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The volume of incidental wood products due to the catastrophic windfalls that occurred on the 17th of September 2017 was estimated, at national level at 460 thousand m3, of which over 200 thousand m3 were registered in the area administered by the Bihor County Forest Administration. The main objective of this paper is the study of the changes that appear in the micro-relief and of the influence of some environmental characteristics, in the beech stands (Fagus sylvatica L.) from the Forest District Sudrigiu, Management Unit U.P. VII Văratec, Bihor County Forest Administration, Romania, as an effect of windfalls. The field observations had the purpose of: determining the displaced volume (DV); breast height diameter (D1.3); height of tree (HT); average root diameter (ARD); age (A); depth of micro-depression (DM) and depth of rock / parent material (DRP). Bifactorial linear regression of the DV according to the two characteristics of the tree (D1.3) and the soil (DRP) allows an assessment of the volume of displaced soil with an accuracy of 95%. The volume of soil dislocated in the beech stands (Fagus sylvatica L.) from the Forest District Sudrigiu, Management Unit U.P. VII Văratec, Bihor County Forest Administration, Romania, evaluated with the help of the two-factor linear regression based on the basic diameter of tree D1.3 and the depth of the rock / parent material DRP and respectively the number of felled trees is between 2589.89 m3 for u.a. 100 A, partially affected and 13694.46 m3 for u.a. 104 A, affected by mass felling. To acknowledge the total volume of dislocated land and of the specific volume (m3/ ha), for the different compartments, is important for the analysis and differentiation of the variants of works necessary for the forest reconstruction of the lands affected by windfalls.

The research was performed on Norway spruce growing at the IUFRO 1964/68 experimental trial in Krynica (the Carpathians, S Poland). The growth and stability of Norway spruce were assessed taking into account the division into geographical regions proposed by Krutzsch. The height and breast height diameter were measured, on the basis of which the volume and the slenderness ratio were calculated. The stability class of each tree was also determined based on the slenderness. Significant differences were found between the Krutzsch regions for each of the analyzed traits. Spruces from region 75 (Belarus), as well as spruces from regions in the north−eastern range of the species occurrence in Poland, had above−average values of each trait. Spruces from regions in the southern part of Poland also had a good growth, but they were characterized by a large share of trees with unfavorable stability (slenderness ratio>80). The worst growth was noted for spruces from all regions located on the Scandinavian Peninsula. In the cluster analysis, four groups of Krutzsch regions were distinguished. They differed in terms of mean values of the analysed features. The best growth, tree volume and stability were characteristic for spruces from regions located in Germany, the Czech Republic, Slovakia, Poland, Belarus, Lithuania, Latvia and Russia (group C). Contrary to group D, which includes regions from the central part of the Scandinavian Peninsula, France, Tyrol and Dalmatia, the rest of spruce trees had the worst growth, low stem volume and large share of trees (>50%) classified as very unstabile., Sylwan 165 (1): 9-20

The objective of this study was to identify eucalyptus clones for the production of sawed timber based on dendrometric variables and longitudinal residual deformation (LRD), analyzing the correlation between these characteristics. 20 Eucalyptus grandis x Eucalyptus urophylla clones with 13 years of age were analyzed. The crown size, diameter at breast height (DBH) and bark thickness were measured. There was a significant difference between the clones for DBH, LRD and bark thickness. There was no significant correlation between DBH and DRL. The correlation was significant between DBH and crown size, its being possible to affirm that crown size affects the diametrical growth of trees. DBH and bark thickness were also significantly correlated, in so far as trees with a wider diameter possess thicker bark. It was possible to select clones with better potential for sawed timber production, that is to say, elevated DBH with a reduced LRD.

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.

