Alien tree species are most often found in our country as park trees, and are mostly independent with several human cultivation interventions. The wood of these trees varies in structure, and discolourations is widespread due to frequent damage. Drying is an important process before further processing of wood, so we studied the drying characteristics of Box elder, Horse chestnut and Black locust. Three thicknesses (22 mm, 28 mm and 46 mm) of each species were dried at three temperatures (20 °C, 40 °C and 60 °C) and the drying process was monitored by the oven drying method. From the individual sections of the drying curves, the drying rate above and below the FSP, the half adjusting times and the diffusion coefficients were determined. We also performed the final quality control (average moisture content, moisture content gradient, case hardening and visual assessment). Drying rates were highly variable between species in the first phase, and more significant drying below the FSP confirmed expectations, as the diffusion coefficients increased with increasing temperature and were in most cases lower in denser Black locust than in Box elder and Horse chestnut. Similar regularities were also found with half adjusting times, where we also confirmed the longer drying times of thicker specimens. The quality of the dried wood was good, but we must point out the great danger of collapse in the Box elder.
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