Many native and exotic forbs in Cascadia prairies share pollinators. That means that the timing of their flowering can be key to whether they compete for pollinator services. We manipulated the flowering phenology of two wxotic plants and examined the effects on the pollinator assemblages visiting seven native forbs, and the resulting seedset. We found surprisingly strong effects--both positive and negative--on native seed production, just by changing the timing of neighboring exotic flowers.
Plant-pollinator interactions, climate, and phenology