Utilizing goats to manage sericea lespedeza for restoration of native warm season grass pastures

By Dr. Kendra Esparza Harris, Dr. Harley Naumann, and Dr. Ashley Conway-Anderson

Sericea lespedeza (Lespedeza cuneata) is an invasive perennial legume that negatively impacts native plant species in Missouri pastures. This non-native species reduces the amount of desirable forage in pastures, decreases cattle grazing efficiency, and is particularly challenging to eliminate because it evades common control strategies. However, goats and sheep tolerate (and in some cases, prefer) sericea lespedeza as a forage source, and may potentially benefit from its anti-parasitic properties due to the high condensed tannin content.  

Center for Agroforestry and MU CAFNR researchers assessed the impact of goat grazing stocking densities on the abundance of sericea lespedeza, and studied the subsequent change in the proportion of forage species in warm-season pastures. This extension project also sought to see if grazing sericea lespedeza could affect the presence of gastrointestinal parasites. At the MU Land of the Osages Research Farm, goats grazed pastures at high (14-head), medium (7-head), and low (4-head) stocking densities from July to October (2021) with pasture composition and fecal egg counts measured before and after grazing. 

Grazing sericea lespedeza, regardless of stocking density, did not affect goat gastrointestinal parasites. We suspect this finding varies from typically observed reports because the measured condensed tannin content of sericea lespedeza in our study was much lower than in other studies. This suggests that the anti-parasitic effect of grazing sericea lespedeza has a biological threshold for reducing internal parasites, though further research is needed to identify what that threshold might be.  

Goat grazing densities also did not decrease the abundance of sericea lespedeza. However, abundance of other vegetation groups including warm-season grasses, grass-like species, and forbs changed over the years following grazing (2021-2024). Warm-season grasses increased (11.8 to 36.1 percent), and grass-like species and other forb species decreased (19.7 to 0.78 percent and 17.8 to 9.5 percent, respectively).

Although the abundance of sericea lespedeza wasn’t affected, the long-term changes in plant populations suggest that the selective diet of grazing goats can impact the competition between plant groups for several years after grazing. Given how resilient and invasive sericea lespedeza is, similar grazing practices could make way for other plant groups like warm-season grasses to successfully compete for space.

Our findings suggest that even in pastures grazed by goats at high stocking densities, multiple years of grazing (with and without additional management strategies) may be needed to have a considerable long-lasting impact on reducing sericea lespedeza. This corresponds well with other research that suggests that goat grazing can be an effective land management tool for controlling invasive species such as sericea lespedeza. 

This research project was funded by SARE. For more information, check out these SARE project final reports:

https://projects.sare.org/sare_project/gnc20-314/

https://projects.sare.org/sare_project/gnc22-347/