Larval mosquito production was monitored for 16 months in the furrows of a 13.4-ha citrus grove in east-central Florida used for disposal of secondary-treated sewage effluent. Twenty-one species of mosquito were collected, and the 2 most abundant species were Culex nigripalpus and Aedes vexans. An unplanned removal of all brush and trees from the site during the study resulted in an overall decline in larval production, but species diversity remained the same.