EN
The field experiments were carried out at Chrząstowo near Nakło nad Notecią in three consecutive vegetation seasons (2005–2007). The occurrence of insects with the hemipteroidal mouthpart on red fescue (Festuca rubra L.) cv. Mirena grown for seed, depending on developmental phases generative (start of heading, full heading, full flowering and milk-dough maturity) and vegetative (middle of August, beginning of September, middle of September) was investigated. The results of performed studies showed that Hemiptera occurred at a higher frequency, as compared with Thysanoptera. A large number of insects were caught especially during the vegetative development phase. In both years of full red fescue use the number of Thysanoptera decreased, and Hemiptera increased from the start of heading to milk-dough maturity of red festuce.