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The hips of wild roses (Rosa spp.) contain many healthful compounds such as vitamins and antioxidants. There is great interest in commercial cultivation but before this can occur, questions regarding plant reproduction and pollinators need to be addressed. Preliminary trials from 2004 investigated the pollination biology of five native or naturalized roses in Ontario and Prince Edward Island, Canada. The reproductive systems of Rosa blanda, R. canina, R. cinnamomea, R. multiflora and R. virginiana were investigated through pollination trials, and the potential pollinators of these species were surveyed. Hip and seed production by agamospermy, automatic autogamy, geitonogamy, xenogamy, emasculation control and open-pollination were tested for each species. Reproductive success, the number of hips set over the number of flowers, was calculated for each treatment. Rosa blanda and R. multiflora reproduced by open-pollination, geitonogamy and xenogamy; R. canina and R. virginiana were also autogamous. Both R. multiflora and R. virginiana set one hip asexually (through agamospermy). Interestingly, R. cinnamomea did not set fruit in any treatment or site. Pollinator activity was quantified twice in the season for each species. The number, type (most were hover flies(Syrphidae) or bees (Hymenoptera)), and behavior of insect visitors, as well as the time spent foraging, was recorded during 10 minute intervals on an hourly basis. Insect visitation rates were highest between 0900 and 1200, and foraging rates peaked sharply at 0900, indicating the probable period when the most pollen was available. Identified bee genera included Andrena, Apis, Augochlorella, Bombus, Calliposis, Ceratina, Halictus, Hylaeus, Lassioglossum, and Xylocopa.