Insect Flower Visitation Frequency and Seed Production in Relation to Patch Size of Viscaria vulgaris (Caryophyllaceae)

We examined frequency of pollinator visits, seed set, and seed predation in relation to plant patch size of the perennial caryophyllaceous herb Viscaria vulgaris in two areas in southern Sweden. The Dalsland area had approximately ten times more Viscaria plants per unit area than the Sma˙land area. Long-tongued bumblebees and to a lesser extent Lepidoptera were the most important pollinators in both areas. Honeybees and bumblebees with short proboscides were mainly nectar robbers and/or pollen collectors. Insect visitation per Viscaria plant and patch size were either unrelated or negatively correlated. However, bumblebee visitation was twice as high in the Dalsland area compared to Sma˙land, while no such difference was found in Lepidoptera