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Abstract PremiseReproductive fitness in plants is often determined by the quantity and quality of pollen transferred by pollinators. However, many fitness studies measure only female fitness or rely on proxies for male fitness. Here we assessed how five bee taxon groups affect male fitness in a prairie plant by quantifying pollen removal, visitation, and siring success using paternity assignments and a unique pollinator visitation experiment. MethodsInEchinacea angustifolia, we measured per‐visit pollen removal for each pollinator taxon and estimated the number of pollen grains needed for successful ovule fertilization. Additionally, we directly measured pollinator influence on siring by allowing only one bee taxon to visit each pollen‐donor plant, while open‐pollinated plants acted as unrestricted pollen recipients. We genotyped the resulting offspring, assigned paternity, and used aster statistical models to quantify siring success. ResultsSiring success of pollen‐donor plants differed among the five pollinator groups. Nongrooming male bees were associated with increased siring success. Bees from all taxa removed most of the flowering head's pollen in one visit. However, coneflower‐specialist beeAndrena helianthiformisremoved the most pollen per visit. Female fitness and proxy measures of male fitness, such as pollinator visitation and pollen removal, did not align with our direct quantifications of male fitness. ConclusionsOur results illustrate the need for more studies to directly quantify male fitness, and we caution against using male fitness proxy measures. In addition, conservation efforts that preserve a diverse pollinator community can benefit plants in fragmented landscapes. 

Summary A recent study posited that fire in grasslands promotes persistence of plant species by improving mating opportunities and reproductive outcomes. We devised an investigation to test these predicted mechanisms in two widespread, long‐lived perennials. We expect fire to synchronize flowering, increase mating and boost seed set.We quantified individual flowering phenology and seed set ofLiatris asperaandSolidago speciosafor 3 yr on a preserve in Minnesota, USA. The preserve comprises two management units burned on alternating years, allowing for comparisons between plants in burned and unburned areas within the same year, and plants in the same area across years with and without burns.Fire increased flowering synchrony and increased time between start date and peak flowering. Individuals of both species that initiated flowering later in the season had higher seed set. Fire was associated with substantially higher flowering rates and seed set inL.asperabut notS.speciosa. InL.aspera, greater synchrony was associated with increased mean seed set.Although fire affected flowering phenology in both species, reproductive success improved only in the species in which fire also synchronized among‐year flowering. Our results support the hypothesis that reproduction in some grassland species benefits from fire.