Sponsor: Tallgrass Praire & Oak Savanna Fire Science Consortium
Presenter: Dan Dey, research forester, US Forest Service Northern Research Station
Sustaining oak forests and restoring oak savannas and woodlands are increasingly common management goals in the Midwest and Great Lakes Regions. Sustaining oak forests requires successful regeneration and recruitment into the overstory. The regeneration potential of oak following a disturbance or harvest that initiates stand regeneration is determined largely by the size structure of oak before the event. Collectively, regeneration from (1) seed, (2) advance reproduction, and (3) stump sprouts contribute to oak regeneration but vary in their competitive capacity. Oak regeneration potential is modified by site, competitor regeneration potential and management input.
Prescribed fire is increasingly being used to promote oak regeneration with mixed results, and it is required to restore oak savannas and woodlands. Oak has many silvical traits that make it well adapted to fire. Fire can promote oak regeneration, but it also can reduce it, promote competing vegetation including invasive species, and retard oak recruitment into the overstory. Fire is a tool that can be used to sustain oak forests if it is applied judiciously with knowledge of oak forest ecology and stand dynamics, and with basic forest inventory information. Combining prescribed fire with thinning or harvesting can be effective in increasing oak regeneration potential and dominance in future stands, and it is a good approach to accelerating the restoration of oak savannas and woodlands.