Abstract
Between 2011 and 2014, foresters and landowners in Missouri reported abnormally high levels of white oak (Quercus alba) mortality, with large numbers of white oak trees dying abruptly after leaf-out or during late summer. Entire tree crowns rapidly wilted and dead leaves remained attached to branches. Foresters reported that mortality occurred mostly on lower slopes and in the bottoms of upland drainages. This new syndrome was named rapid white oak mortality (RWOM). Reports of RWOM peaked in 2012, but reports of new mortality are still being received. A number of regional events, including a late spring freeze in 2007, record amounts of precipitation in 2008 and 2009, a jumping oak gall outbreak in 2010, and a severe drought in 2012 may have played a role in the mortality event. The Iowa Department of Natural Resources also received reports of white oak mortality between 2011 and 2014. A one-year study was conducted during 2014 to describe the geographic distribution and the characteristics of RWOM. The first study objective was to develop a database that documented the occurrence of white oak mortality within Arkansas, Missouri, and Iowa and associated site characteristics. The second study objective was to characterize insect pests and fungal pathogens associated with declining white oak at two Ozark study locations in Missouri, with particular emphasis on Phytophthora cinnamomi. As part of objective two, the physical distribution of mortality within stands was documented along with associated site characteristics.
Parent Publication
Citation
Reed, Sharon E.; English, James T.; Muzika, Rose Marie. 2016. Chapter 10: Investigation of Rapid White Oak ( Quercus alba ) Mortality within the Ozark Plateau and Adjacent Forest-Prairie Transition Ecoregion ( Project NC-EM-B-13-01). In: K.M. Potter and B.L. Conkling, eds., Forest Health Monitoring: National Status, Trends and Analysis, 2015. General Technical Report SRS-213. Asheville, North Carolina: U.S. Department of Agriculture, Forest Service, Southern Research Station. p. 127-133.