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WBC Trapping Instructions

2018 Western Bean Cutworm Trapping Instructions and Supply List

Pheromone traps can be used to monitor for adult WBC moth presence and detect when peak moth flight occurs. Traps should be used in all regions of Ontario, not just the known hotspot areas of Bothwell and Tillsonburg as moths can be active anywhere corn and dry beans are grown. Traps cannot be used directly to determine when a spray is required but rather indirectly by identifying fields that are at risk and when scouting is required. Moths can be captured as early as June and peak flight typically occurs in late July, though this can be one week earlier or later in any given county depending on weather and other factors.  Shortly following peak flight is peak egg laying and when scouting is critical.


Trapping Instructions

  1. Register your trap sites at
  2. For each corn site, use 1 trap per field; for dry beans, use 2 traps per field.
  3. Traps should be monitored at least weekly starting in early June until late August/early September.As peak flight approaches, plan to monitor the traps more frequently so that there are fewer moths to count at one time and the moths are less likely to be deteriorated and difficult to ID.
  4. Mount the trap so that it hangs from a stake or T bar so that the trap is 4 feet above the ground (Figure 1).Figure 1. Green WBC bucket trap placed along the fields’ edge. Photo Credit: Jen Bruggeman, UGRC
  5. Position the trap on the prevailing wind side of the corn field, along the edge but not within the corn rows. This will help carry the pheromone plume into the field being monitoring and give a better indication of moth activity for that field. For dry beans, place two traps, each on opposite’s sides of the field. They can be positioned at the same height as corn, placed within the first few rows of the beans or along the field’s edge above low-lying weeds.
  6. One lure is placed inside the small cage area provided at the top of the bucket trap lid while the vapour strip is placed inside at the bottom of the bucket.  
  7. Check traps at least weekly, counting and discarding any moths captured within the bucket. Ensure that the moths counted are WBC. Large yellow underwing moths can be captured in these traps, especially early in the season and may be misidentified as WBC.
  8. Provide weekly trap counts for each location at . In return, interactive maps are created to help identify those areas at risk that require scouting.  Weekly maps can be found at OMAFRA’s AgMaps site at:,4846692.5603,-8017663.5582,5969399.6318,102100&muraadminpreview&mobileformat=false

Trap Supplies:  

For each WBC trap, you will need:

  1. Bucket or Universal Trap   
  2. WBC Pheromone Lures      
  3. Fumigant or Vapour strips
  4. 6 foot wooden stake or metal t-bar from your local lumber or hardware store


1. All Green Bucket or Universal Trap are the preferred trap for WBC, as milk jug traps are more labour intensive, often drying out of their antifreeze in hot weather, rendering the trap useless. Though not as cost effective as milk jugs, bucket traps can be used for multiple years. 

Two suppliers we have dealt with:

  • Ontario/Quebec supplier: distributions Solida


Make sure to order it in all GreenItem #301Y602

                  Make sure to order it in all Green – Item #IPS-G004 

2. Pheromone Lures

5 lures are required per trap per season.  Preferred WBC Pheromone Lure Brands include “Scentry” or “Trece”.  Change lures every 3 weeks, starting from June 1st until Sept 14th = 15 weeks/3 = 5 lures/trap/year.  Lures must be stored in the freezer prior to use and can be used next year if you have some leftover from the previous year.  It is cost effective to order a case of 12 or 25 lures and have them for next year too.

The lures are not listed on their website but they do carry Scentry brand lures for WBC. Contact Solida directly to order the correct lures

Scentry brand WBC Lures Item # SC-L206 - also available in cases of 12 lures

Trece brand WBC Lures Item # TR-3406 – also available in a cases of 25 lures

3.  Fumigant or Vapour Strips

These are plastic strips impregnated with an insecticide to kill the moths so that they do not fly away when you open the trap to count them.1 strip will last for at least 2 months.You can order them at distributions Solida so that there are no issues with getting it across the border.  If in a pinch, we have also gone to a local hardware store and purchased the Ortho Home Defense Strips for flies One Ortho Home Defense Strip can be cut into 1 inch wide strips and be enough for 5 traps.  Always use gloves when handling these strips.