Late-season Pest Considerations in Northwest Minnesota
Well, morning and welcome to the fifth Integrated Pest Management podcast for the twenty nineteen summer season. This is Dave Nicolai, I'm the University of Minnesota Extension Educator in Crops, and I also work as a Coordinator for Ag Professional Programming. This morning we are very pleased to have with us one of my co workers, Angie Peltier, who actually offices out of the Crookston Regional Office in Northwestern Minnesota. And to get the ball rolling, Angie, let's have you talk a little bit about yourself and your background and how you came to be in Crookston, Minnesota.
Angie Peltier:Thanks for having me here today, Dave. I started out, I was born, raised and educated in Wisconsin. I got a degree, my degree is in biology and then plant pathology. So field crops, plant pathology. And my major advisor during graduate school was, the field crops extension plant pathologist.
Angie Peltier:So he worked in corn, soybean, and wheat. And so I got exposed to extension early on. I went into extension down in Illinois in a similar regional position for several years. And when a job opened up in Crookston, I decided to make the leap up there. We had some friends Bemidji and it's pretty neat up in the Northern Red River Valley.
Angie Peltier:It's beautiful. There's a lot of sky and a very diverse group of crops that are grown up there. Every So day is a new challenge and so I really appreciate being part of Extension here and I've been here for two years now.
Dave Nicolai:So Illinois, obviously known for corn and soybeans, tell us a little bit about the commodity crops that you're working with currently in the Crookston and the Red River Valley area.
Angie Peltier:Sure, so although there are diverse crops, know, there's canola, potatoes, sugar beets, tons of small grains, and other crops, tasked with working with corn and soybean. Polk County is one of the largest soybean producing counties in the country just for sheer acreage and production. Corn has moved into the Northern Red River Valley. It's up and into Canada now, trying to figure out just how to serve folks that are growing what's a relatively new crop in the area as well.
Dave Nicolai:Well, it's a big area, but I understand that you've had some help this year in terms of scouts and these folks obviously in a lot of locations are an extension of what we do in terms of keeping the status up to date, so to speak, for us and for the growers in terms of corn, soybean production and IPM. I believe you did have a scout and you want to talk a little bit about how that worked and what kind of a program that you were involved with in terms of integrated pest management?
Angie Peltier:Sure, so I had a young man, he's from Mound Minnesota, his name is Oliver Burlin and he was what was called this year the Next Generation Extension IPM intern. So he was part of this internship program and he got exposed to multiple things this season. So he's been involved in several projects including a small grain survey looking at diseases and pest issues and primarily wheat. Soybean survey, so looking primarily for soybean aphids but also keeping his eyes peeled other newer emerging diseases or pest issues. So he's involved in a couple of corn and soybean fungicide trials, us with planting and maintaining those trials, and then helping to maintain several of the University of Minnesota soybean breeding plots throughout the Northwestern Counties in Minnesota.
Angie Peltier:And then this fall he's going to stay on and help with the European Corn War Survey and maybe some targeted soybean system and toad sample collection. I'm very pleased that this young man, he really has helped out a lot and I'm glad to be able to have him through the fall.
Dave Nicolai:He sounds like an excellent candidate perhaps for either a position in agriculture, whether it's in an industry situation or extension, certainly a good opportunity for training. Maybe we should move on and talk a little bit about the commodity crops and the kind of year that we've had. Of course, it's been challenging across all of Minnesota, but Minnesota's a big state and we've had everything from excessive rainfall, prevent planting in Southwestern Minnesota, Southern Minnesota, Southeastern, but in Northwestern Minnesota it's been a little bit different in terms of your precipitation pattern. You want to briefly talk a little bit about what kind of a growing season it's been for corn and soybean producers in your part of the state?
Angie Peltier:Sure, so parts of Polk County and North we were very dry early on so we were able to get planted in a timely fashion whereas we were hearing all those reports from further south in Minnesota and then throughout the I States. The entire Corn Belt it seemed to be was underwater for some time. So we were dry. Actually ended up on the drought monitor map. You can see that we were abnormally dry there for a while too, so we really needed rain.
Angie Peltier:We've gotten some rain recently so crops have started to look pretty good. But there was a time there, I know it was the same throughout the entire state, where the crops just seemed to be at a standstill because it was so cold, cloudy, cold. And so once the crops were able to get a little bit of heat we were able to close rows and get going.
Dave Nicolai:So what is the month of September looking like in terms of maturity of both corn and soybeans? I mean, it's I know it's difficult obviously to predict the weather here, but in terms of the maturity range of crops that are growing in area, Are we going to beat the frost or hope to in Northwestern Minnesota if things look good?
