| extensive tree health monitoring networks are useful in revealing the impacts of widespread biotic damage in boreal forests. | we surveyed the regional distribution of conifer defoliation in finland with an extensive monitoring network during 1995-2006 (eu forest focus level i). the average defoliation in the whole finland was 10.3% in pine and 19.9% in spruce. the sharp changes were often related to abiotic and biotic factors. the mean age of the stand explained more than one half of the between-plot variance in defoliation. in a variance component analysis, the main effect of years was negligible, while most of the ra ... | 2010 | 19629733 |