The paper presents the results of the retrospective research on the height and diameter growth of trees in a 30−year−old white fir (Abies concolor Eng.) stand growing in the mixed broadleaved forest habitat in the Forest Experimental Station in Siemianice. The research concerned the volume and functionally related parameters including height, diameter at breast height and basal area., Sylwan 156 (12): 902-907

El objetivo del trabajo fue estudiar el efecto del sitio, el híbrido y el clon, sobre la altura total, DAP, volumen, densidad de la madera, longitud de fibras y rendimiento, de 11 clones de álamos. Se muestrearon ensayos de 10 años en dos sitios de Argentina (MD y EG). Los clones provienen de cruzamientos de P. deltoides, de cruzamientos de P. deltoides x P. nigra (P. x canadensis = P. euramericana) y P. deltoides. El sitio influyó significativamente en el crecimiento y densidad, el híbrido en la altura, densidad y longitud de fibras y los clones en todas las variables. Los árboles del sitio MD resultaron 5% más altos y 2% más densos, pero los ejemplares de EG resultaron con mayor DAP (7%) y volumen (11%). Los híbridos de P. x deltoides resultaron 4% mas altos y 4% más densos que los P. x canadensis. En longitud de fibras los híbridos P. x canadensis fueron 3% superiores. Las diferencias entre sitios y entre híbridos no resultaron tan marcadas considerando el conjunto de las propiedades. Los clones tuvieron diferente respuesta en las propiedades independientemente del cruzamiento del que derivan. Se destacaron los clones 610-31 y 564-17 (P. x deltoides) y 568-1 y Triplo (P. x canadensis)., The objective of this paper was to study site, hybrid cross and clone effects on total height, DBH, volume, wood basic density, fibre length and yield, of eleven poplars clones. 10-year-old hybrid poplar clones were sampled at two sites in Argentina (MD and EG). The material studied consisted of two poplar hybrid crosses Populus deltoides x P. deltoides and P. deltoides x P. nigra (P. x canadensis = P. x euramericana), as well as P. deltoides. Sites influenced significantly growth traits and wood density, hybrid influenced tree height, wood density and fibre length and clones influenced all variables. MD trees were 5% higher and 2% denser than EG trees, but EG trees were 7% greater in BDH and 11% more volume than the MD trees. P. deltoides and P. deltoides intra specific crosses were 4% higher and 4% denser than P. x canadensis trees. P. x canadensis fibre length was 3% higher than P. x deltoides. According to all properties, difference between site and hybrid were not very important. The properties of the clones had different responses regardless of the hybrid crosses. 610-31 and 564-17 clones (P. x deltoides) and 568-1 and Triplo (P. x canadensis) clones were distinguished., Facultad de Ciencias Agrarias y Forestales

We modelled Norway Spruce branchiness, in order to estimate wood quality of standing trees grown in monospecific even-aged stands from inventory data. We studied the whorl branches of the preformed growth unit. Their number, basal diameter and insertion angle were estimated. For delimiting crown base, we modelled heights to the first green branch, first green whorl and first dead branch. We started from a model previously established from young trees data representing the average fertility classes found in Vosges mountains. In this model, the averages of branch basal diameter and insertion angle for a whorl were computed from stem height and diameter at breast height. We aimed at: (i) modelling branch basal diameter and insertion angle variance in the whorl; (ii) verifying that the model could be applied to stands grown under conditions not accounted for in the original calibration sample (high site indices, old stands); (iii) determining the geographical area within which the model can be used without requiring any new calibration work.The branch basal diameter and insertion angle studies samples were collected in National Forest Districts Vosges (72 trees) and "Plateau Lorrain" (26 trees). The stands were selected according to their age (from plantation, if this information was available, measured on stumps otherwise) and site index (HØ), defined as the estimated dominant height at stand age 100 years. Northeastern France site classes I and II defined the high fertility modality, while site class III constituted the low fertility modality. Age modalities were: young (35 years), mature (66 and 68 years), old (95 and 133 years). After felling stem data were collected: Total height (Ht), diameter at breast height (D130), year annual height increments. In every second growth unit starting from the current year leader shoot, whorl branches were measured for basal diameter and insertion angle. Branches were declared dead when no green lateral could be found. Crown base was defined by the first green whorl (first whorl from the ground in which at least 3/4 of the branches were living), first green branch, first dead branch (no diameter constraint). Climate was defined by monthly temperature and rainfall