New tools for extracting cork from Quercus suber L.: increasing productivity and reducing damage

Jesus Beira Davila, Cristina Prades Lopez, Ramon Santiago Beltran


Aim of study: The aim of this study is to test new tools designed to debark cork oak trees: mechanized tools to perform cutting operations (IPLA-Morell, Stihl MC200 and COVELESS) and manual tools to separate and extract the cork (cork pincers, MIJURO).
Area of study: Southwestern Spain.
Material and methods: One of the longstanding problems affecting the sector is the shortage of skilled labor to perform debarking due to the difficulty of handling axes and the temporary nature of the work. To overcome these problems, four debarking systems using the new tools were designed according to the morphological properties of cork oak. The viability of the debarking systems were evaluated based on productivity (kg · person–1 · hour–1), production costs (€ · t1) and percentage of pieces smaller than 400 cm2 (%), and compared with the traditional system. Debarking quality and operator experience were also evaluated. A total of 204 trees were debarked.
Main results: The new systems obtain better results: productivity is higher, the percentage of pieces is slightly lower and production costs are reduced, except for one system. Debarking quality improves with the new tools as cork is extracted in a more precise and cleaner manner, thus permitting cork manufacturers to obtain higher yields from the cork planks.
Research highlights: Semi-skilled operators using the new tools obtain very similar results to skilled operators using axes. This would therefore resolve the problem of the lack of skilled labor, while improving the working conditions of operators. The results demonstrate that the new tools are viable for cork debarking and can bring potential benefits to the sector.

Key words: Q. suber L.; cork debarking; mechanization; productivity; cork stripping damage; axe; IPLA_Morell, Sthil MC 200, COVELESS.

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DOI: 10.5424/fs/2014231-03012