Western Bean Cutworm Peak Flights

Peak flight is a bit difficult to pin point this week because there is some data missing from our week 10 trap reports however, we have received some missing data from previous weeks so I can provide information on peak flights for some counties and possible peak flights for others.  Some areas are still experiencing increasing numbers and will likely see peak flight this week.

Counties that have likely experience peak WBC flights

Week 8 July 8 – 14: Niagara

Week 9 July 15- 21: Essex, Lampton, Ottawa and York

Counties that have Possible peak flights (more data needed)

Week 8 July 8 – 14: Hamilton/Wentworth and Leeds & Grenville

Week 9 July 15 – 21: Haldimand/Norfolk, Oxford, Elgin, Perth, Waterloo, Wellington

Counties where trap catches are still increasing or holding steady

Week 10 July 22 -28: Bruce, Chatham-Kent, Grey, Hastings, Huron, Middlesex, Renfrew and Stormont, Dundas & Glengarry.

Similar to last season we are seeing some counties peaking while others are still going strong.  Although it’s not fair to say that all of southern Ontario has experienced peak flight I think we should start seeing the numbers decline by week 11. We’ll have to wait and see what the numbers look like for the northern and eastern counties next week though it does appear that Ottawa and Leeds & Grenville may have seen peak activity already.

What’s happening in the Field? Our scouts are heading out to do damage assessments next week so we’ll have a better idea of what to expect in terms of WBC feeding in the cobs. With peak flights coming so late after tassel emergence this year it will be interesting to see how that relates to the potential for damage in the field.

 Dry Beans. Now that we’re starting to see some areas with peak flights, it’s time to start having a look at the dry bean fields for damage from WBC.  The larvae chew holes in the pod and feed on the seeds. If you are spending 30 min in the field and find no damage or only a few pods with holes in them then there is not likely a heavy infestation; check back again in 10 days.  If you can easily find damage, then an insecticide application may be needed.