translate English to French: The four species studied, Pacific silver fir (Abiesamabilis Dougl. ex Forbs), western hemlock (Tsugaheterophylla (Raf.)
Les quatre essences étudiées, le Sapin gracieux (Abiesamabilis Dougl. ex Forbs), la Pruche de l'Ouest (Tsugaheterophylla (Raf.)