Monooxygenase involved in the biosynthesis of labdane-related diterpenes natural products (PubMed:26976595). Catalyzes the oxidation of ferruginol to produce salviol (PubMed:26976595). Salviol is an intermediate in the biosynthesis of carnosate, a potent antioxidant (PubMed:26976595). ferruginol + O2 + reduced [NADPH--hemoprotein reductase] = H(+) + H2O + oxidized [NADPH--hemoprotein reductase] + salviol Secondary metabolite biosynthesis; terpenoid biosynthesis. Expressed in leaf glandular trichomes. Belongs to the cytochrome P450 family.