Modelling wood density in European oak (Quercuspetraea and Quercusrobur) and simulating the silvicultural influence

Abstract

Wood density in relation to cambial age and ring width was studied in 23 trees of European oak (Quercuspetraea (Matt) Liebl. and Quercusrobur L.) from northeast France, and based on these relationships, a model predicting intratree wood density through cambial age and ring width was developed. Wood density is closely correlated with both cambial age and ring width, but its relationships with cambial age and ring width, to some extent, vary from tree to tree. The variation, however, does not show an appreciable pattern with tree height. The model developed is able to predict satisfactorily the average wood density of growth rings in European oak, and to explain the main part of the variation in wood density of individual trees. Furthermore, the model appears also possible to predict the average density of a given small piece of wood from any part of the merchantable bole of the trees. A general model, however, accounts for a relatively low percentage of the variation because there is large intertree variability of wood density in the species. The simulation results reveal that the dynamic silviculture applied to European oak might result in the production of denser and more uniform (in the sense of the radial variation of wood density) wood, compared with classical silviculture.

Climate-tree-growth relationships ofQuercus petraeaMill. stand in the Forest of Bercé (“Futaie des Clos”, Sarthe, France)

“…Total ring, earlywood and latewood ring-widths averaged 0.97, 0.42 and 0.55 mm, respectively. As previously known [14,22,53,54], latewood proportion ranged from 80 to 50% of total ring width according to cambial age (between 10 and 320 years) (Fig. 3) and there was a strong positive correlation between the total tree-ring width and latewood width (r 2 = 97%).…”

“…The oak ring width is usually considered as a good indicator of wood quality because wood properties (density, shrinkage, machinability…) are closely correlated with ring widths [39][40][41]. Thus, wide rings (> 1.5-2 mm) correspond to denser wood which is less favourable to veneer production (the main use of oak wood) because denser wood in this species is associated with higher shrinkage and machinability [14,53,54]. Thus, from this point of view, this oak grove can be considered as a high quality stand for veneer production.…”

“…Early-and latewood transitions within the annual rings were defined according to qualitative aspects. Earlywood is of low density, because of a high proportion of large vessels, whereas latewood, which is made small vessels and fibres, is of high density [53,54]. To reduce bias in the tree-ring measurements, early-and latewood data were collected by only one person.…”

Influence of wood density in tree-ring-based annual productivity assessments and its errors in Norway spruce

“…The relative stability in annual WD values is not calling for a correction of the biomass increment in such situation. It is probable that variations in WD would affect the estimation of biomass increment in species for which a relationship with ring width was already observed such oaks (Zhang et al, 1993;Bergès et al, 2008) or larch (Karlman et al, 2005). The contribution to the error in the prediction of biomass production is however likely to be important.…”

Genetic variation of the pilodyn-girth relationship in Norway spruce (Picea abies L [Karst])

“…La variabilité génétique de la relation entre la profondeur de pénétration de l'aiguille du pilodyn (une méthode indirecte de mesure de la densité du bois) et la circonférence de la tige a été étudiée aux niveaux provenance, famille (demi-frères) et (Leban and Duchanois, 1990) to prediction Houillier, 1991, 1992; Owoundi, 1992). Variation between stands in model shape or in model parameters is known and sometimes taken into consideration (Nepveu, 1991;Zhang et al, 1993).…”