The effects of acidic precipitation on the main tree species of Kaz Mountains in Biga Peninsula were investigated. Acidic precipitation were first observed with small yellow spots of acid burns on the needles. Then the total chlorophyll content of the Pinus nigra subsp.pallasiana and Abies equi-trojani Aschers sint needles with different age were detected. We have determined a difference in the total chlorophyll content of the needles depending on the species, needle age, altitude, direction and the amount of pollution
