"When the insecticide gave out there were still adults coming in that would colonize the field and growers would have some yield loss," Weisz says.
He offers two suggestions for the growers who want to continue to use this strategy. First, he suggests growers who put their insecticide out with their N should go back and take a look at their wheat fields in the second or third week of April and make sure there are no larvae out in the field.
"If there aren't that's great," Weisz says. "That means it worked and it was an inexpensive and easy way to take care of the problem. But if they do see some larvae then they are probably going to want to make another application."
A second consideration for the grower is to make certain he gets good coverage.
"If you are applying an insecticide you want to spray at high pressure, at high gallonage and with a very fine droplet size for good coverage," Weisz says. "That really is just the opposite of what you want when you are applying N. With the case of N, you want the largest droplets with lower coverage, so you don't get a lot of burn. So if you are trying to do both at the same time, you need to think about whether your wheat is strong enough and vigorous enough that it can take some burn, so you can tank mix your N and an insecticide and apply with a good coverage. But if your wheat is struggling a bit so you want to give it every bit of advantage that you can and minimize your burn, you may want to separate those two applications."