Savanna Remnant Restoration Study (2016-2020): plot locations and understory species abundance

The Savanna Remnant Restoration Study (SRRS) was conducted at the Savannah River Site (SRS) near New Ellenton, SC. Seven treatments were applied to remove overstory hardwoods via cutting and various herbicide and non-herbicide methods in an effort to control hardwood regrowth and increase abundance and diversity of remnant savanna species, thereby restoring the native plant community. Two types of understory vegetation data were collected to evaluate treatment responses: (1) nested quadrat data to estimate understory species density (i.e., number of species versus sampled area), diversity, and equity, and (2) line transect data to estimate changes in understory species cover. Data were collected in the fall prior to treatment (2016) and annually for four years after treatment (2017-2020). These data were collected prior to a planned program of prescribed fire at 3-5 years intervals - a regime that is considered necessary for the establishment and maintenance of longleaf pine savanna species.
Previous research on the SRS has identified mature hardwood forests as potential sources of remnant savanna vegetation that, in association with longleaf pine woodlands, once dominated much of the southeastern U.S. Tillage farming from the 1880's until 1950 eliminated much of the savanna woodland communities once present at the SRS. The objective of this research was to test the hypothesis that directed herbicide placement treatments are effective at restoring the native understory community with minimal collateral damage relative to hardwood cutting alone, cutting plus mechanical shredding of logging residues, or cutting plus broadcast herbicide application.
For more information about this study and these data, see Harrington et al. (2021).