Wood is more and more important material. Since the availability of wood will presumably be scarce by year 2020, it will be more frequently reused and recycled. We tried to determine the effect of natural ageing on the selected properties of spruce and chestnut. The tested wood was a several decades old chestnut pole (Castanea sativa)and a 6 year old spruce beam (Picea abies). The resistance to the different wood decay fungi: Gloeophyllum trabeum, Antrodia vaillantii, Hypoxylon fragiforme, Pleurotus ostreatus, and Trametes versicolor was determined. Mechanical properties were measured by a 3-point bending test (modulus of elasticity) and compressive strength of samples. Changes in water uptake were defined with the use of tensiometre. Extractives in wood were determined by using 3 different solvents: water, 70 % methanol, and cyclohexane. The colour of the aged wood was numerically evaluated by the CIE L*, a*, b* system. The test results show that the relevant properties of chestnut did not change significantly. In comparison to the spruce, even after several decades of use, wood kept the resistance against the wood decay fungi. Preserved mechanical properties and low capillary water uptakewere also observed with chestnut. The most effective solvent for extraction is water, the same with chestnut and spruce. On the other site the 6 year old spruce has turned out to be a less susceptible wood species, with higher weight loss, higher water capillary uptake, and lower amount of extractives. Over the years, the both wood species changed natural colour which turned darker with age.
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