Longleaf Pine Understory Restoration in Camden, SC

Elizabeth Johnson, Adam Smallridge, Corrina McLeod, and Jackson Smith


Various studies have shown that the environmental conditions of an area can influence the morphology of a plant species’ local population, thus increasing survivability. In restoration ecology, this theory should be considered when re-establishing vegetation in an area.The Historic Camden Society is currently working to restore acquired lands to the historic ecosystem type of longleaf pine savanna at the Camden Battlefield and Longleaf Pine Preserve. Camden is located in the Carolina Sandhills, a region characterized by coarse, sandy, nutrient-poor soils and semi-frequent groundfires. A primary goal of this study is increasing the local population of little bluestem (Schizachyrium scoparium (Michx.) Nash), a bunchgrass that is vital to maintaining the necessary fire regime. Locally collected and commercially produced (Roundstone Native Seed Company) seeds were grown in a greenhouse experiment to assess any variation in growth rate or developmental patterns.This data shows that there is a significant difference between the growth habit of each source, with Roundstone seeds producing overall larger plants. These findings provide a better understanding of the adaptive differences in these little bluestem populations, and support the theory of ecotypic variation.


Göte Turresson coined the term “ecotype” in 1922, which is used to describe a variation of a species that is adapted to a particular location or site (Quinn, 1978). Since the creation of the ecotype concept, most researchers have evaluated the presence of ecotypes based on morphological, physiological, and ecological differences between populations. Numerous ecotypes can exist within a species, and drastically different or distant environments are not always needed to produce them (Snaydon, 1970). 

An area with extreme environmental conditions that may cause ecotypic variations in its local plant populations is the Carolina Sandhills. The Sandhills, a region comprised mostly of sandy and clay sediments, reaches into multiple counties of South Carolina, and into the neighboring states of Georgia and Virginia (Murphy, 2016). The quartz sands are low in nutrients and extremely permeable, which leads to leaching by rainwater. This leaching can cause the soil to become infertile and acidic. This, combined with the arid climate of Camden (Weather Spark) makes for a harsh and demanding environment, where only hardy and well-adapted plants can grow. Schizachyrium scoparium, commonly known as Little Bluestem, is among these plants. 

Little Bluestem is extremely adaptive to its environment, able to thrive in sites that receive anywhere from 10” to 60” mean annual precipitation and in plant hardiness zones ranging from 3 to 9 (Tober, 2013). As such, it is found all throughout the United States, and in some areas of Canada. The reason for its success is likely its high phenotypic plasticity, which allows it to develop into new ecotypes (Roos, 1977).

The Historic Camden Society is located in the Sandhills of South Carolina, and has been working on restoring a longleaf pine forest to its former glory. Little bluestem is essential to the longleaf pine ecosystem because of its ability to facilitate the ignition and spread of fire in the understory that help maintain a diverse community of vegetation (Landers 1991). In this study we are looking into the success of little bluestem seeds from both a local longleaf community and those commercially produced. We expect to see a difference between the growth patterns of these two varieties of seeds, with the local seeds being more adapted to the poor soil by having a larger root to shoot ratio. This would enable the plants to have more access to soil moisture and nutrients by increasing the surface area of the roots. 

Materials and Methods

Figure 1. Pictures of the potted plants in a controlled greenhouse environment (18-27ᵒC) with CAM plants on the left and RS plants on the right.  40 pots were split evenly between RS and CAM stock with 5 to 10 seeds per pot. Plants were kept on a frequent watering schedule with consistent daily or every other day check-ins.

Figure 2. An example of the un-potting and root cleaning processes of randomly selected samples for further analysis. These processes took place approximately every 3 weeks. A total of 6 plants (3 from each stock) were randomly selected and processed for measuring.

Figure 3. Once unpotted and cleaned, plants were measured with a ruler (in millimeters) before being dried for approximately 48 hours at 65ᵒC.  Dried plants were cut with a razor at the crown to weigh above and belowground biomass parts separately using a fine scale balance (Oahu’s Model AS120).

Figure 4. These two plants have been unpotted and are drying while waiting to be measured for both weight and length. RS plant is on the left, CAM plant on the right.


Figure 5. A comparison of total length (mm) of the commercially produced Roundstone seed stock and the locally collected Camden seed stock. Total length is defined as from shoot (leaf) tip to root tip. Roundstone plants were consistently longer than Camden plants, and these results were significantly different (p=0.046).

Figure 6. A comparison of the average total weight (g), after drying, of the commercial Roundstone seed stock and the locally collected Camden seed stock. Each measurement showed Roundstone plants to be heavier, but the data was not significant.

Figure 7. A comparison of the root-to-shoot length ratio (mm) of the commercial Roundstone seed stock and the locally collected Camden seed stock. The first data collected at 5 weeks showed Camden plants having a 3x larger ratio than Roundstone plants. Throughout the duration of the experiment Camden plants consistently showed a larger root-to-shoot ratio, but the data was not significant.


The importance of this experiment to Camden’s restoration project cannot be overstated, as choosing the right seed source will increase the bluestem’s chances of success. We believe that it is important to choose the seed source that will produce the highest root-shoot ratio. This will likely increase their chances of survival, because more of their biomass is below ground, where they will be protected from low-intensity surface fires. Their survival will, in turn, provide more fuel for future fires, encouraging frequent surface fires, which is the fire regime commonly found in longleaf pine forests (Carrey, 1992). Their lengthier roots will also be more adept at reaching nutrients and water deep within the soil, which is largely dry and nutrient-poor (Murphy, 2016). This will allow them to seek out resources to recover from the frequent fires of a longleaf pine forest.

