The Twitter sphere has been alive with armyworm alerts this past week. Technology is a powerful tool for sharing information. The problem I have with Twitter is there is no context to the information. It is brief snips of information from a sender that may or may not know what they are talking about to a user that is in the same position.
The positive is that it helps raise awareness of another potential threat to the wheat crop and that part of Twitter is great. Armyworm can be devastating. The negative is the overreaction to a pest that in our experience is very difficult to control. Lots of pictures on Twitter of people finding armyworm. My reaction is good for you, but it doesn't mean anything other than the sender knows how to take a picture of an armyworm. This is the context that is missing in Twitter. The problem appears to be everywhere and that in itself is misleading. Call me an old fart.
It takes low tech boots on the ground and some knowledge to evaluate the actual potential threat. The presence of a few worms does not make the control effort worthwhile. In 19" of row you need to find at least 5 small armyworm.
Why are they hard to control?
1. Armyworm feed at night. During the day they are on the ground at the base of the wheat plant. Spraying should be done late in the evening or at night to get enough insecticide onto the worm to kill him. Spraying during the heat of the day greatly reduces the chances of control. Most spraying, especially by custom applicators is done in the middle of the day. You need to hire a night hawk. My custom applicator, Brian prefers to sleep at night.
2. They armyworm need to be small, less than 1" long. If they are bigger than 1", the chances of control is low. Usually by the time we find them, they are getting too big. Being a worm, they grow very quickly.
3. If you have to search hard to find them, you don't have a problem. That is the situation in most of our area. Just because the neighbour is spraying does not mean you have to spray. A few fields have been sprayed locally and my humble opinion it was a waste of time and money. Re-read my comments on spraying during the day.
4. Insecticides are dangerous to work with. Brian has all the safety equipment necessary, but he still doesn't like using the stuff unless absolutely necessary. I don't blame him.
5. Beware of days to harvest intervals with insecticide use.
Matador 120E 28 days
Dylox 420LC 21 days
Lannate 20 days
The wheat crop is advancing and theoretically there is still time, but the window is closing. We are producing a food crop and these standards should be followed.
Armyworm have been a serious problem in parts of Ontario this year. Around the St Marys area forget it. Use the sprayer to kill weeds in the corn and soybean crops. Leave the insecticide for the farmers that really have the problem.