Pollen loads of honeybees, bumblebees and hoverflies were analysed and pollination efficiency estimated, while they were visiting the flowers of Prunus spinosa L. (Blackthorn); Crataegus monogyna Jacq. (Hawthorn); Rosa canina L. (Dog Rose) and Rubus fruticosus L. (Bramble). The relative efficiency of the different insect groups varied, depending on the plant species being visited. In every instance the high constancy of the visitors, their rapid foraging rates and the amounts of pollen they carr
y, would ensure that they are adequate pollen-transfer agents.