Recovery of a prairie plant community following sericea lespedeza (Lespedeza Cuneata) removal: Testing for a soil legacy effect
Sericea lespedeza (Lespedeza cuneata) is an invasive legume threatening plant communities in the southeastern and southcentral United States. In addition to reducing native species abundance, current evidence suggests that L. cuneata invasion may alter soil conditions in host communities. If correct, L. cuneata may create a soil legacy effect that impacts community recovery, even if control measures have effectively removed L. cuneata. I examined the recovery of a prairie plant community in Jefferson county, Kansas to determine if the historical presence of L. cuneata affected 1) the relative abundance of all species and 2) the colonization of native species in the community four years following L. cuneata removal. To address this, L. cuneata seeds were sown into 300 plots at a wide range of densities (0 to 10,000 seeds m-2 ) under different combinations of simulated disturbance and soil fertilization. After a three-year establishment period, the percent cover and stem density of L. cuneata was recorded, and the community was burned and sprayed with herbicide to eliminate L. cuneata. Fertilization and disturbance treatments were discontinued, and thirteen native forb species were sown into all plots. The stem density of all sown species was recorded annually over a four-year recovery period, and the percent cover of all species present was recorded in the fourth year of recovery. Analysis of community data in response to the historical presence of L. cuneata did not indicate the presence of a soil legacy effect. Although the relationship between community species cover and the historical cover of L. cuneata was significant in some cases, the variation explained by these comparisons was quite low. Similarly, the colonization of sown native species in the community was unrelated to the historical cover of L. cuneata. These results indicate that L. cuneata does not create a soil legacy effect if effectively controlled within the first three years of invasion, regardless of initial density.
Thesis (M.S.)--Wichita State University, Fairmount College of Liberal Arts and Sciences, Dept. of Biological Sciences
- Master's Theses