Next Article in Journal
Phenology and Synchrony of Scymnus coniferarum (Coleoptera: Coccinellidae) with Multiple Adelgid Species in the Puget Sound, WA, USA
Next Article in Special Issue
Effect of Rotation Age and Thinning Regime on Visual and Structural Lumber Grades of Douglas-Fir Logs
Previous Article in Journal
Changes in Phylogenetic Community Structure of the Seedling Layer Following Hurricane Disturbance in a Human-Impacted Tropical Forest
Previous Article in Special Issue
Preferences for Urban Building Materials: Does Building Culture Background Matter?
Article Menu
Issue 9 (September) cover image

Export Article

Open AccessArticle
Forests 2018, 9(9), 557;

Surface Changes of Selected Hardwoods Due to Weather Conditions

Faculty of Wood Sciences and Technology, Technical University in Zvolen, T.G. Masaryka 24, 960 53 Zvolen, Slovakia
Faculty of Forestry and Wood Sciences, Czech University of Life Sciences in Prague, Kamýcká 129, 16521 Praha 6-Suchdol, Czech Republic
Author to whom correspondence should be addressed.
Received: 14 August 2018 / Revised: 6 September 2018 / Accepted: 7 September 2018 / Published: 11 September 2018
(This article belongs to the Special Issue Wood Properties and Processing)
Full-Text   |   PDF [18082 KB, uploaded 19 September 2018]   |  


The study is focused on the surface changes of five hardwoods (oak, black locust, poplar, alder and maple) that were exposed to natural weathering for 24 months in the climatic conditions of Central Europe. Colour, roughness, visual and chemical changes of exposed surface structures were examined. The lowest total colour changes (ΔE*) were found for oak (23.77), the highest being recorded for maple (34.19). Roughness differences after 24-month exposure (ΔRa) showed minimal changes in poplar wood (9.41); the highest changes in roughness were found on the surface of alder (22.18). The presence of mould and blue stains was found on the surface of maple, alder and poplar. Chemical changes were characterized by lignin and hemicelluloses degradation. Decreases of both methoxy and carbonyl groups, cleavage of bonds in lignin and hemicelluloses, oxidation reaction and formation of new chromophores were observed. In the initial phases of the degradation process, the discoloration was related to chemical changes; in the longer period, the greying due to settling of dust particles and action of mould influenced the wood colour. The data were confirmed by confocal laser scanning microscopy. The obtained results revealed degradation processes of tested hardwood surfaces exposed to external environmental factors. View Full-Text
Keywords: chemical changes; colour changes; infrared spectroscopy; hardwoods; roughness chemical changes; colour changes; infrared spectroscopy; hardwoods; roughness

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).

Share & Cite This Article

MDPI and ACS Style

Kubovský, I.; Oberhofnerová, E.; Kačík, F.; Pánek, M. Surface Changes of Selected Hardwoods Due to Weather Conditions. Forests 2018, 9, 557.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics



[Return to top]
Forests EISSN 1999-4907 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top