averages computed over the 1986-1996 period. For establishing the crown base model, the sample was completed by 24 Belgian trees (4 stands, age = 48 to 82 years, HØ = 29 to 46 m) and 106 Swedish trees from 12 sampling sites distributed along a Northward gradient starting from the Southern coast (age = 61 to 152 years, HØ = 18 to 36 m). A study of the branch axis year annual area increment was carried out on 4 trees collected in a site class I stand of the "Plateau Lorrain" National Forest District. In those trees a stem analysis paralleled the measurement of branch axis year annual area increments in each branch year length increment fom the branch tip to its extremity inserted on the stem. The crown model validation sample consisted in 38 trees collected in Midi-Pyrénées administrative region (12 stands, age = 20 to 60 years, HØ = 29 to 52 m). The branch growth model validation sample was collected in Vosges National Forest District (2 stands aged 36 and 47 years, HØ = 46 and 49 m).In old trees whorls, the high variance of branch basal diameter and insertion angle led us to model separately dead and living branches. For living branches, it was shown that a same model based on Ht, D130 and stand age could estimate branches basal diameter and insertion angle in remote geographical areas. Estimates discrepancies previously observed between geographical areas could be attributed to dead branches and to the branch decay process. This was confirmed by the crown base model, in which accounting for climate was a necessity for describing all the observed variability patterns.Dead braches basal diameter and insertion angle were derived from the living branches model, by simulating branch radial growth. The study of branches year annual area increment effectively demonstrated a good correlation with stem height and radial growth, that can be seen as the baseground of the statistical correlation demonstrated between branch basal diameter and stem dimensions (Ht, D130). However branch year area increment correlated poorly to the contemporaneous stem height and radial increment, but rather to the stem height and radial increments averaged over the preceeding years.This study showed that decreasing the need for model calibration was conditionned to a better understanding of the branch mortality process and to a better explicitation of branch growth. Solutions are proposed to increase brach growth explicitation in future wood quality oriented tree simulation models.; On a cherché à modéliser la branchaison de l’Epicéa commun, issu de plantations monospécifiques équiennes, dans le but d’estimer la qualité du bois de la ressource forestière sur pied d’après les données recueillies par les gestionnaires dans le cadre des inventaires forestiers. On s’est intéressé aux branches verticillaires de l’unité de croissance préformée. On a essayé d’estimer leur nombre, leur diamètre basal et leur angle d’insertion. Au niveau du houppier on a cherché un modèle de la hauteur de la première branche verte, du premier verticille vert et de la première branche morte. On est parti d’un modèle précédemment établi pour des arbres jeunes et issus de peuplements de fertilité moyenne dans les Vosges, d’après lequel le diamètre basal moyen des branches verticillaires , l’angle d’insertion moyen et les hauteurs de base du houppier pouvaient se déduire de la donnée de la hauteur totale de la tige de son diamètre à 1,30 m et de son âge. Nos objectifs étaient : (i) essayer de modéliser la variabilité du diamètre basal et de l’angle d’insertion des branches à l’intérieur du verticille ; (ii) vérifier que le modèle peut être appliqués à des arbres choisis pour représenter des conditions de croissance non représentées dans l’échantillon initial (valeurs élevées de l’indice de fertilité, peuplements âgés) ; (iii) déterminer dans quelles limites géographique le modèle pouvait être employé sans nécessiter de calibrage.Pour l’étude du diamètre basal et de l’angle d’insertion des branches verticillaires, on a constitué un échantillon de calibrage issu des régions forestières nationales Vosges (72 arbres) et Plateau Lorrain (26 arbres). Les peuplements ont été choisis d’après leur âge (à la plantation ou à la souche) et leur indice de fertilité (HØ), qui est la hauteur dominante estimée à l’âge de 100 ans. On a défini les modalités : fertilité élevée (classes I et II) et fertilité faible (classe III), arbres jeunes (35 ans), mâtures (66 et 68 ans) et âgés (95 et 133 ans). Après abattage, on a relevé les dimensions de la tige (Ht : hauteur totale et D130 : diamètre à 1,30 m) et les accroissements en hauteur annuels. Toutes les deux unités de croissance annuelle on a mesuré les branches verticillaires pour leur diamètre basal et leur angle d’insertion. Les branches ont été notées mortes si aucun rameau latéral vert n’était détecté. Les hauteurs de base de houppier repérées ont été le premier verticille vert (hauteur du premier verticille rencontré depuis le sol avec au moins ¾ de ses branches vertes), la première branche verte, la première branche morte (hauteur