Larvae ofTabanus nigrovittatusMacquart,Chrysops fuliginosusWiedemann and C.atlanticusPechuman were recovered most often and in greatest abundance in regularly flooded areas of salt marshes with nearly uniform stands ofSpartina alternifloraLoisel (smooth cordgrass). Areas ofS. cynosuroides(L.) Roth. (giant cordgrass),Distichlis spicata(L.) Greene (salt grass), andJuncus roemerianusScheele (black needle rush) yielded decreasing numbers of tabanid larvae (in that order). In mixed vegetation, as the proportion of other vegetation increased andS. alternifloradecreased, the numbers of tabanid larvae declined