In Uruguay, Gleditsia triacanthos (known as honey locust) is an exotic tree species categorized as invasive; it produces severe ecological impact as it displaces native species, causing changes in the structure of the native forest community. Being extremely difficult to control, it is widely distributed through Uruguay and neighbouring countries. However, one way to mitigate its negative impact is to identify opportunities to use it by revaluating its biological products. This work aims to study the applicability of this species as a source of both wood and non-wood products, transforming it from a problem to a resource. In order to do this, its natural durability was determined, and the extractives of the heartwood (particularly the tannin) were studied. Tannins have a great structural diversity and biochemical characteristics, such as their biocidal activity, making them suitable for wood protection. The extraction of the wood was done by ethanol infusion for 24 hours; once the yield of the extraction was determined, the tannins were quantified and analysed by FTIR. The obtained extract was then taken to a concentration of 5% (w/w), and combined with boric acid (2%) and hexamine (1%). Sapwood samples of Pinus taeda and Eucalyptus grandis were impregnated by vacuum – vacuum with the resulting mixture. The resistance of the treated wood was tested against two decay fungi, Coriolus versicolor and Gloeophyllum trabeum. The results show that Gleditsia triacanthos wood is moderately durable, allowing its use with the appropriate treatment in situations of greater risk of deterioration. The FTIR analysis verified the presence of polyphenols in the heartwood extract, and testing the treated samples proved the effectiveness of the mixture as a wood protector.

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