Trap counts sent in to the network this week from last week’s moth catches indicate that moth flight increased dramatically. And from tweets on Twitter and emails coming in from participants, even higher numbers are being caught this week in some traps. So we haven’t quite reached peak moth flight yet here in Ontario. The top counties that caught the most moths last week were Lambton (93/trap), Haldimand/Norfolk (88/trap) and Chatham-Kent (63/trap). I’ve summarized the results for the top 9 counties so far this year in a graph below:
What does this mean? We still have more scouting to do. With moth counts still increasing, egg laying is also still on the rise. Hot spot areas like Bothwell will start to be less ideal for the moths to lay eggs, as the corn starts to advance into full tassel/pollen shed. Other counties with high trap counts and younger corn are at risk. Though I suggest everyone scout their corn fields at least once or twice these next few weeks, even if trap counts are not that high. Some of the original sites we found the most eggs in this year had very low trap counts initially. Focus scouting efforts to corn fields that have plants with at least a tassel developing in the whorl of the plant to those fields with the tassel fully emerged but not fully shedding yet. These are the fields that seem to be the most attractive for the moths. And if fields have variable plant heights, we also noticed that there tends to be a higher concentration of eggs on what some tease about as “Baute” height corn. No offense to my family members who are taller than me but those who have seen me know that I am a little vertically challenged. So scout shorter corn in a field first before moving deep in.
Since peak flight has not happened yet, dry bean scouting is not quite necessary yet. Most of the crop is still just starting to flower and develop pods. Ideal management timing is when pod feeding can be easily found, which typically takes place 10 to 20 days after peak flight.