How working with SCA led to more than a normal internship
Author: Caroline Ritchey
Though known for its iconic longleaf pine and wiregrass pairing, the pine savanna is actually one of the most diverse and species-rich ecosystems in the Earth’s temperate zone.1 For the last 12 months, I had the pleasure of working in this unique ecosystem as an SCA intern with The Nature Conservancy in Georgia. However, this ecosystem is in a vulnerable state these days.
Between fire suppression and land loss, only 5% of the pine savannah remains of what was once an extensive part of the Southeastern United States. As a naturally fire-dependent ecosystem, the habitat needs fire to function at its fullest. Without understanding this, humans have attempted to keep fires in the forest to a minimum.4
A downward spiral has begun in the pine savanna as fire suppression increases hardwood encroachment, 1 preventing the forest from naturally burning in season. As the cycle continues, re-introducing fire into this ecosystem becomes harder, causing further encroachment that will irreparably change the ecological dynamics of the system.3 Solutions include reducing hardwood and increasing diversity by reintroduction of fire, mechanical means, or chemical means.2
One part of my job with The Nature Conservancy was to participate in prescribed burning to restore the habitat to a more natural state. My main focus was the endangered red-cockaded woodpecker, which we were hoping to release on site later in the year.
However, in some places, recurrent burns couldn’t control certain patches of persistent hardwoods. A few places in particular needed to be thinned to support rare species on our preserve.
Because I felt invested in this unique environment where I have had the joy of living and working for my term, I wanted to do something extra that would benefit the area and The Nature Conservancy.
My site supervisor and I agreed to help Moody Forest Natural Area by reducing hardwoods in the midstory of the pine savanna, on one of those problem spots (a 3.5 acre area) allowing me to research the chemical methods on site. I chose to perform a cost-benefit analysis of two chemicals using the application method of “hack-and-squirt” performed with a hand held-hatchet and a squirt bottle of the desired chemical.
Based on the concentration and soil activity of the costlier chemical, imazapyr, I predicted that it would be both quicker to apply and also more effective at killing hardwoods than the more common chemical, glyphosate. At the same time, I also hypothesized that imazapyr would have a greater negative impact on the surrounding plants. I then predicted that glyphosate’s labor-intensive application method would take longer to apply decreasing its cost-to-benefit ratio.
After designing my experiment, I spent two weeks treating the trees. I allowed a month to pass and then returned to analyze the results. I was surprised to find that imazpyr did not have as harmful of an effect on the surrounding plants as I first hypothesized.
I also found that it wasn’t as effective in reducing the hardwoods. Additionally, application time between the two chemical methods did not differ significantly. Based on my statistical analysis, glyphosate may be the most effective treatment for reducing hardwoods for habitat restoration.
The details of the experiment have the potential of informing land managers about safer methods of herbicide with minimal environmental impact. My goal is to submit my research to the Journal of Forest Ecology and Management where it can be available for researchers, land managers, and policy makers to consider. I am currently working to edit an article for submission by fall 2017.
Overall, I had a good experience working on this research project as it taught me more about data collection and field research design methods. It was also a time to learn and expand what I already “knew,” while putting aside preconceived notions.
I always had a “knee-jerk” reaction to the word “herbicide” and thought that it shouldn’t be used if we were seeking to preserve the environment. However, my time with The Nature Conservancy has taught me that, when used well, herbicide is an effective tool for land management and restoration.
I was able to actively participate in the release of red-cockaded woodpeckers on the preserve near the treatment site. My site supervisor has also benefited from the results of my study as he continues to work the preserve in my absence.
My research has stimulated questions about different herbicide methods he could try on the preserve as well as moved him to use glyphosate in other problem areas on-site. His response was a great re-assurance that what we are doing here is more than just academic but also practical and helpful and makes a difference.
- Kirkman, L. K., Mitchell, R. J., Helton, R. C., & Drew, M. B. (2001). Productivity and species richness across an environmental gradient in a fire-dependent ecosystem. American Journal of Botany, 88(11), 2119-2128.
- Oswald, B. (2014). Fire exclusion effects within the Pinus palustris communities of upland island wilderness, Texas. Southeastern Naturalist, 13(Sp5), 80-92.
- Rudolph, D. C., Conner, R. N., & Schaefer, R. R. (2002). Red-cockaded woodpecker foraging behavior in relation to midstory vegetation. The Wilson Bulletin, 114(2), 235-242.
- Tucker, J. W., Robinson, W. D., & Grand, J. B. (2004). Influence of fire on Bachman’s sparrow, an endemic North American songbird. Journal of Wildlife Management, 68(4), 1114-1123.
- Photo 1: Caroline participates in a prescribed burning to restore the habitat to a more natural state.
- Photo 2: The Georgia Department of Natural Resources in the process of banding red-cockaded woodpecker fledglings.
- Photo 3: A snapshot of the research Caroline designed.
- Photo 4: After Caroline’s research, the Georgia Department of Natural Resources returned to insert artificial red-cockaded woodpecker cavities near newly thinned areas.