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Whereas the Coastal Plain of the southeastern United States historically experienced fire primarily during the mid‐summer lightning season, managers today typically apply prescribed fire during the late winter or early spring months. The ecological implications of this discrepancy remain poorly understood, especially with regard to pollinators and their interactions with flowers. In a replicated field experiment, we compared the abundance and richness of bees and bee–flower interactions among pine savanna plots in Florida that were burned either during the winter, spring, summer, or fall. We netted 92 bee species from 77 species of flowers, representing 435 unique bee–flower interactions in total. When analyzing the results from each month separately, we detected significant short‐term reductions in the number of bees and bee–flower interactions following fires regardless of season. Although bee abundance and richness did not differ over the entire season, bee–flower interaction richness was significantly higher overall in spring and summer plots than in fall plots and the composition of both bees and bee–flower interactions differed significantly among treatments. Several bee–flower interactions were significantly associated with one or more of the treatments. Some of these associations could be attributed to differences in flowering phenology among treatments. Taken together, our findings suggest that season of fire has modest but potentially important implications for interactions between bees and flowers in southeastern pine ecosystems. Because most flowering plants within our study region are pollinated by a variety of bees and other insects, and most bees endemic to the region are polylectic, season of fire may not be very important to either group overall. However, the timing of fire may be more important to particular species including certain flower specialists and fire‐sensitive taxa such as butterflies. Future research targeting such species would be of interest. [ABSTRACT FROM AUTHOR]

Fire is a key determinant of vegetation structure and composition in ecosystems worldwide and is therefore an important management tool. The "pyrodiversity hypothesis", which postulates that biodiversity will increase as fire diversity increases, remains largely untested for pollinators, a group of high conservation concern. We tested the relationship between pollinator diversity and pyrodiversity based on a decade of burn history in Florida, as well as testing other parameters, including burn frequency, the percentage of area burned during the year of sampling, canopy openness, and various plant metrics. Both bees and butterflies responded positively to pyrodiversity and to the percentage of area burned during the year of sampling. In addition, our results indicate that pollinators, especially butterflies, may be sensitive to high burn frequency. Our findings reveal the important role fire history plays in shaping pollinator communities and demonstrate that increasing burn heterogeneity can benefit this fauna in fire‐managed landscapes. [ABSTRACT FROM AUTHOR]

Although most efforts to improve habitat for bees and other pollinators focus on floral resources, it is also important to consider the availability and suitability of nesting habitats in relation to various management activities.We used soil emergence traps to compare the number of ground‐nesting bees among treatments in a long‐term fire frequency study in Florida. We regularly moved the traps, a strategy that appears to greatly improve the efficacy of this sampling approach. The experiment consisted of forested plots that have been burned annually, biennially or triennially for the past six decades as well as unburned reference plots.Bee abundance was significantly lower in the unburned plots than in any of the burn treatments and was higher in annual plots than triennial plots. Bee richness was significantly higher in plots burned annually than in unburned plots. Bee Shannon's diversity was significantly higher in plots burned biennially or triennially than in unuburned plots. Evenness was significantly lower in annually burned plots than in any of the other treatments.Indicator species analysis found six bee species to be significantly associated with one or more burn treatments. Four of them were strongly associated with plots burned annually or biennially while two species were significantly associated with plots burned biennially or triennially. None was significantly associated with unburned plots.Our findings suggest that frequent fires generally improve habitat for ground‐nesting bees in southeastern U.S. forests and that tolerances for particular burn frequencies vary by species. [ABSTRACT FROM AUTHOR]

Longleaf pine (Pinus palustris) ecosystems have been reduced dramatically throughout their range. Prescribed burning is considered the best way to restore and maintain plant communities associated with longleaf pine, but little is known about its effects on coarse woody debris and associated organisms. We conducted a 5-year study on the Osceola National Forest in northeastern Florida to determine how dormant-season prescribed burns at different frequencies (annual, biennial, quadrennial or unburned) applied over a 40-year period affected coarse woody debris volume, decomposition and nitrogen content, and subterranean termite (Reticulitermes spp.) activity. Burn frequency had no effect on standing dead tree or log volumes. However, freshly cut longleaf pine logs placed in the plots for four years lost significantly less mass in annually burned plots than in unburned plots. The annual exponential decay coefficient estimate from all logs was 0.14 yr-1 (SE = 0.01), with the estimated times for 50 and 95% loss being 5 and 21.4 years, respectively. Termite presence was unaffected by frequent burning, suggesting they were able to survive the fires underground or within wood, and that winter burning did not deplete their food resources. [ABSTRACT FROM AUTHOR]

Much of the once-dominant longleaf pine (Pinus palustris Mill.) ecosystem has been lost from the Coastal Plain of the southeastern United States and only a few scattered remnants of primary forest remain. Despite much interest in understanding and restoring this ecosystem, relatively few studies have attempted to characterize or assess the conservation status of the longleaf bee fauna. The objective of this study was to compare the diversity and composition of bee communities between primary and mature secondary (>100 years old) fire-maintained forests in Georgia and Florida. We used colored pan traps to sample bees at three primary and four secondary locations divided between two regions characterized by sandy (Eglin Air Force Base) or clayey (Red Hills) soils. There were no overall differences between primary and secondary forests in bee richness, diversity, evenness or abundance. Community composition differed among locations but we found no evidence that primary remnants provide critical habitat to sensitive bee species.