Forest pests and diseases are causing substantial losses in plantation and natural forests ( FAO, 2010). Also, area under tree cover is declining at regional level due to the factors such as drought, new pathogens and pests. Interactions between these factors, can have negative impact on biodiversity (Fischer et al. 2010; Parks and Bernier 2010;Carnicer et al. 2011).
Control of forest pests and diseases have received serious consideration ever since the problems have been identified. Integrated pest management including silvicultural and biological control methods are widely used for forest pest management. Mixing of tree species has been reported as a solution to reduce pest incidence and spread (McGradySteed et al., 1997; GoN, 2009) compared to monocultures. However, management of forest pests and diseases has received very low consideration in Nepal till date. This preliminary study, therefore, is an attempt to assess pests and diseases problems in different forest types of Nepal.