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To quantify the impact of forest management practices and tree growth rate on the potential uses of Douglas-fir wood, nine physico-mechanical properties were studied on more than 1250 standardized clear specimens. These were collected from trees cut in 11 even-aged stands (six trees per stand) located in Wallonia (southern Belgium). Stands were 40 to 69 years old, and mean tree girth was ca. 150 cm. Mean ring width of the 66 trees ranged from 3 to more than 7 mm. Statistical analysis showed significant but weak effects of ring width on the studied properties. Considered jointly, mean ring width and cambial age of the test specimens only explained 28% to 40% of the variability of their properties. Also, when ring width increases, these properties display higher decreases in juvenile wood than in mature wood. From a technological standpoint, maintaining mean ring width under 4 mm in juvenile wood and 6 mm in mature wood should accommodate all potential uses of Douglas-fir wood. However, considering that density appeared to be the main driver of wood properties, our results and the literature corroborate the importance of genetic selection as a complement to silvicultural measures to improve or guarantee the technological properties of Douglas-fir wood. Key words: Douglas-fir, mechanical properties, ring width, clear wood specimen, wood quality. Afin de quantifier l'impact des modalites de gestion sylvicole, et donc de la vitesse de croissance des arbres sur les potentialites d'usage du Douglas, neuf proprietes physico-mecaniques ont ete mesurees sur plus de 1250 eprouvettes standardisees. Celles-ci sont issues d'arbres preleves dans 11 peuplements equiennes (six arbres/peuplement) situes en Wallonie (sud de la Belgique). L'age des peuplements varie de 40 a 69 ans, tandis que la circonference moyenne des arbres avoisine 150 cm. La largeur moyenne des cernes des 66 arbres varie ainsi de 3 a plus de 7 mm. Les analyses statistiques ont montre des effets significatifs mais faibles de la largeur des cernes sur les proprietes etudiees. Consideres ensemble, la largeur des cernes et l'age cambial des eprouvettes n'expliquent que 28 a 40 % de la variabilite des proprietes etudiees. D'autre part, lorsque la largeur des cernes augmente, ces proprietes diminuent davantage dans le bois juvenile que dans le bois mature. D'un point de vue technologique, limiter la largeur moyenne des cernes a 4 et 6 mm, respectivement, dans le bois juvenile et mature, permet de maintenir les meilleures potentialites d'usages du bois. Cependant, etant donne que la densite apparait comme le principal determinant des proprietes mecaniques, nos resultats et la litterature corroborent l'importance de la selection genetique en complement de la gestion sylvicole en vue d'ameliorer ou de garantir les proprietes technologiques du bois de Douglas. Mots-cles: Douglas, proprietes mecaniques, largeur de cerne, eprouvettes sans defaut, qualite du bois., Introduction Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) was introduced into the Ardenne region of Belgium in 1871 and currently covers around 23 000 ha, i.e., slightly less than 10% of the [...]