Spatial Assessment of Meadow Vole Herbivory on a Replanted Agriculture Field in Mississippi

Abstract

Successful afforestation of fields formerly used for agricultural production is dependent upon manageable seedling mortality rates.  Animal herbivory can exacerbate mortality of planted seedlings beyond acceptable levels.  A study conducted at a planted site in Desoto County, Mississippi, of 1,440 bare-root seedlings comprised of Nuttall oak (Quercus texana Buckley), Shumard oak (Quercus shumardii Buckley), and swamp chestnut oak (Quercus michauxii Nutt.) exhibited high levels of mortality as a result of herbivory by meadow voles (Microtus pinetorum LeConte) seven years after planting.  Tree locations, according to planting, were analyzed using hot-spot (Getis-Ord Gi*) and cluster-outlier (Anselin Moran’s I) analyses to determine if a spatial pattern exists for herbivory by meadow voles.  Meadow voles accounted for 94 percent of the mortality on the planting site.  A spatial relationship was determined for motality caused by meadow vole herbivory, particularly for the Nuttall oak seedlings (i.e., cold spots).  Overall, it was determined that meadow voles favored Nuttall oak seedlings throughout the planting area over Shumard and swamp chestnut oaks.  Should animal herbivory lead to unacceptably high mortality for seedlings, this information will be useful to resource managers for the application of counter-measures to prevent increased mortality.