Restoring pine savannas using wiregrass transplants
There have been abundant studies on restoring wiregrass from both seeds and plugs, but only one ingenious study has examined the utility of transplanting wiregrass tussocks (also called clumps). During the dormant season of 1981, Dr. Bruce Means initiated a study to excavate 159 wiregrass tussocks and moved them to a nearby old field pine community that had no wiregrass. Before planting the wiregrass tussocks, Dr. Means had the competing woody vegetation removed with a hoe, but the vegetation quickly regrew around the wiregrass after the tussocks were transplanted. Fortunately, he planted the wiregrass in organized rows to allow the plants to be easily revisited. Dr. Means hired Trina Mitchell to recensus the population in 1999, and Kevin Robertson supervised Anthony Laucevicious, a Deaf student from Gallaudet University, in censusing the population again in 2018. Here are the major findings from their study*:
One of the most interesting things about this study is that it shows wiregrass can be successfully transplanted. Wiregrass seeds and plugs can be prohibitively expensive, but if you have wiregrass on your property and the inclination to excavate and transplant it, you can create a population that will successfully grow and spread over time.
The density of plants started to level off over time. As wiregrass reproduces and grows, it reaches about 30 plants per 10 ft2 area. That is, if there is a greater density of small plants, they seem to self-thin as they grow, and if there are a smaller number of plants, then more plants fill in the area over time. In nature, we observe that wiregrass does not usually exceed this density. This is good news for restoration because you do not need to worry about planting at a natural density or using specific spacing between plants. Wiregrass will regulate itself to a natural density.
The authors also found that recruitment of new plants varied over the 37-year study. The plants did not recruit as much between the first and second sampling periods, which they tentatively attributed to drought conditions during the second interval. While the plants seem to eventually spread over the area with time, there will be year-to-year variation depending on the success of flowering and recruitment in different years.
I would like to know whether you can transplant part of a wiregrass plant. For instance, maybe it is unnecessary to excavate an entire wiregrass tussock, but rather a portion of the tussock would work. In that sense, it would be relatively simple (but likely still hard work) to move individuals from an area of high to low (or no) density wiregrass. As someone who has tried to excavate an entire wiregrass plant, I can tell you they have extensive root systems!
Let’s hope the authors revisit these plots in another 20 years to update us on the success of this restoration project!
Have you tried to transplant wiregrass plants on your property? If so, leave us a comment below. We would love to hear about your experiences!
*Data in graphs were derived from Table 2 in Laucevicius Jr, A.M., Robertson, K.M., Means, D.B., Mitchell, T.R., & Taylor, P.B. 2021. Expansion and population structure of transplanted Aristida beyrichiana (wiregrass) tussocks: results of a 37-year study. Restoration Ecology 29: e13404. PDF LINK
