There is growing interest in whether invasive species may be controlled by utilizing management strategies that target vulnerable life stages. We manipulated the timing of fire and measured its effects on sericea lespedeza germination and seedling survival. Although fire strongly decreased germination in the laboratory, fire increased germination under field conditions. Additionally, fire caused small decreases in seedling survival in the field. Therefore, controlled burns are likely to encourage spread of sericea lespedeza and are unlikely to effectively control this invasive species. Although targeting vulnerable life stages is a promising strategy for invasive species control, our results illustrate that system-specific studies may be needed to unravel potentially complex interactions between biotic and abiotic factors before effective control strategies can be devised.

Nomenclature: Sericea lespedeza, Lespedeza cuneata (Dum. Cours.) G. Don

Management Implications: Sericea lespedeza is a noxious invader capable of suppressing native species in grasslands and prairies in the Great Plains. Currently, repeated herbicide application is the only effective method of controlling sericea lespedeza; however, herbicides are cost prohibitive for many land managers. Fire has been considered as a potential management tool for controlling this weed but it is not currently recommended because adult plants may resprout. However, controlled burns might be useful to control recolonization from seed after adult plants have been killed with herbicides. Our results show that burning seedlings in the growing season immediately following germination slightly reduces sericea lespedeza survivorship but creates a large flush of germination that more than offsets this reduction in survivorship. While it remains possible that other burning treatments may reduce the spread of this noxious weed, the treatments we tested suggest that fire will encourage sericea lespedeza invasion.