Abstract
The zeen oak (Quercus faginea Lamk.) is a deciduous oak whose presence can range from meso-Mediterranean to the supra-Mediterranean level. It is considered an endemic taxon of the western Mediterranean forest. It would be represented in the Tlemcen Mountains and in particular in the Moutas reserve by a subspecies: Quercus faginea subsp. tlemcenensis (DC.) M. Among the ecological factors that contributes to its weakening and threaten it over the last twenty years. The water deficits recorded in the reserve and mainly due to the shift of ombrotypes from hyper-subhumid to upper semi-arid. However, the taxon shows a better ability to resist these deficits and precipitation breaks by initiating its resilience at the level of depressions benefiting from water compensation.