SUMMARY
Forest pest detection and prognosis are important works in forest protection activities, and because of these it can be known the health of forests at any time of year. In the sylviculture point of view, there are the primary meaning forestry pests and pests distinguish secondary, the first that stands against a culture and under certain conditions of vegetation, climate and mass medium can replicate. Establishing forecasts to reflect the real situation of forest sampling of surfaces requires control data referring to quantity, quality and rate of injuries. Thus, for each stand or for groups of stands with similar conditions (in terms of stationary and stand composition and age) and the same degree of defoliation, it will be taken 32 samples of litter and soil. Each sample will represent the collected material on a surface of 25 x 25 cm. The data presented in this paper, on the forecast Tortrix viridana, 2010 shows that infestations will be very weak and weak, except for two bodies Forest Forest Departments in Oradea and Satu Mare, where defoliation will be strong and very strong.