Survey of weed flora in central and south Florida tomato fields

Abstract The first-ever survey of weed flora near season end in commercial tomato ( Solanum lycopersicum L.) fields in central Florida was conducted during the 2021 to 2022 field seasons. Forty-seven fields were surveyed, which represents a total of 593 ha. Fumigation occurred on 94% of all surveyed fields, and fertility and water were applied via drip tape on 77% of the fields, with furrow irrigation occurring on the remaining fields. Preemergence herbicides were applied under the plastic mulch on 74% of the fields, and herbicides were applied in all row middles. A total of 62 weed species escaped weed management and were identified during the season-end survey. Purple nutsedge ( Cyperus rotundus L.), common purslane ( Portulaca oleracea L.), goosegrass [ Eleusine indica (L.) Gaertn.], and smooth crabgrass [ Digitaria ischaemum (Schreb.) Schreb ex. Muhl.] occurred in the row middles of 74%, 70%, 68%, and 55% of all fields surveyed, and the same four species also had the highest relative abundance. Purple nutsedge ( Cyperus rotundus L.), E. indica , P. oleracea , D. ischaemum , Florida pusley ( Richardia scabra L.), and cutleaf evening primrose ( Oenothera laciniata Hill) occurred in the transplant holes of 60%, 34%, 28%, 23%, 19%, and 15% of all fields surveyed. Cyperus rotundus had the highest relative abundance in the transplant holes by a large margin, followed by O. laciniata. Moving forward, this information will help tomato growers, extension agents, and weed scientists identify the key weeds that are likely to be problematic on tomato farms and will guide future weed management research programs.