du premier chicot depuis le sol). Le climat est décrit par les moyennes mensuelles de températures et précipitations non neigeuses pour la période 1986-1996. Pour la modélisation des hauteurs de base de houppiers, cet échantillon a été complété par 24 arbres belges issus de 4 peuplements (âge = 48 à 82 ans, HØ = 29 à 46 m) et 106 arbres suédois de 12 peuplements distribués du sud au nord (âge 61 à 152 ans, HØ = 18 à 36 m). Une étude fine de l’accroissement radial annuel des branches a été conduite sur 4 arbres d’un peuplement de classe de fertilité I de la région forestière nationale du Plateau Lorrain, sur lesquels on a pratiqué une analyse de tige, parallèlement à laquelle l’accroissement radial annuel a été mesuré le long de l’axe de branches verticillaire de l’extrémité insérée sur la tige jusqu’à l’apex. Pour la validation du modèle, on a utilisé un échantillon de 38 arbres de la région Midi-pyrénées (12 peuplements, Ages = 20 à 60 ans, HØ = 29 à 52 m). Pour la croissance fine des branches, l’échantillon de validation provenait de deux peuplements des Vosges (Age = 37 et 46 ans, HØ = 46 et 49 m).L’importante variance du diamètre basal des branches et de l’angle d’insertion dans le verticille des arbres âgés nous a conduit à modéliser séparément les branches vertes et les mortes. L’étude du diamètre basal des branches vertes a montré que celles-ci pouvaient être simulées dans plusieurs régions géographiques distinctes en utilisant un seul modèle dont les variables indépendantes sont Ht, D130 et âge. Les différences constatées entre régions dans la branchaison sont attribuables aux branches mortes. Cette conclusion est confimée par la modélisation de la hauteur de base du houppier pour laquelle il est possible de produire un modèle pour l’ensemble de l’échantillon à condition de prendre en compte les variables climatiques.Les caractéristiques des branches mortes ont été dérivées de celles des branches vertes en simulant leur croissance. L’étude de l’accroissement radial annuel des branches a démontré que leur croissance était effectivement très corrélée à la croissance de la tige, ce qui est à l’origine de la corrélation statistique observée à un âge donné entre le diamètre basal de la branche et la dimension de la tige (Ht, D130). L’accroissement radial des branches n’est toutefois pas corrélé avec l’accroissement de la tige contemporain, mais avec la croissance moyenne de la tige durant les années précédentes.Cette étude montre que la possibilité de réduire le besoin en recalibrage des modèles d’inventaire de la ressource sur pied est conditionnée à une meilleure compréhension du phénomène de la mortalité des branches et à l’explicitation de leur croissance. Des solutions sont proposées afin de mieux expliciter le fonctionnement de la branche dans les modèles de simulations destinés à la qualité du bois.

We modelled Norway Spruce branchiness, in order to estimate wood quality of standing trees grown in monospecific even-aged stands from inventory data. We studied the whorl branches of the preformed growth unit. Their number, basal diameter and insertion angle were estimated. For delimiting crown base, we modelled heights to the first green branch, first green whorl and first dead branch. We started from a model previously established from young trees data representing the average fertility classes found in Vosges mountains. In this model, the averages of branch basal diameter and insertion angle for a whorl were computed from stem height and diameter at breast height. We aimed at: (i) modelling branch basal diameter and insertion angle variance in the whorl; (ii) verifying that the model could be applied to stands grown under conditions not accounted for in the original calibration sample (high site indices, old stands); (iii) determining the geographical area within which the model can be used without requiring any new calibration work.The branch basal diameter and insertion angle studies samples were collected in National Forest Districts Vosges (72 trees) and "Plateau Lorrain" (26 trees). The stands were selected according to their age (from plantation, if this information was available, measured on stumps otherwise) and site index (HØ), defined as the estimated dominant height at stand age 100 years. Northeastern France site classes I and II defined the high fertility modality, while site class III constituted the low fertility modality. Age modalities were: young (35 years), mature (66 and 68 years), old (95 and 133 years). After felling stem data were collected: Total height (Ht), diameter at breast height (D130), year annual height increments. In every second growth unit starting from the current year leader shoot, whorl branches were measured for basal diameter and insertion angle. Branches were declared dead when no green lateral could be found. Crown base was defined by the first green whorl (first whorl from the ground in which at least 3/4 of the branches were living), first green branch, first dead branch (no diameter constraint). Climate was defined by monthly temperature and rainfall