Historic Fire and Canopy Disturbance Dynamics in an Oak-Pine (Quercus-Pinus) Forest of the Missouri Ozarks (1624–2010)


Chad B. King

Additional Authors:

Rose-Marie Muzika


June 2014


Dendrochronology, disturbance, Missouri Ozarks, Pinus echinata, Quercus alba

ABSTRACT Studies of historic forest disturbances provide an important context for the ecological dynamics that affect forest structure and successional trajectory. Previous historical disturbance research in the Missouri Ozark Highlands has highlighted the dynamics of fire regimes. However, little is known concerning canopy disturbance regimes in this region. The primary objective of this study was to reconstruct the history of multiple disturbances at a site that was known for having both historic Native and Euro-American activity. We analyzed the radial growth of shortleaf pine (Pinus echinata Mill.) and white oak (Quercus alba L.) to infer growth release events and documented historic fire events based on fire-scarred P. echinata. The majority of trees (87%) exhibited at least one growth release between 1624 and 2000 with the earliest growth release occurring in 1645. A total of 39 fires were documented between 1706 and 1915. Mean duration of growth releases for both species was approximately six years. We documented five stand-wide canopy disturbance events between 1740 and 2000. However, most growth release events were asynchronous, suggesting that gap dynamics was an important process in this forest. Trees exhibiting multiple releases that on average lasted six years suggest that trees required multiple gap openings to attain canopy status. We speculate that even with a high historic fire frequency (MFI¼5.5 years), gap dynamics was the primary process for P. echinata and Q. alba to attain canopy status in this forest.