This is the sugar beet report, bringing you the latest information from NDSU throughout the sugar beet growing season. Now that peak fly is well behind us, we can assess the root maggot's damage and keep an eye on other insects. To help us out is Mark Boetel, NDSU Extension entomologist. Mark, now that we're well past fly activity, what are they up to now?

So the larvae that either survived or are not exposed to an insecticide application were they've been feeding since early June, so we've got about two months worth of feeding activity that's happened. So that's really, dropping off. And now that those larvae have pretty well finished feeding, they're ready to overwinter, so they're gonna drop away from those roots and then burrow down deep into the soil a little over a foot deep and begin overwintering.

How did this year's populations compare to past years?

The populations were very similar to what we experienced in 2024, which was a vast reduction over the past six or seven years. So, certainly, that is a good thing. One thing I would just put a caveat on that is that we did have some pretty severe hot spots. They were certainly isolated, but that's gonna make it very important for people to pay attention to the next year's forecast when we put that out.

Mark, now that we're further along in the growing season, what are some other pests we need to keep an eye on in the beet fields?

I've received several reports of lygus bug activity, in the Southern Minn and Mindaq coop growing areas. So, certainly, we wanna be watching for that, and I would expect that that may increase over the next few weeks to a month. That's one thing to watch out for. I don't think grasshoppers are gonna be a big problem with all the rain that we've had, and now we have more full canopy beets, but I don't expect grasshoppers because of that rainfall, I don't expect the grasshoppers to likely hit economically treatable levels. I've also received a few reports of armyworms in grain fields, mostly wheat fields. So I would just put the kind of a warning or a watch out there that we should be monitoring neighboring beet fields and really other sensitive crops as well closely the next couple weeks. Army worms are very mobile. That's where they get their name. So when crops like wheat mature or and are drying down or certainly we've got some harvest going on now as well, that will stimulate them to move to more green and, actively growing plants like beans, beets, and sunflower. I sort of alluded to it. When we're at full canopy, the beets can sustain a whole lot more foliar feeding. A lot of these pests, even though they may be apparent or observable in the fields, may not be causing economic loss. So we need to really weigh the sort of the economics of benefit and cost with an insecticide application. And then more importantly, I would say at this time of year is we're getting closer to pre pile, so we need to watch out for preharvest intervals on the insecticide labels. With that in mind, I just wanna put a reminder out that it's always important to read, understand, and follow the pesticide label as it is the law.

Thanks, Mark. Our guest has been Mark Boetel, NDSU Extension entomologist. This is the sugar beet report, bringing you the latest information from NDSU throughout the sugar beet growing season.