averages computed over the 1986-1996 period. For establishing the crown base model, the sample was completed by 24 Belgian trees (4 stands, age = 48 to 82 years, HØ = 29 to 46 m) and 106 Swedish trees from 12 sampling sites distributed along a Northward gradient starting from the Southern coast (age = 61 to 152 years, HØ = 18 to 36 m). A study of the branch axis year annual area increment was carried out on 4 trees collected in a site class I stand of the "Plateau Lorrain" National Forest District. In those trees a stem analysis paralleled the measurement of branch axis year annual area increments in each branch year length increment fom the branch tip to its extremity inserted on the stem. The crown model validation sample consisted in 38 trees collected in Midi-Pyrénées administrative region (12 stands, age = 20 to 60 years, HØ = 29 to 52 m). The branch growth model validation sample was collected in Vosges National Forest District (2 stands aged 36 and 47 years, HØ = 46 and 49 m).In old trees whorls, the high variance of branch basal diameter and insertion angle led us to model separately dead and living branches. For living branches, it was shown that a same model based on Ht, D130 and stand age could estimate branches basal diameter and insertion angle in remote geographical areas. Estimates discrepancies previously observed between geographical areas could be attributed to dead branches and to the branch decay process. This was confirmed by the crown base model, in which accounting for climate was a necessity for describing all the observed variability patterns.Dead braches basal diameter and insertion angle were derived from the living branches model, by simulating branch radial growth. The study of branches year annual area increment effectively demonstrated a good correlation with stem height and radial growth, that can be seen as the baseground of the statistical correlation demonstrated between branch basal diameter and stem dimensions (Ht, D130). However branch year area increment correlated poorly to the contemporaneous stem height and radial increment, but rather to the stem height and radial increments averaged over the preceeding years.This study showed that decreasing the need for model calibration was conditionned to a better understanding of the branch mortality process and to a better explicitation of branch growth. Solutions are proposed to increase brach growth explicitation in future wood quality oriented tree simulation models.; On a cherché à modéliser la branchaison de l’Epicéa commun, issu de plantations monospécifiques équiennes, dans le but d’estimer la qualité du bois de la ressource forestière sur pied d’après les données recueillies par les gestionnaires dans le cadre des inventaires forestiers. On s’est intéressé aux branches verticillaires de l’unité de croissance préformée. On a essayé d’estimer leur nombre, leur diamètre basal et leur angle d’insertion. Au niveau du houppier on a cherché un modèle de la hauteur de la première branche verte, du premier verticille vert et de la première branche morte. On est parti d’un modèle précédemment établi pour des arbres jeunes et issus de peuplements de fertilité moyenne dans les Vosges, d’après lequel le diamètre basal moyen des branches verticillaires , l’angle d’insertion moyen et les hauteurs de base du houppier pouvaient se déduire de la donnée de la hauteur totale de la tige de son diamètre à 1,30 m et de son âge. Nos objectifs étaient : (i) essayer de modéliser la variabilité du diamètre basal et de l’angle d’insertion des branches à l’intérieur du verticille ; (ii) vérifier que le modèle peut être appliqués à des arbres choisis pour représenter des conditions de croissance non représentées dans l’échantillon initial (valeurs élevées de l’indice de fertilité, peuplements âgés) ; (iii) déterminer dans quelles limites géographique le modèle pouvait être employé sans nécessiter de calibrage.Pour l’étude du diamètre basal et de l’angle d’insertion des branches verticillaires, on a constitué un échantillon de calibrage issu des régions forestières nationales Vosges (72 arbres) et Plateau Lorrain (26 arbres). Les peuplements ont été choisis d’après leur âge (à la plantation ou à la souche) et leur indice de fertilité (HØ), qui est la hauteur dominante estimée à l’âge de 100 ans. On a défini les modalités : fertilité élevée (classes I et II) et fertilité faible (classe III), arbres jeunes (35 ans), mâtures (66 et 68 ans) et âgés (95 et 133 ans). Après abattage, on a relevé les dimensions de la tige (Ht : hauteur totale et D130 : diamètre à 1,30 m) et les accroissements en hauteur annuels. Toutes les deux unités de croissance annuelle on a mesuré les branches verticillaires pour leur diamètre basal et leur angle d’insertion. Les branches ont été notées mortes si aucun rameau latéral vert n’était détecté. Les hauteurs de base de houppier repérées ont été le premier verticille vert (hauteur du premier verticille rencontré depuis le sol avec au moins ¾ de ses branches vertes), la première branche verte, la première branche morte (hauteur du