The fungus Sphaeropsis sapinea (Fnr.) Dyko & Sutton Syn: Diplodia pinea (Desim.) Kicx. was shorvn to be the agent causing bro\vn discoloration, resin fIo\v and dwarfing on the current-year shoots and needles on 2-4 year old Pinus pinaster and Pinus pinea trees in the summer of 1991. The trees werc in plantation areas \vithin Belgrad Forest ncar Kemerburgaz, 25 km NYV of İstanbul, Turkey. Field observations and laboratory examinations revealed that the disease was also present in several other pine plantations, ineluding those up to 25 ycars old, probably contributing to the stem deformations and degredation observed throughout the İstanbul region.