December 6, 2016 at 1:00 PM central time; by Dr. Benjamin Knapp, University of Missouri
Abstract: Land managers are using frequent prescribed burning to create or maintain open-structure ecosystems. A study established in 1949 in oak-hickory forests of southeastern Missouri demonstrates effects of one- and four-year fire return intervals on forest development through time relative to an unburned control. Repeated burning increased the rate of mortality for small-diameter woody stems, but the mortality of small stems over the long-term was also high in the unburned control due to stand development processes. In contrast to the unburned control, however, repeated burning prohibited the recruitment of new trees to the overstory. After > 60 years of repeated prescribed burning, differences in forest structure and composition among the treatments could be attributed to both 1) effects of fire on survival of the original population of trees, and 2) effects of fire on the persistence and development of new individuals. These processes and other considerations for long-term burning in oak-hickory forests will be discussed.