premier chicot depuis le sol). Le climat est décrit par les moyennes mensuelles de températures et précipitations non neigeuses pour la période 1986-1996. Pour la modélisation des hauteurs de base de houppiers, cet échantillon a été complété par 24 arbres belges issus de 4 peuplements (âge = 48 à 82 ans, HØ = 29 à 46 m) et 106 arbres suédois de 12 peuplements distribués du sud au nord (âge 61 à 152 ans, HØ = 18 à 36 m). Une étude fine de l’accroissement radial annuel des branches a été conduite sur 4 arbres d’un peuplement de classe de fertilité I de la région forestière nationale du Plateau Lorrain, sur lesquels on a pratiqué une analyse de tige, parallèlement à laquelle l’accroissement radial annuel a été mesuré le long de l’axe de branches verticillaire de l’extrémité insérée sur la tige jusqu’à l’apex. Pour la validation du modèle, on a utilisé un échantillon de 38 arbres de la région Midi-pyrénées (12 peuplements, Ages = 20 à 60 ans, HØ = 29 à 52 m). Pour la croissance fine des branches, l’échantillon de validation provenait de deux peuplements des Vosges (Age = 37 et 46 ans, HØ = 46 et 49 m).L’importante variance du diamètre basal des branches et de l’angle d’insertion dans le verticille des arbres âgés nous a conduit à modéliser séparément les branches vertes et les mortes. L’étude du diamètre basal des branches vertes a montré que celles-ci pouvaient être simulées dans plusieurs régions géographiques distinctes en utilisant un seul modèle dont les variables indépendantes sont Ht, D130 et âge. Les différences constatées entre régions dans la branchaison sont attribuables aux branches mortes. Cette conclusion est confimée par la modélisation de la hauteur de base du houppier pour laquelle il est possible de produire un modèle pour l’ensemble de l’échantillon à condition de prendre en compte les variables climatiques.Les caractéristiques des branches mortes ont été dérivées de celles des branches vertes en simulant leur croissance. L’étude de l’accroissement radial annuel des branches a démontré que leur croissance était effectivement très corrélée à la croissance de la tige, ce qui est à l’origine de la corrélation statistique observée à un âge donné entre le diamètre basal de la branche et la dimension de la tige (Ht, D130). L’accroissement radial des branches n’est toutefois pas corrélé avec l’accroissement de la tige contemporain, mais avec la croissance moyenne de la tige durant les années précédentes.Cette étude montre que la possibilité de réduire le besoin en recalibrage des modèles d’inventaire de la ressource sur pied est conditionnée à une meilleure compréhension du phénomène de la mortalité des branches et à l’explicitation de leur croissance. Des solutions sont proposées afin de mieux expliciter le fonctionnement de la branche dans les modèles de simulations destinés à la qualité du bois.

Tesis (M. Sc) -- CATIE, Turrialba (Costa Rica), 2004 110 páginas 4 ilus. 31 tab. Referencias 103-110 En el año 2003, en el bosque húmedo tropical secundario Florencia, San Carlos, Costa Rica, se realizó una evaluación de 14 parcelas permanentes (PPM) de 40 m x 60 m (0.24 ha). El primer componente del estudio pretendió caracterizar la dinámica del rodal en términos de la composición florística y riqueza de especies, así como la dinámica de especies individuales y el crecimiento en diámetro, comparando los dos tipos de bosque. El segundo componente del estudio pretendió caracterizar el efecto del tratamiento silvicultural sobre la dinámica del rodal y de especies individuales así como el crecimiento en diámetro. Los resultados indican que hubo efecto del tratamiento sobre la dinámica poblacional y el incremento en diámetro a nivel de rodal tratado. Sin embargo, no fue significativo el efecto sobre el crecimiento de los árboles para la futura cosecha. Se concluye que ese tipo de intervención silvicultural en bosques secundarios en la tercera etapa de la sucesión no es recomendable por los altos costos de la intervención que no son recompensados por el aumento en el crecimiento diamétrico de árboles de especies. In 2003, 14 permanent sample plots (PSP) of 40 m x 60 m each (0.24 ha) were measured in the tropical secondary forest Florencia, San Carlos, Costa Rica. The first component of the study sought to characterize the stand dynamics in terMON of floristic composition and species richness, as well as the dynamics of individual species and diameter growth, comparing the two forest types. The second component aimed at characterizing the effect of the silvicultural treatment on stand dynamics, the dynamics of individual species, and diameter growth. The results reveal the effect of the silvicultural treatment on population dynamics and diameter growth at the level of the treated stand. However, the effect was not significant on the growth of future crop trees. It is concluded that this type of silvicultural intervention in secondary forests of the third succession phase is not recommendable in view of the high costs that are not compensated for by the increase in diameter growth of the commercial tree species.

