2013 Missouri Oak Mast Survey Report
The Missouri Department of Conservation has conducted an annual survey of mast production since 1960. The majority of this data has been collected in oak-hickory forests located in five regions of central and southern Missouri (Figure 1). Individual, mature (i.e., potentially seed-producing) oaks are visually rated according to the number of developing acorns in crowns and classified as supporting high, moderate, low, or few to no acorns. A mast production index (MPI) is generated from this data to provide an estimate of the availability of oak mast, giving MDC and the public an indication of what is in store for mast-dependent forest wildlife during fall and winter.
The results of the 2013 MDC mast survey indicated that acorn production was fair to marginally good for red, white, and all oaks both regionally and statewide. This year’s total acorn production (i.e., all oaks combined) contrasts sharply with the estimate for 2012, which was the lowest recorded over the 53-year history of the mast survey. Total acorn production in 2013 was more than double the production observed in 2012. Low production in 2012 was likely due, in part, to the severe drought and record-setting high temperatures experienced during 2012. However, Missouri experienced a much milder growing season in 2013. Average monthly temperature and precipitation for the period of March to September were approximately 2ºF below and nearly 1 inch above the long-term average (1895-2010), respectively. Since oak reproduction is affected by weather, milder conditions in 2013 could partially explain the large increases in acorn production seen at state and regional scales.
Based on these findings, there could be above average oak mast available for Missouri’s wildlife this fall and winter.