The exotic Brazilian peppertree is a serious invader of both disturbed and natural areas in central and south Florida, forming fast-growing, impenetrable thickets that dominate entire ecosystems. Brazilian peppertree has been targeted for biocontrol, and two defoliating insect species may eventually be released. This study was done to consider the possible effectiveness of defoliating biocontrol agents. The research investigated the effects of different frequencies of defoliation on height, crown diameter, and berry production of young Brazilian peppertrees. All the foliage was manually clipped from 36 trees in field plots once or twice per year for ≥ 1 yr. The effect on berry production of clipping 100% of the leaves from scattered individual branches of one large Brazilian peppertree was also examined. Trees that were completely defoliated five times at 6-mo intervals were significantly smaller and produced significantly fewer fruits than undamaged controls. Plants defoliated one time only, two times in 1 yr, and two times in each of 2 yr were comparable to the undamaged controls. From this simulated herbivory study, we infer that multiple defoliations by insect defoliators have the potential to significantly suppress the growth and fruit production of Brazilian peppertree in Florida.

Nomenclature: Brazilian peppertree Schinus terebinthifolius Raddi SCITE.