La transformation et l'utilisation du bois de peuplier

in Le Peuplier en Wallonie (2003)

The poplar wood has been largely used (frame – carpentry packing – paper pulp – sabot manufacture – furniture – rotary peeling for panels and packaging). Some uses of the past were progressively abandoned ... [more ▼]

The poplar wood has been largely used (frame – carpentry packing – paper pulp – sabot manufacture – furniture – rotary peeling for panels and packaging). Some uses of the past were progressively abandoned for tropical species or softwood. But the poplar is now largely used for the rotary peeling process, where its characteristics are appropriated and appreciated. The products not suitable for rotary peeling are used for packaging and ships for panel industry. In the past inside the important wooded areas was never considered as an valuable species while it was used in areas of small forests. Indeed for products with little added value the transportation costs become paramount and in such a case the production of poplars outside large forests become an advantage. A better knowledge of its capabilities during the various stages of its transformation and of its behaviour under various treatments has made it possible to look for new markets so as to enlarge the possibility of use. [less ▲]

Propriétés des merrains affinés dans une solution d’enzymes naturels et destinés à la tonnellerie

in Annals of Forest Science : a Multidisciplinary and International Journal (2003), 60

Properties of shooks ageing by a treatment in a solution of natural enzymes. A speeding up of the ageing of shooks is possible by a treatment with a solution of natural enzymes. However its repercussion ... [more ▼]

Properties of shooks ageing by a treatment in a solution of natural enzymes. A speeding up of the ageing of shooks is possible by a treatment with a solution of natural enzymes. However its repercussion on physical, mechanical characteristics of wood and on its absorption potential of an hydro-alcoholic solution must be tested. Normalized samples have been extracted from 150 shooks selected on a ring width criteria from three cooperages located on different supplying area in France. The three factors cooperage, ring width class and treatment are used for statistical analysis. The cooperage factor, reflection of the supply area of each of them, affect the young modulus and the modulus of rupture in static bending but not the other characteristics. The improvement of the wood properties is closely linked to the ring width increaseof the samples. The enzymatic treatment has no significant effect on physical and mechanical characteristics of oak wood, except on the hardness and, to a lesser extent, on the absorption potential. Considering the absence of negative effect on characteristics of shooks and the positive contribution of enzymatic treatment on their ageing, this treatment could bring a very interesting economical alternative permitting to avoid long lasting storage of the shooks before assembly. [less ▲]

Etude de l'effet d'un stimulus gravitationnel induit artificiellement sur la formation du bois de tension et du bois opposé dans de jeunes pousses de peuplier (Populus euramericana cv "Ghoy"

Doctoral thesis (2002)

The tension wood of arborescent dicotyledons can be distinguished by its anatomical, chemical, physical and mechanical characteristics which give to it a specific behavior. In its development interfere ... [more ▼]

The tension wood of arborescent dicotyledons can be distinguished by its anatomical, chemical, physical and mechanical characteristics which give to it a specific behavior. In its development interfere complex mechanisms able to perceive endogenous and exogenous stimuli acting on the cambial zone during the new cell differentiation and maturation. Its particular distribution in the shoot induces a dissymetrical distribution of growth stresses capable to modify their orientation. The supporting thesis of this study maintains the idea of a quantitative responses of the young shoots of poplar which develop under controlled conditions, as a reaction to a gravitational stimulus artificially induced. To demonstrate this, the experimental approach consisted on one hand, to determine the reaction induced by the stimulus in the wood structure. On the other hand, to attempt to establish the existence of a modulation of the shoots reaction in regard of the duration and of the intensity of the stimulus application, while applying increasing levels of these parameters. The anatomical observations were based on microscopic cross sections taken from the base of the shoots. The analysis of these sections were realized using an image analyzing technology. The anatomical modifications induced by the stimulus concern all the elements of the wood structure. They generate repercussions on the physical properties of the wood of micro samples composed exclusively of gelatinous fibers. As the stimulus is applied during increasing duration it appears that the formation of the tissues in the opposite wood and in the tension wood requires a relatively short time of presentation. It shows also the rapidity of reaction of the shoots estimated by the latent period. Short duration events are capable to produce repercussions on the wood structure. The rate of cellular division, more important in the tension wood tissues, as measured on the upper face of a bent axis leads to a pith eccentricity in the shoot. The formation of tension wood, a modification of the secondary growth and the movement of the axis are the major modifications quantitatively linked to the intensity of the stimulus. Moreover, the evolution of the measured parameters demonstrates the existence of a natural equilibrium position of the shoots, different from the vertical position, and to which they attempt to return by an straightening or a sagging motion induced by the tension wood tissue. All these results indicated that tension wood should not be considered as a defect but rather as a efficient mechanism for the shoot allowing adaptation and harmonious development in its own environment. [less ▲]

