Using the RESISTOGRAPH ® to distinguish different types of wood rot on living silver fir in Molise (Italy). The study was performed in two silver-fir forests (Abies alba Mill.) located in Alto Molise, Province of Isernia: Collemeluccio, near Pescolanciano and Abeti Soprani near Capracotta. The aim of this work was to distin guish different types of wood rot on living silver fir individuals by using the RESISTOGRAPH ® (IML-RESI E400), a device that allows to estimate the variation of wood density by measuring the resistance to micro-perfora tion. The occurrence of different types of wood rot (white rot and brown rot) in living trees was pointed out and discriminated by the device. In the detected deteriorated zones, fungal pathogens and decomposers were isolated and identified, causing either white (Phellinus hartigii, Ganoderma adspersum, Heterobasidion abi etinum and Armillaria ostoyae) or brown rot (Fomitopsis pinicola).