Tesis (M. Sc) -- CATIE, Turrialba (Costa Rica), 2003 24 Ilustraciones. 13 Tablas Referencias de las páginas 51-55 Este estudio analizó la influencia de la iluminación de la copa sobre el incremento en DAP y área basal de Pentaclethra macroloba y Goethalsia meiantha, y fue llevado a cabo en bosques húmedos tropicales de los sectores Puerto Viejo de Sarapiquí y Palmitas (Costa Rica) en parcelas permanentes de muestreo de FUNDECOR (bosque no inundable) y de PORTICO S.A. (bosque inundable). La influencia de la iluminación de copa fue significativa en los árboles de Goethalsia meiantha, pero, en los bosques no inundables, no fue significativa para los árboles de Pentaclethra macroloba. En ambos casos, se encontró otras variables más importantes que la iluminación de copa: forma de copa, diámetro de copa, DAP, posición topográfica, infestación de lianas y densidad circundante del bosque. Se discute las implicaciones para la silvicultura de los bosques tropicales húmedos. This study analyzed the influence of the crown illumination on the diameter increments and basal area of Pentaclethra macroloba and Goethalsia meiantha and was carried out in tropical moist forests of the sectors Puerto Viejo de Sarapiquí y Palmitas (Costa Rica) in permanent sample plots in logged forest of FUNDECOR (nonfloodable forest) and PORTICO S.A. (floodable forest). The influence of crow ilumination was significant in the trees of Goethalsia meiantha, but it was not significant in the trees of Pentaclethra macroloba. In both cases, there were other attributes more important than crown illumination, such as crown form, crown diameter, DBH, the topographic position, presence of lianas and the surrounding forest density. The implications for the silviculture of the tropical moist forests are discussed.

The purpose of this study was to compare the Weibull distributions estimated for the entire growing stock of a stand and separately for Scots pine ( L.) and Norway spruce ( (L.) H. Karst.) in describing the basal area diameter distributions in mixed stands. The material for this study was obtained by measuring 553 stands located in eastern Finland. The parameters of the Weibull distribution were estimated using the method of maximum likelihood. The models for these parameters were derived using regression analysis. Also, some parameter models from previous studies were compared with the measured distribution. The obtained distributions were compared using the diameter sums of the entire growing stock, diameter sums by tree species and of the sawtimber part of the growing stock. The results showed that far more accurate results were obtained when the distributions were formed using parameter models separately for the different tree species than when using parameter models for the entire growing stock. This was already true when considering the entire growing stock of the stand and especially when the results were examined by tree species. When the models for the entire growing stock were applied by tree species in relation to basal areas, the results obtained were overestimates for Norway spruce and underestimates for Scots pine. The models from earlier studies, where parameter models were estimated separately for tree species from the National Forest Inventory data, showed good fits also in regard to the data of this study.Pinus sylvestrisPicea abies

The objective of this paper was to study site, hybrid cross and clone effects on total height, DBH, volume, wood basic density, fibre length and yield, of eleven poplars clones. 10-year-old hybrid poplar clones were sampled at two sites in Argentina (MD and EG). The material studied consisted of two poplar hybrid crosses Populus deltoides x P. deltoides and P. deltoides x P. nigra (P. x canadensis = P. x euramericana), as well as P. deltoides. Sites influenced significantly growth traits and wood density, hybrid influenced tree height, wood density and fibre length and clones influenced all variables. MD trees were 5% higher and 2% denser than EG trees, but EG trees were 7% greater in BDH and 11% more volume than the MD trees. P. deltoides and P. deltoides intra specific crosses were 4% higher and 4% denser than P. x canadensis trees. P. x canadensis fibre length was 3% higher than P. x deltoides. According to all properties, difference between site and hybrid were not very important. The properties of the clones had different responses regardless of the hybrid crosses. 610-31 and 564-17 clones (P. x deltoides) and 568-1 and Triplo (P. x canadensis) clones were distinguished., Facultad de Ciencias Agrarias y Forestales