Surveys of TBW field populations in the Mid-South and Texas cotton-growing areas in 1993 indicated different levels of susceptibility to CURACRON^® but no instances of resistance. Baselines (LC50 and LC95 levels) were determined for adult vial tests, larval vial tests, leaf dip tests, and spray table tests. Adult vial bioassays support the 10 and 20 g discriminating doses for profenofos for the purpose of monitoring field populations. These doses are based on susceptible populations only.