Petite réflexion sur la qualité du bois d'épicéa

in Forêt Wallonne (2002), (60), 24-25

En termes de qualité du bois, l'influence du sylviculteur est déterminante. En effet, dès la décision de plantation, et ensuite, par le jeu des soins culturaux et des éclaircies, il va façonner, compte ... [more ▼]

En termes de qualité du bois, l'influence du sylviculteur est déterminante. En effet, dès la décision de plantation, et ensuite, par le jeu des soins culturaux et des éclaircies, il va façonner, compte tenu des conditions environnementales, les caractéristiques de la matière première qui en définiront les aptitudes technologiques. [less ▲]

Comparison of basic density and longitudinal shrinkage in tension wood and opposite wood in young stems of Poplar (P. euramericana cv “ Ghoy ”) when subjected to a gravitational stimulus

in Canadian Journal of Forest Research = Journal Canadien de la Recherche Forestière (2001), 31(10), 1676-1683

In a green house, under controlled conditions, young shoots, taken from poplar cuttings (P. euramericana cv “ Ghoy ”), were artificially inclined in order to quantify the modifications of physical ... [more ▼]

In a green house, under controlled conditions, young shoots, taken from poplar cuttings (P. euramericana cv “ Ghoy ”), were artificially inclined in order to quantify the modifications of physical properties induced by a gravitational stimulus. At the end of the growing season, basic density and longitudinal shrinkage were measured on very small samples taken from pure tension wood tissue observed on the upper face of the inclined axis and compared with opposite wood tissue, free of gelatinous fibers, developed on the opposite lower face. In a second step, shoots bend at two different lean intensities were analyzed. On young poplar wood, gravitational stimulus was found to have a significant effect on physical properties. Relations between basic density and longitudinal shrinkage are different depending on the types of wood considered. Shrinkage appears more sensitive to lean intensity in the range considered here [less ▲]

Du chêne au tonneau

in Courrier du Bois (2000), 129

La tonnellerie, activité à la fois artisanale et industrielle, tire profit des plus beaux chênes. Si le mode de fabrication traditionnel du tonneau n'a pratiquement pas changé depuis son invention par les ... [more ▼]

La tonnellerie, activité à la fois artisanale et industrielle, tire profit des plus beaux chênes. Si le mode de fabrication traditionnel du tonneau n'a pratiquement pas changé depuis son invention par les Celtes il y a plus de 2000 ans, certains développements technologiques sont venus aider les artisans dans leur travail quotidien. Parallèlement, le progrès des connaissances dans les sciences du bois, de la chimie et de la microbiologie nous ont appris à quel point l'élevage du vin en fûts de chêne reste une étape essentielle dans la maturation de ce liquide sacré. [less ▲]

La douce ivresse du chêne

in Forêt Wallonne (1999), 43

Il est une des applications du bois de chêne qui déchaîne les passions et en magnifie la matière. Nous voulons bien sûr faire référence à la tonnellerie, cet artisanat de qualité intimement lié à la ... [more ▼]

Il est une des applications du bois de chêne qui déchaîne les passions et en magnifie la matière. Nous voulons bien sûr faire référence à la tonnellerie, cet artisanat de qualité intimement lié à la culture européenne depuis plusieurs siècles et symbole de la communion entre la vigne et l'arbre. [less ▲]

Le Mélèze

in Courrier du Bois (1999), 125

De la famille des pinacées, le Mélèze, ou plutôt les Mélèzes, car ils sont trois chez nous à se partager ce titre générique, produisent un bois à la durabilité reconnue et à l'esthétique appréciée. Leurs ... [more ▼]

De la famille des pinacées, le Mélèze, ou plutôt les Mélèzes, car ils sont trois chez nous à se partager ce titre générique, produisent un bois à la durabilité reconnue et à l'esthétique appréciée. Leurs qualités technologiques sont susceptibles de satisfaire les exigences des utilisateurs dans des domaines très variés, tant en usage intérieur qu'extérieur. Cette essence n'a cependant pas la popularité qu'elle mérite auprès des sylviculteurs, malgré un potentiel de croissance élevé. [less ▲]

Le bois de tension. 1 Définition et distribution dans l'arbre.

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (1997), 1(2), 100-112

Aperçu de la qualité du bois de Chêne rouge d'Amérique

in Bulletin des Recherches Agronomiques de Gembloux (1992), 27(3), 309-325