Kraft pulp produced from juvenile and mature wood from thirty-two-yearold Corymbia citriodora trees was evaluated. The stem was subdivided into regions of juvenile and mature wood, and then it was transformed into chips. These materials were then cooked in the Laboratory of Pulp and Paper at São Paulo State University (UNESP, Botucatu, SP, Brazil) and the physico-mechanical properties of the pu...

the mean fiber length of three beech trees (fagus orientalis l.) at the lower and higher points (1% and 75% tree height) of the stem at an intermediate altitude (500-1000m) in the caspian forests in sari region were 1.36 and 1.22mm respectively, close to the values in three trees at high altitude (1000-1500m), that were found to be 1.39 and 1.36 mm. the mean fiber lengths of the whole stem, usi...

To satisfy the increasing demand for forest products, much of the future timber supply will be from improved trees grown on managed plantations. This fast-grown resource will tend to be harvested in short age rotations and will contain higher proportions of juvenile wood than that of current harvests. In anticipation of this resource, definitive information is needed on the influence of juvenil...

Intensive forest management, with a heavy emphasis on ecosystem management and restoring or maintaining forest health, will result in the removal of smaller diameter materials from the forest. This increases the probability of higher juvenile wood content in the harvested materials. The purpose of this study was to compare the performance of loblolly pine juvenile and mature wood unbleached the...

The length of juvenility or number of years a tree produces juvenile wood at a fixed height can be defined by the age of the wood at which properties change from juvenile to mature wood. This paper estimates the age of transition from juvenile to mature wood based on ring specific gravity (SG), proportion of annual ring in latewood, and ring average microfibril angle (MFA). The threshold method...

In this work the effect of age and location within the stem on pH and buffering capacity of radiata pine sapwood was investigated. Mature and juvenile wood samples from three different heights in the trunk were obtained from 20, 25, and 30 year-old trees. Aqueous wood extracts from the samples were used to determine the pH and buffering capacity of wood. Results show a significant effect of age...

Longitudinal compression can help wood form some folds on the wood cell walls after a suitable softening procedure. These folds can enhance the oneand multi-dimensional bending performances of wood. The longitudinal compression properties of alkali-treated juvenile and mature northeast Chinese ash (Fraxinus mandshurica Rupr.) were analyzed. Elastic and elastic-plastic stages were inferred from ...

Many traits are known to be important in determining the value of Eucalyptus wood as sawn timber. The commercial importance of the microfi bril angle (MFA) for wood quality is well established for a range of softwoods, but is less clear for hardwood species. For instance, the relationships of MFA with wood stiffness and compressive strength are unknown in Eucalyptus. Therefore, the aim of this ...

The impact of weed control and fertili7Mion on incnajed tree growth is positive and significant but the effects on wood pmper6es are not well known. lncrernent axes mn, coUac@d from lobldly pine (pinus faeda L) trees growing on an existing site-preparation experiment in the lower Piedmont of Georgia at age 15. The levels of site praparation were: ldearcut only; P-chainsaw, 3-shear and chop; 4-s...

DLOUhá, J., ALMÉRAS, T., CLAIR, B., GRIL, J., hORáčEK, p.: Biomechani-cal performances of trees in the phase of active reorientation. Acta univ. agric. et silvic. Mendel. Brun., 2008, LVI, No. 5, pp. 00–00 The purpose of the present paper was to investigate the accumulation of growth stresses in a cross section of a tree in active reorientation process and its biomechanical performances i.e. up...