An assessment of native bamboo (Arundinaria gigantea) establishment after the removal of an invasive exotic shrub (Ligustrum sinense) in a southeastern US riparian forest

Giant cane (Arundinaria gigantea) was once one of the most abundant plants in wetlands and riparian areas throughout the Southeastern U.S. However, giant cane stands (canebrakes) have become increasingly rare and there is much interest in utilizing giant cane to improve stream restoration efforts. The primary objective of this research is to evaluate the use of giant cane for stream restoration, especially in areas that contain monotypic stands of exotic invasive plants. Giant cane's ability to rapidly expand via clonal growth indicates that it might be able to compete with the many dominant exotics that hinder restoration efforts in the region. Clumps of giant cane were transplanted into areas both dominated by and recently cleared of Chinese privet (Ligustrum sinense), a widespread invasive exotic shrub. A randomized split-plot experimental design was established with nine replicates of two factors (privet, cane planting) each at two levels (privet & privet removal, cane & no cane, respectively). We measured cane survival and growth (clump area, new culms, culm height, and culm diameter), privet recruitment (number and height of privet seedlings), light availability, and percent cover of all species. Cane survival was high (93%). Privet removal resulted in an increase in light availability, number of new cane culms, diameter of new cane culms, and growth of privet seedlings. However, there was no privet removal effect upon cane height (mean: 61.1±1.7 cm) or number of privet seedlings (mean: 22.7±6.2 seedlings/m²). During this first growing season, giant cane establishment was very good; these results demonstrate great potential for restoring canebrakes and utilizing giant cane to improve riparian restoration efforts in the Southeastern U.S.