Distance-dependent effects of the invasive Lupinus polyphyllus on native plants
Lupinus polyphyllus (Fabaceae) (EPPO observation list of invasive alien plants) is native to North America and a widespread alien species within the EPPO region. The authors of the present study set up field experiments in Sweden to evaluate the effects of L. polyphyllus on pollination and reproductive success of two native herbaceous plants, Lotus corniculatus and Lychnis viscaria. The experiments were conducted in 2011, and L. polyphyllus was transplanted along transects with potted individuals of each native plant placed at different distances from the invasive population in a replicated design. Pollinator visits were monitored at defined periods in the summer months for periods of ten minutes per census. Reproductive success was measured by collecting fruits. The authors observed that total pollinator visitation rates for L. corniculatus were negatively related to distance from the invasive population and for this species reproductive success was higher close to L. polyphyllus. For L. viscaria pollinator visitation and reproductive success was unaffected by distance.
Sources
Jackobsson A, Padron B, Ǻgren J (2015) Distance-dependent effects of invasive Lupinus polyphyllus on pollination and reproductive success of two native herbs. Basic and Applied Ecology 16, 120-127.