The subject of this thesis is a review of all European sawfly species, including the species that do not have regular outbreaks. The practical part of the thesis was carried out in an 80 years old spruce (Picea abies) stand in Prevalje, between years 2010 and 2012. All the prepupae forms on all six plots on the site near the town Prevalje were collected. Based on this data, the size of the population was determined. An attempt was made to raise adult insects in a controlled laboratoy environment from the prepupae. The majority of the sawfly subjects (71 %) were of the arvensis species and in the year 2012 C. arvensis was the culprit for defoliation. Besides the species bionomy climate conditions at the location, based on the air and soil temperature and precipitation were monitored. The results showed that air and soil temperature significantly impact the development of the C. arvensis and that the threshold temperature is 12 °C. We assume that the large amount of precipitation in the years 2008 and 2009 did not reduce the size of the population C. arvensis.