Sustained management is necessary to suppress Sericea lespedeza (Lespedeza cuneata) population growth in a landscape of tallgrass prairie reconstructions

Abstract

Introduction: Sericea lespedeza (Lespedeza cuneata) is a nitrogen-fixing legume that is native to Asia and was promoted in the central United States for forage, wildlife habitat, and to mitigate erosion and mine spoils. It has since become a high-impact invasive plant,especially in tallgrass prairie ecosystems. Traditionally, herbicide is the common tool to control Sericea lespedeza’s spread and manage its impact; however, herbicide treatments come at a cost to other restoration efforts.

Objectives: This research was conducted to evaluate the effectiveness of management to control Sericea lespedeza populations within a chronosequence of reconstructed tallgrass prairies. Methods: We compared the difference in Sericea lespedeza coverage across 98 (25 m²) paired plots from 2019 to 2023 representing (1) managed and (2) management-excluded treatments along with differences in the Sericea lespedeza seed bank after 4 years.

Results: Findings from this study suggest that Sericea lespedeza populations continue to grow in the absence of management, increasing to 13 times their original densities, while populations in areas of sustained management remained stable around 2–5% coveragewith year-to-year variation. Without management, the Sericea lespedeza soil seed bank was also five times more abundant. Older prairie reconstructions were more resistant to increases in Sericea lespedeza abundance but were not immune. Results also suggest that management may negatively impact forb populations, but without management both forb and graminoid populations declined.

Conclusions: This study highlights the importance of maintaining and prioritizing resources for the long-term control of aggressive invasive plants.

Implications for Practice: In prairie restorations and reconstructions, the need for frequent Sericea lespedeza control preempts resources that could otherwise be used for other habitat improvements. Reconstruction approaches did not have a noticeable effect on the abundance of Sericea lespedeza. Maintaining sustained control of Sericea lespedeza is important for reducing impact on plant communities and suppressing its population growth, regardless of reconstruction age. Older reconstructions were more resistant to increases in Sericea lespedeza, but if undetected and unmanaged, existing populations may increase. A skip year of control may be possible in prairie reconstructions that are well developed, where Sericea lespedeza is scarce, and where robust monitoring programs can quickly respond.

Citation

Pile Knapp, Lauren S.; Knapp, Benjamin O.; Crouch, Connor D.; Newbold, Chris; Demand, Jeff. 2026. Sustained management is necessary to suppress Sericea lespedeza (Lespedeza cuneata) population growth in a landscape of tallgrass prairie reconstructions. Restoration Ecology. 34(3): e70250. 13 p. https://doi.org/10.1111/rec.70250.