Geronimo Creek, a perennial creek, is fed by natural springs and a tributary, Alligator Creek. We selected two 100-foot sections along the creek that showed moderate erosion along the stream banks. We selected the upstream section for the restoration of native vegetation and the downstream section as the control site that will not undergo restoration.
Vegetation is an important aspect for stream bank stabilization. Roots help hold the soil in place reducing erosion. The above-ground portion of vegetation slows down floodwaters, dissipating the energy and allowing filtration of sediments and debris. Riparian corridors consist of a variety of species that are designated as obligate, facultative wet, facultative and upland. Obligate species grow right at the water’s edge where they survive with their roots in constantly inundated or saturated soil. Facultative wet species can grow slightly upland from the obligate species. They prefer saturated soils with seasonal inundation. Facultative species grow further up the banks of streams in slightly saturated to upland soils with tolerance to occasional flooding. Upland species prefer unsaturated soil.
The variety of species planted at the site include cardinal flower (Lobelia cardinalis), obedient plant (Physostegia virginiana), Emory’s sedge (Carex emoryi), creeping spikerush (Eleocharis montevidensis), beaked spikerush (Eleocharis rostellata), scouringrush horsetail (Equisetum hyemale), white star sedge (Rhynchospora colorata), Cherokee sedge (Carex cherokeensis), purpletop tridens (Triden flavus), Texas blue grass (Poa arachnifera), Leavenworth’s sedge (Carex leavenworthii), stream sedge (Carex blanda), creek sedge (Carex amphibola), inland sea oats (Chasmanthium latifolium), Turk’s cap (Malvaviscus arboreus), roughleaf dogwood (Cornus drummondii) and black willow (Salix nigra).
We placed jute matting along the steeper banks to reduce erosion during the planting and establishing of the vegetation.
On March 21, 2018 our team and volunteers from the local Master Naturalist and Master Gardener chapters planted over half of the native riparian vegetation at the restoration site. A second planting day occurred on April 7, which included our team and another group of volunteers associated with the Geronimo Creek Stream Cleanup, who helped plant the remaining vegetation. We are taking photos to track the progress over time at both the control and restored sites.