To restore tallgrass prairies, prescribed burns are used to replicate the historic fires that played a key role in maintaining the expanses of herbaceous vegetation. Although much is known about the effects of spring-applied burns on grasslands, burns during other seasons are increasingly recommended as an alternative management practice. Unfortunately, the effects of these alternative burns on plant-pollinator interactions are poorly understood. We address this gap in knowledge by examining the response of the plant community and its ability to recruit effective pollinators following three seasonal burn treatments (spring, summer, and fall). We focused on three specific research aims: First, we determined the response of the native flowering community after burning. Second, we established whether native perennial plants differ in their investment in recruiting pollinators. Third, we measured whether seasonal burns impact plant reproductive success. We studied plants from the milkweed family (Asclepias spp.) in addressing these three responses through plant surveys, sucrose concentration of collected nectar, plant biomass, and seed viability assays.
Results/Conclusions
Plant diversity increased significantly in summer burns and was almost as diverse in fall burns. The spring burn treatment had the lowest diversity. There was no significant difference between burn treatment in terms of nectar sucrose concentration, seed mass, or seed viability. Therefore, burn treatments seem to influence flowering plant diversity as expected but does not greatly impact a plant’s investment in pollinator recruitment or reproductive success.