Wood Density and Ring Width in Quercus rotundifolia Trees in Southern Portugal

Abstract

Quercus rotundifolia Lam., known as holm oak or evergreen oak, occurs naturally in the western Mediterranean region, mainly as part of the agroforestry or agrosilvopastoral systems in Portugal (“montado”) and Spain (“dehesa”), and is economically important for acorn production. Less attention has been given to Q. rotundifolia wood, and its density variability is not known, namely related to tree growth. The wood density of 20 Q. rotundifolia trees was measured along the radial direction by X-ray densitometry and the factors responsible for ring width and wood density variation within and between trees were investigated at two sites located within the main species region in southern Portugal. Ring width was significantly different between sites, with an average of 1.81 mm and 1.55 mm. Wood density was very high and averaged between 888 kg/m3 and 914 kg/m3 but not significantly different between sites. Ring width and wood density showed a positive and significant correlation at both sites. Cambial age was the main source of variation for ring width and wood density, while between-tree effects accounted for a considerable proportion of wood density variation. The results are an important contribution for the species valorisation aiming at high-value wood products, also adding knowledge on the species growth of interest for tree selection and sustainable management.

Compressive and Bending Strength Variations in the Properties of Portuguese Clear Oak Wood

“…Site S1 showed a fine soil texture, whereas site 2 and site 3 showed coarse and medium soil textures. The effects of soil on other oak species was already stated as regards their growth [29] and wood density [30]. In this case, a finer soil texture led to more hydric stress, which is reflected in the first layers of wood produced, which showed higher density (high proportion of latewood in the growth ring).…”

Above and belowground carbon stock of pine plantations and native oak forests coexisting in central Spain

“…Indeed, P. halepensis grow faster than both Quercus species (Cañellas et al 2008;Montero et al 2002). However, when this value was relativized to a common basal area, C stock in AG trees was higher in Quercus forests, probably due to the higher wood density of Quercus trees (888-914 kg/m 3 ) compared to Pinus halepensis (500-630 kg/m 3 ) (Hevia et al 2020; Sousa et al 2021). For most of the remaining fractions, C stock tended to be larger in Quercus forests (both gross and per-basal area values) mostly for roots and AG shrubs.…”

An Integrated Similarity Analysis of Anatomical and Physical Wood Properties of Tropical Species from India, Mozambique, and East Timor

“…Despite the wood density (FIS1) importance, the wood shrinkage and wood color, contributions were highlighted for the species distribution based on physical properties. In fact, wood density is greatly controlled by genetic factors [19], allowing the study of the effects of geographical provenance on wood density for a higher number of species from temperate to tropical regions due to their practical implications for tree improvement programs (e.g., [22][23][24][25]60]). In neotropical species, for example, wood density was found to be highly phylogenetically conserved [20].…”

“…Wood density is of high interest for taxonomic and phylogenetic studies since it is greatly controlled by genetic factors [19,20]. Thus, the genetic and/or geographical provenance effects on wood density are often studied for the most valued woods due to their practical implications for tree breeding and conservation programs (e.g., [21][22][23][24][25]).…”