Ericaceous shrub expansion as related to fire history in xerophytic pine-oak (Pinus-Quercus) stands of the Appalachian Mountains

Keywords: Ericaceous shrubs, Fire history, Kalmia latifolia, Mesophication, Pinus pungens, Shrub expansion
Abstract Type: Poster Abstract

Abstract

Shrub expansion is common in forests, but the role of fire suppression and other factors have not been widely investigated as they have in grasslands. In this dendroecological study, we explore the influence of fire suppression on mountain laurel (Kalmia latifolia) shrub expansion in dry pine-oak (Pinus-Quercus) forests in the Appalachian Mountains. The shrubs appear to have been uncommon until about 20–40 years after fire suppression began. Thereafter, they expanded to become extensive thickets. Mountain laurel expansion probably was abetted by chestnut blight (Cryphonectria parasitica (Murrill) Barr) and acid deposition that occurred in the mid-twentieth century. However, shrub establishment was asynchronous across multiple study sites; this probably would not have been the case if region-scale factors (chestnut blight or acid deposition) controlled expansion. Therefore, fire suppression was apparently the predominant factor permitting shrub establishment. Shrub cover may be controlled by prescribed fire in landscapes where frequent burning is possible.