Biological control of the invasive weed Schinus terebinthifolia (Brazilian Peppertree): a review of the project with an update on the proposed agents.
Schinus terebinthifolia (Brazilian Peppertree) is a South American plant that has become invasive in many countries around the world. It was introduced into the US about 100 years ago as an ornamental. Escaping cultivation, it now occurs in Alabama, Florida, Georgia, Texas, California, and Hawai'i. This species is one of the most invasive weeds threatening agriculture and natural areas in the Southeast. Efforts to manage Brazilian Peppertree populations with biological controls began in Hawai'i in the 1950s and resulted in the release of 3 insect species. However, the control agents have had minimal impact, and the weed continues to be a difficult problem. More recently, our international team of collaborators has discovered and tested numerous new species of potential biological control agents. These species attack different plant tissues and include defoliators, sap-suckers, stem borers, and leaf- and stem-gall formers. Despite difficulty finding an agent sufficiently specific for field release in Florida, we have narrowed the field to 2 promising species, the thrips Pseudophilothrips ichini (Hood) and the foliage-gall former Calophya latiforceps Burckhardt. Results of no-choice and choice trials conducted overseas and in quarantine indicate that both species will safely contribute to the control of this invasive weed. Herbivorous feeding by immature and adult individuals of both herbivore species stunt growth, distort leaves, and should reduce reproductive output of Brazilian Peppertree.