Plant Industry - Plant Protection Section - Sweetpotato Weevil Program

Surveys

Field surveys.  NCDA&CS sets traps in sweetpotato fields in North Carolina to monitor for sweetpotato weevils from August to October.  Green Funnel Traps are used and set with a male-specific pheromone lure and a kill strip at a density of one trap for every 10 acres or minimum of two traps per field following the protocols established by the Southern Plant Board committee.  Traps are set and left in the field for three weeks, pulled and checked for weevils and the data collected using apps in mobile devices (tablets). Data collection using mobile technologies has greatly improved NCDA&CS efficiency in these survey programs.  In 2020, 12,411 traps were set in sweetpotato fields in NC (Table 1) and no weevils were detected.

Table 1.  Traps set in sweetpotato fields in North Carolina during the 2020 survey season

Storage and processing facilities.  The movement of sweetpotatoes from production areas within the state and from other states into NC is one of the most important pathways of introduction of sweetpotato weevils into NC.  Storage and processing facilities are monitored all year during the sweetpotato storage season.  Bucket traps (or Universal Moth Traps) are used because of their higher efficiency in trapping and retaining weevils.  Traps are set at a minimum of 2 traps per storage facility with one trap inside and one outside and, a maximum of 3-4 traps according to the size and complexity of the operations.

Micropropagation and research facilities.  Sweetpotato micropropagation facilities (greenhouses) are important to propagate virus indexed and disease-free material necessary for planting high quality sweetpotato cuttings in NC production fields.  These facilities are monitored seasonally following the micropropagation protocols.

To report a sweetpotato storage, processing, research facility, or production field without traps, please phone our toll-free number at 1-800-206-9333 or report by email: newpest@ncagr.gov

Specialty surveys.  Although the NCDA&CS does not want to discourage the general public from planting sweetpotato plants in their gardens, educational or demonstration plots, we strongly suggest you contact the Plant Pest Specialist (PPS) in your area to monitor your plot for sweetpotato weevils.  NCDA&CS PPS will set and service traps in these small operations at no cost to the public.