The research into the occurrence of herbivorous heteroptera of Orthops genus on Sosnowski’s hogweed (Heracleum sosnowskyi Manden.) was carried out over 1999–2002 in the vicinity of Bydgoszcz. The analysis of the faunistic material collected of Heteroptera order showed the occurrence of 3 species where dominant heteroptera were represented by: Orthops campestris L. (48.57%) and Orthops kalmi L.(44.91%), while Orthops basalis Costa was scarce. The maximum abundance of these species coincided with full flowering and the beginning of hogweed fruit formation.

Water extractsfrom selected Geraniaceae plants, to which paraffin oil was added as adjuvant, were tested. It was observed that the plant extracts researched limited Colorado potato beetle feeding and development and adding adjuvant increased the effects. The highest antifeedant activity towards Colorado potato beetlesand their larvae wasobs erved in extractsobtained from Pelargonium × hortorum Bailey and Geranium pusillum L. The extract from Pelargonium × hortorum Bailey added to food showed a negative effect on the development of female reproductive organs and embryo development and showed the highest effectiveness in field conditions.