The once
dominant Arundinaria gigantea
(Walt.) Muhl. canebrake ecosystem has been
reduced to fragmented populations, trapped between increasing anthropogenic
development and closed canopy forests. This decline in the A. gigantea population has resulted in a
critically endangered ecosystem, impacting many species and making
reestablishment of canebrakes necessary for maintaining and enhancing
biodiversity in the southeastern United States. To facilitate
restoration of canebrakes, we compared historical and present distributions,
sampled remnant brake environments, and tested effects of environmental factors
(e.g., nutrients and light) on A. gigantea growth. For the latter, thinning sites were
established in existing cane populations and forest canopy reduced 60%, a field
experiment was set up to test effects of competition and nutrients (P, N, P+N)
on rhizome transplants, and a laboratory experiment was conducted to test light
(partial shading and full light) and nitrogen (0, 0.5, 1.0, 25, and 100 g/L)
effects on seedling growth. Additionally, a light response curve was conducted
to examine plant light usage (A. gigantea remained photosynthetically
active throughout the winter). Results indicated A. gigantea growth was enhanced with
increased light levels and nutrients, both N and P. Of particular interest was
increased root and rhizome biomass, which could be critical for improving
establishment and survival of plants to a restoration site. Historically,
canebrakes were more widespread, less fragmented, and occurred in a wider
variety of floodplain environments than their present distribution suggests.
Reduction of overstory canopy and transplants into
old fields were experimentally-supported management strategies for increasing
existing populations.