Accessible Unlicensed Requires Authentication Published by De Gruyter July 31, 2020

Investigation of the material resistance and moisture performance of pubescent oak (Quercus pubescens)

Miha Humar ORCID logo, Angela Balzano, Samo Grbec, Jožica Gričar, Davor Kržišnik, Boštjan Lesar and Viljem Vek
From the journal Holzforschung


Forests are under great pressure due to climate changes. It is forecast that the importance of Mediterranean type forests will significantly increase. Among various types of oak species, pubescent oak (Quercus pubescens) will likely gain ecological and economic importance in the region south of Alps. Although this wood species is well known, there are not much data available about chemical properties and durability. A comprehensive analysis of extractives and durability against wood decay fungi was therefore performed. The results of the chemical analysis revealed that heartwood contains up to 20% of the extractives, with considerable amounts of phenols, including a fairly high concentration of Gallic acid (GAc). Anatomical structure, with high frequency of tylosis, resulted in good water exclusion efficacy. The presence of biologically active extractives and superior water exclusion efficacy resulted in good durability, as shown by basidiomycetes tests. Based on the laboratory data, factors that determine the service life of wood were calculated. Data indicate superior performance in above-ground applications.

Corresponding author: Miha Humar, Department of Wood Science and Technology, Biotechnical Faculty, University of Ljubljana, Rozna dolina, Ljubljana1000, Slovenia, E-mail:

Funding source: Javna Agencija za Raziskovalno Dejavnost RS

Award Identifier / Grant number: IC LES PST 0481-09

Award Identifier / Grant number: J4-7203

Award Identifier / Grant number: J4-9297

Award Identifier / Grant number: L4-7547

Award Identifier / Grant number: P4-0015

Award Identifier / Grant number: P4-0107

Funding source: Sustainable and innovative construction of smart buildings (TIGR4smart)

Award Identifier / Grant number: C3330-16-529003

Funding source: Wood and wood products over a lifetime (WOOLF)

Award Identifier / Grant number: OP20.03520


The authors would like to acknowledge technical support from Blaž Vivod and Gregor Skoberne.

  1. Author contribution: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.

  2. Research funding: The authors acknowledge the support of the Slovenian Research Agency (ARRS) within the framework of research projects L4-7547, J4-7203 and J4-9297, research programs P4-0015 and P4-0107, and the infrastructural centre (IC LES PST 0481-09). Part of the presented research was also supported by the project: Sustainable and innovative construction of smart buildings (TIGR4smart) (C3330-16-529003) and Wood and wood products over a lifetime (WOOLF) (OP20.03520).

  3. Conflict of interest statement: The authors declare no conflicts of interest.


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Received: 2020-02-13
Accepted: 2020-04-07
Published Online: 2020-07-31
Published in Print: 2021-01-26

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