Prescribed Fire in Shrub Bogs

Shrub bogs have not typically been the primary target of prescribed fire programs and were even routinely “protected” from fires by the construction of firebreaks. This practice of protecting shrub bogs from fire stems from the misconception that forested wetlands should not burn and from practical concerns with fire control and smoke management. Recently, land stewards and ecologists have recognized that fire in shrub bogs is ecologically important and that past practices of fire suppression have had detrimental effects on plant species and on the maintenance of natural communities. Of particular importance is the ecotone of streamhead shrub bogs where concentrations of rare plants are known to occur and where firebreaks are often constructed.

In implementing a prescribed fire program with the goals of managing shrub bogs several considerations emerge:

1. It is important to let fires burn downslope from upland communities into shrub bogs in order to

• Discourage shrub encroachment into herbaceous plant communities thus maintaining rare plant habitat in ecotones.
• Maintain amphibian habitat.
• Burn holes in peat within basin shrub bogs to maintain diversity and habitat for rare plants.
• Mimic natural processes and maintain early successional plant communities.

2. Land stewards should monitor fire behavior in shrub bogs to ensure that goals are being met. Due to operational concerns, prescribed fires are often set under moderate environmental conditions when fires can be controlled. Under these conditions, fires may be less likely to sweep through wetlands such as shrub bogs. Thus, setting fires under more extreme conditions may be necessary for fires to sufficiently burn shrub bogs or for fires to burn holes in peat.

3. Using prescribed fires under conditions when shrub bogs will burn creates operational concerns such as:

• Fire control due to more extreme fire behavior in communities with high fuel loads.
• Igniting unplanned ground fires that produce excessive smoke when burning in shrub bogs with organic soils.

Depending on management goals, the frequency with which prescribed fire is applied to any community may vary. It has been recommended that streamhead shrub bogs be burned every 3-5 years and that the natural moisture gradient will limit fire spread downslope (Robertson et al. 1998). Basin shrub bogs can be managed to have vegetation structure similar to high or low pocosin. Longer fire return intervals would be employed to manage for a structure similar to high pocosin (5-8 year intervals) and shorter intervals for low pocosin (Robertson et al. 1998). The presence or absence of rare plants or animals may influence desired fire frequencies or season (Robertson et al. 1998). Life history information on the particular taxa should be referenced where available when planning a burn program.