa. The recorded modulus of elasticity (MOE) was 4726 MPa.

Both in general terms and when dividing stems into sections, the wood properties correlated with tree characteristics to various degrees. All indexes were negative indicating that trees of greater dimensions produce juvenile wood of inferior quality. Properties of juvenile wood formed during various periods of tree life were mostly related to diameter breast high and crown depth. They were also correlated with tree height, but only to a limited extent. In contrast, properties of wood from the middle stem sections were significantly correlated with crown diameter.

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Tree height distribution dynamics in young naturally regenerated study plots

Abstract

Growth assessment of young stands gives the possibility of assessing forest site potential, tree species-dependent competition and developing realistic predictions for the following periods. The study is conducted in naturally regenerated broadleaves dominated stands in 2005 at Järvselja Training and Experimental Forest Center. The current study material is collected from 9 study plots established in three forest stands (regeneration felling years respectively 1996, 2000 and 2002). The study plots were re-measured 4–6 times respectively between the years of 2006 and 2012. The Weibull distribution function fit for empirical height distributions in consecutive years was tested and the estimated Weibull parameters were analysed. Results indicate that empirical height distributions of young regenerated forests do not fit well to theoretical distributions, but in many cases, empirical and theoretical distribution are similar. The Weibull distribution shape parameter was related to the maximum height and range of the height, and the scale parameter was related to the mean, quadratic mean and median height.

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The relationship between height and crown characteristics of four-year-old common birch (Betula pendula Roth)

Abstract

This paper presents the results of an analysis on characteristics of birch crowns (Betula pendula Roth) in relation to measures of the growth space occupied by a single tree at a young age. It also presents the relationships between the seedling height and certain crown characteristics. The study focused on four-year-old common birches growing in four different areas in the Elk Forest District in either fresh mixed coniferous or broadleaved forest. The measurements conducted on the chosen trees were used to calculate their crown characteristics such as crown diameter, length, height to the crown base, relative length and spread. They were also used to determine the growth characteristics of a single tree’s growth space, such as the crown area projected onto the ground, single tree space and the percentage use of unit area. Furthermore, fresh and dry leaf mass was determined. The birches growing in the fresh mixed coniferous forest reached an average height of 1.30 m, whereas in the fresh mixed broadleaved forest, the height of the trees was lower and amounted to 0.67 m. 95% of the trees had crown diameters of 0.57 m to 0.74 m in the fresh mixed coniferous forest, but only 0.19 m to 0.25 m in the fresh mixed broadleaved forest. The average lengths of the crowns in the fresh mixed coniferous and broadleaved forests amounted to 0.97 m and 0.37 m respectively. The author shows that there is a statistically significant correlation between the seedling height and the other examined characteristics. The best correlation was found between the height and the length of the crown (r = 0.9858) for birches growing in the fresh mixed coniferous forest and between the height and single tree space (r = 0.8468) for birches growing in the fresh mixed broadleaved forest.

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Forward, backward selection and variation analysis of growth traits in half-sib Larix kaempferi families

References Achere V (2004) Chloroplast and mitochondrial molecular tests identify Europe­an× Japanese larch hybrids. Theor Appl Genet 108: 1643-1649 https://doi.org/10.1007/s00122-004-1595-y Bai TD, Xu LA, Wang ZR, Lin NQ, Zhang SH (2012) Estimation of parents genetic gain by open-pollinated progeny test of seedling seed orchard of Masson pine. Forest Research 25(4): 449-455 Balocchi C, Bridgwater F, Zobel B, Jahromi S (1993) Age trends in genetic param­eters for tree height in a nonselected population of

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Early genetic evaluation of morphology and some wood properties of Tectona grandis L. clones