One might notice that, over time, the root-shoot ratio of the two seed sources tend to approach each other, becoming more comparable. However, during the earlier stages of the Camden seed source’s life, the root-shoot ratio is significantly larger than that of the Roundstone (RS) seed source. We believe that this pattern will make all the difference. A plant is most vulnerable to harm during the earliest stages of its life (Brainpop), so in an environment where fire is frequent, it is likely that even a mild surface fire would eliminate a population of little bluestem before it could establish and grow. The local seed source, with its large amount of biomass below the soil surface, would therefore be more likely to survive a fire that would occur early in its life. 

It is also worth noting that the RS seed source produces more biomass overall than the Camden seed source, so it is likely that, even with more of its biomass exposed, the RS seed source will still survive due to its sheer size. Although this may seem promising, the root mass that the RS plants lack could be the deciding factor in whether or not the resulting population of little bluestem is successful. The local seeds will be able to extend their roots into the most nutrient-dense parts of the soil and capture all the energy they need from below ground while their leaves repair themselves. In the case of the RS seeds, after a surface fire the plant would rely heavily on its small roots and the minimal amount of leaves it has left to supply it with the necessary nutrients to repair itself. For this reason, we believe that the best option is the local seed source. 

A comparison of root lengths from March 10, 2021. A plant from the Camden seed source is on the left, and a plant from the Roundstone seed source is on the right. In a controlled environment with sufficient soil nutrients and water, the lengths of their roots are quite similar. Climate conditions in Camden, however, are not as favorable, and a field experiment would show different results.

Figure 8. A comparison of root lengths from March 10, 2021. A plant from the Camden seed source is on the left, and a plant from the Roundstone seed source is on the right. In a controlled environment with sufficient soil nutrients and water, the lengths of their roots are quite similar. Climate conditions in Camden, however, are not as favorable, and a field experiment would show different results. 


The decision of whether to use locally grown seeds or store bought seeds when planting a little bluestem understory in a longleaf pine forest is extremely important, especially in the Carolina Sandhills. As we discussed already, there are several extreme differences in the growth patterns of these seeds, the most influential being the early development of a good root/shoot ratio. This can mean the difference between success and failure for a young population of little bluestem. If the plants do not have a sufficient root system, even a mild surface fire could severely weaken or kill the plant entirely instead of just using the leaves as fuel. This would lead one to conclude that ecotype theory is a crucial factor to consider in similar restoration projects. Local populations will have adapted to the specific climatic and environmental conditions of the areas in question, which would make them the preferred choice to the “one size fits all” seeds obtained online.


  • Bragg, Louis H., and Calvin McMillan. “Ecotypic Differentiation within Four North American Prairie Grasses. III. Chromatographic Variation.” American Journal of Botany, vol. 53, no. 9, 1966, pp. 893–901. JSTOR, www.jstor.org/stable/2439812. Accessed 28 Jan. 2021.
  • Carey, Jennifer H. 1992. Pinus palustris. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/tree/pinpal/all.html [2021, March 27].
  • Landers, J. Larry, and D. D. Wade. “Disturbance influences on pine traits in the southeastern United States.” Proceedings of the Tall Timbers Fire Ecology Conference. Vol. 17. Tall Timbers Research Station Tallahassee, FL, 1991.
  • Parks, Noreen. “Restoring a Disappearing Ecosystem: the Longleaf Pine Savanna.” PNW Science Findings, May 2013, pp. 1–6. 
  • “Plant Life Cycle Background Information for Teachers and Parents.” BrainPOP Educators, https://educators.brainpop.com/lesson-plan/plant-life-cycle-background-information-for-teachers-and-parents/. Accessed 28 Mar. 2021.
  • Quinn, James A. “Plant Ecotypes: Ecological or Evolutionary Units?” Bulletin of the Torrey Botanical Club, vol. 105, no. 1, 1978, pp. 58–64. JSTOR, www.jstor.org/stable/2484264. Accessed 18 Jan. 2021.
  • Roos, Frederick H., and James A. Quinn. “Phenology and Reproductive Allocation in Andropogon Scoparius (Gramineae) Populations in Communities of Different Successional Stages.” American Journal of Botany, vol. 64, no. 5, 1977, pp. 535–540. JSTOR, www.jstor.org/stable/2442001. Accessed 23 Jan. 2021.
  • “ Sandhills Fact Sheet.” Sandhills Fact Sheet, Savanah River Ecology Laboratory, University of Georgia, archive-srel.uga.edu/outreach/factsheet/sandhills.html. 
  • Snaydon, R W. “RAPID POPULATION DIFFERENTIATION IN A MOSAIC ENVIRONMENT. I. THE RESPONSE OF ANTHOXANTHUM ODORATUM POPULATIONS TO SOILS.” Evolution; international journal of organic evolution vol. 24,2 (1970): 257-269. doi:10.1111/j.1558-5646.1970.tb01759.x
  • Springer, T. “Variation for Canopy Morphology in Little Bluestem.” Crop Science, vol. 52, no. 2, The Crop Science Society of America, Inc, Mar. 2012, pp. 729–37, doi:10.2135/cropsci2011.03.0167.
  • Tober, D. and N. Jensen. 2013. Plant guide for little bluestem (Schizachyrium scoparium). USDA Natural Resources Conservation Service, Plant Materials Center, Bismarck, North Dakota 58501
  • “WeatherSpark.com.” Average Weather in Camden, South Carolina, United States, Year Round – Weather Spark, Weather Spark, weatherspark.com/y/18861/Average-Weather-in-Camden-South-Carolina-United-States-Year-Round.