Invasive exotic plants are considered as a form of biological pollution that threatens natural habitats worldwide. Once established the exotic plants are extremely difficult and expensive to control. Brazilian peppertree (Schinus terebinthifolius Raddi) is listed as one of Florida's worst noxious weeds and it is native to Brazil, Argentina and Paraguay. Over 3,000 ha of Brazilian peppertree infestation in an area known as the “Hole-in-the-Donut”, (HID) within the Everglades National Park (ENP) has occurred. Biological control by using carefully selected indigenous pathogens can be a useful tool in the invasive species management in sensitive habitats. As a first step, we have initiated studies to discover and develop potential native microbial biocontrol agents of Brazilian pepper. Fungal and bacterial pathogens were isolated from diseased pepper trees and initially tested using detached leaf assay. Selected fungal and bacterial pathogens were screened for infection and disease severity in the greenhouse. Disease symptoms (leaf spots, chloroses, necroses, and defoliation) were evaluated to determine the potential for weed control. In the initial trial plant inoculation resulted in low levels of disease symptoms, followed by slow recovery of inoculated plants. There were limitations in establishing infection using promising pathogens that were isolated from most severely affected peppertrees. To further optimize the inoculation procedure, studies on augmentation of inoculum using compatible humectants and adjuvants to maximize infection are also being evaluated. Development of standardized procedures to assess indigenous pathogen potential would be useful for conducting large-scale screening and also for determination of effective biocontrol pathogen/s.