EN
In 2009–2010, the major species pollinating winter oilseed rape Brassica napus L. growing in the microregion of Olsztyn was the honeybee Apis mellifera L., occurring in small numbers. Likewise, not numerous bumblebee Bombus Latr. and solitary bees of the family Andrenidae, played a complementary role. The set of pollinators reaching 3986–7798 indiv./ha of „bee convertion factor” should be considered as highly insufficient for good pollination of winter oilseed rape plantations.