Deer Deterrent Trials to Improve Plant Establishment in Remote Natural Areas

For more than 25 years the State Botanical Garden of Georgia (SBG), and our partners in the Georgia Plant Conservation Alliance (GPCA), have been working to augment natural populations of imperiled species across Georgia by propagating plants and returning them to strategically selected sites in situ for conservation purposes. Additionally, we work with landowners, public and private, to restore degraded habitat through management and outplanting native species. The biggest obstacle for establishing plants for conservation and restoration in the southeast is white-tailed deer herbivory. Many techniques exist for deterring deer herbivory, but each has significant deficiencies. Deer deterrent sprays must be reapplied regularly. Cages and fences need regular maintenance to remove debris and repair damage from animals and weather. Installing cages and fences in natural areas can be prohibited by cost and labor. We need a simpler way to protect plants from deer. To investigate a forgotten heirloom technique of placing spikes around plants, we are conducting an establishment experiment in natural areas at the SBG where we have an overabundance of white-tailed deer. We are testing establishment of an S1 endangered wildflower, Silene regia, and a common wildflower, Symphyotrichum georgianum, both known to be heavily browsed by deer on our property. Using a split-plot randomized block planting design, we are comparing three treatments for deterring deer herbivory; cages, companion planting, and bamboo spikes. Data will include measures of flowering, dry weight and monitoring deer behavior with wildlife cameras. If spiking technique deters deer herbivory, this simple, light weight, and inexpensive method could have a significant impact for in situ plant conservation and restoration, as well as gardening in areas with over-abundance of white-tailed deer.