Abstract An early genetic evaluation of morphology and wood properties of Tectona grandis L. (teak) used two 4-yr-old trials with 36 clones x 3 blocks x 1 ramet (216 trees). Morphologic traits (breast height (DBH), heartwood (HWP), tree height) and some easily measured wood properties (specify gravity, tangential, radial and volumetric shrinkage; growth strain, and dynamic elastic modulus measured in standing tree, in logs, in green lumber and in dried lumber) were evaluated to establish clonal variations and their heritabilities. The broadsense heritability (Ĥ2 is greater than 0.3 for DBH, radial and volume shrinkage, growth strain and dynamic elastic modulus of standing trees and logs. DBH and tree height were not genetically correlated with any wood properties, although DBH was genetically correlated with tree height and the dynamic elastic modulus in dried-lumber. According with above results, the evaluation of heritability and genetic control of wood properties is limited when it is evaluated in the juvenile stage of T. grandis clones. However morphology (DBH and tree height), and two wood properties (radial and tangential shrinkage) and the dynamic elastic modulus of dried-lumber present opportunities in the heritability or genetic control values in juvenile and they can be introduced in the genetic program.

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Influence of Meteorological Factors on Needle Cast Damage in Young Scots Pine Stands

Abstract

Climate changes are expected to create favourable conditions for development and spread of diseases. Therefore, the impact of meteorological factors on needle cast damage, and relationship between degree of damage and growth of trees had been assessed in the study. Analysis was carried out in open-pollinated progeny trial of Norupe seed orchard clones, established in the spring of 2006, in Ltd. “Rīgas meži” (LLC “Riga Forests”). In this trial needle cast damage was assessed in three consecutive years using a fivegrade scale, dependent on the level of damages on current year needles. At the end of each growing season a tree height was measured. Plantation was significantly affected by infection average more than 66% of current year damaged by the disease. Significant (p<0.001) correlation was detected between the degree of needle cast damage and tree height increment as well as the tree height. Significant (p<0.001) differences in needle cast infection level as well as tree height and height increment were found also between open-pollinated families. The results suggest a potentially increasing needle cast infection due to predicted increase of temperature and precipitation, as well as the potential to select more resistant families against damages of this disease in tree breeding process.

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Characterization and mapping of QTL used in breeding of Scots pine (Pinus sylvestris L.)

Abstract

This paper reports the construction a map based on Amplified Fragment Length Polymorphic DNA (AFLP) in Scots pine (Pinus sylvestris L.). The main purpose of map construction was its application to quantitative traits loci (QTL) mapping for breeding traits economically important in Scots pine breeding program such as tree height and diameter at breast height, number of needles and their length, width, and area. Genomic DNA of needles and haploid megagamethophytes from seeds originating from a single tree were amplified with 25 AFLP primer-enzyme combinations with three or four selective nucleotides. Sixteen of them generated easily readable patterns and revealed a polymorphism. Each analyzed marker was tested for the expected 1 : 1 segregation ratio using χ2 - test and only 6 were significant with (α ≤ 0.05). The total map size equaled 291,7 cM and all markers were distributed within one linkage group. For all traits only one QTL associated with tree height (H) was detected.

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Indices of Tree Competition in Dense Spruces Stand Originated from Natural Regeneration

Abstract

This paper aims to quantify relationships between the biometric parameters of young, 15-year old spruce stands at the Experimental Site Vrchslatina. In 2011, 40 spruce trees were selected to cover four classes of bio-sociological status (dominant, co-dominant, sub-dominant, and suppressed - 10 individuals each). The trees were measured for their height increments (by recording the distances between the successive whorls) and the increments of lateral branches at all whorls. The sample trees were then cut down and discs were taken from the stem base. In the laboratory, the discs were measured for the annual ring widths using WinDendro software. We focused on detailed analyses of the relationship between the bio-sociological status of the trees on the radial and height increments. Minor differences were found in the increments in the newest lateral whorls. The ratio between height increments and lateral branch increments was found to be higher in dominant trees (height increments is two times higher than the increments on the lateral branches). Conversely, the smallest ratio was found in suppressed trees (the ratio was around 1). The ratio between tree height and diameter at the stem base, as well as the ratio between height and radial increments, was the smallest for dominant and the highest for suppressed trees. Hence, relationships between height and diameter increments (both annual and cumulative) proved to reflect competition intensity among trees.

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