Dendroecological Potential of Appalachian Riverscour Woodland Trees

Appalachian riverscour woodlands are intermittently flooded areas along high-energy rivers characterized by exposed bedrock and poorly developed sandy soils, high plant diversity, and scattered and stunted trees.  These sites can be negatively impacted by dam construction and alterations to river hydrology, trampling associated with riverside recreation activities, and non-native species.  In West Virginia, little is known about the development of riverscour woodlands or the growth and hydroclimate sensitivity of associated tree species.  In this exploratory study, our objectives were to evaluate our ability to crossdate riverscour woodland trees (i.e., assign accurate calendar years to annual growth rings) as well as determine stand structure and tree establishment patterns at one site along the New River in Fayette County, West Virginia.  In addition, for two species, Ulmus americana and Diospyros virginiana, we examined annual growth trends and relationships between tree growth and monthly hydroclimate, including streamflow, precipitation, and Palmer Drought Severity Index (PDSI).  Seventy-three percent of all ring-width measurement series were crossdated, but results were mixed across species.  Most trees were less than 50 years old and no trees established before the late 1940s.  Both U. americana and D. virginiana were highly sensitive to April–August hydroclimate, but differed in response to previous year moisture availability.  These findings provide new direction for the use of riverscour woodland trees in future dendroecological studies.