Angie Peltier:So I would say Polk County and North most likely we'll be able to finish up the season. I'm not sure how many additional days we'll have to do some infield drying when it comes to the corns. I think some folks are probably stocking up on propane to dry the crop. But a little bit south we ended up not getting planted on time. So parts of of Norman and Menomon County and south of that, we were very very wet early on and so people weren't able to plant on time.
Angie Peltier:So I would imagine that that frost would, you know, end the crop throughout some of those counties.
Dave Nicolai:In terms of some of your educational programming emphasis, you want to talk a little bit first, I suppose, about soybeans. Now I know you spent some time in educational programming on soybean cyst nematode, but sometimes we in extension have to change gears depending upon, you know, the cards that are dealt in terms of the pest information that's out there in infestation. Talk to us a little bit about soybeans. First of all, where your emphasis has been and then what things did you experience this last year in terms of soybean production in the area involving integrated pest management?
Angie Peltier:So this year we had a couple of issues that we haven't had in previous years. So one thing I got to learn a lot about this summer was thistle caterpillars. So there's been a pretty high population in some fields. I know that in some fields action thresholds have been reached. So what happens though with these caterpillars, it's the Painted Lady butterfly.
Angie Peltier:So very pretty butterfly that looks great until she comes into your field and lays eggs and she'll lay them on the soybeans. Then the caterpillars actually produce a of a webbing and it wraps the leaf around itself. So it creates a little hidey hole to feed inside of away from predators. And so that curled leaf tissue what happens is it's not contributing as much to yield as non curl, non fed upon leaves. But it's very interesting because thistle caterpillars it seems like the butterflies must lay their eggs in the upper part of the canopy and so it's very, it's really alarming when you see just so many curled leaves and think wow there's probably going to be a lot of injury.
Angie Peltier:But then you look a little bit closer and the treatment threshold is caterpillars present and then more than twenty percent injury caused by, feeding injury caused by the caterpillar. And so we haven't seen that in a lot of the fields if you look closer. Know the lower canopy, the middle of the canopy and then upper canopy all told five percent injury in a lot of instances even though it's very alarming to see these these leaves curled at the top of the plant.
Dave Nicolai:Was some of this injury in terms of viewing it defoliation, holes in leaf, or you maybe describe a little bit what you were looking at?
Angie Peltier:So they sit there and they feed and it seemed to me when I was looking at them they'll feed maybe starting at the edge of the leaf but a lot of times it will be towards the middle. They're just eating leaf tissue away. So taking away that photosynthetic area that we need to fill out our pods. But like I said, a lot of people are alarmed coming up to a field right away just because it looks like wow so many of my plants are infested, which they are. A lot of plants are infested.
Angie Peltier:But if you look closer some of them are no longer feeding during the reproductive growth stages. Like I said we need twenty percent feeding injury to consider an insecticide application.
Dave Nicolai:As the economic threshold. Well that also leads into soybean aphid. So what was the status of soybean aphid in the area this year and were there any fields that developed an economic threshold level?
Angie Peltier:So that was something that Oliver Scout and another Scout further south they working on and going into random soybean fields and looking for soybean aphids. And this year it was next to impossible to find soybean aphids. So it was very boring for the scouts, but really good news when it came to what farmers were encountering. So we did several soybean plot tours up in the Northwestern Counties just last week. And when I would ask farmers what they thought about why they weren't seeing soybean aphids in a couple of different locations.
Angie Peltier:Different farmers said because they feel sorry for us. So I thought that was a pretty funny but still interesting that we just haven't seen soybean aphids this year.
Dave Nicolai:Certainly that's going to be a situation that in some places we're still observing or watching, but we're getting, I think in a lot of cases later in August here in September, so some things might change as well, but it's getting towards the end I think in the season. Any other comments about anything else in soybeans disease wise etcetera that you want to talk about?
Angie Peltier:The one thing that continues to keep me up at night is soybean cyst nematode. I continue to worry that folks in Red River Valley, a lot of people don't seem to be aware that this is something that has moved into the area and could for the foreseeable future, I mean until there's some sort of magic bullet, this is something that's going to significantly limit soybean and dry bean yields in the area. You can see up to 30% yield loss before there are above ground symptoms and a lot of people seem to be waiting for those above ground symptoms to come before trying to figure out why their yields are either stagnant or slowly declining over time. So this is something that I really would hope that people start to really focus on because I know that in some fields, entire sections in Norman County, people aren't able to plant soybeans for the foreseeable future just because population densities of soybean system have gotten so high.
Dave Nicolai:Are there any recommendations that you have as far as sampling for a field timing wise, doing something yet this summer or this fall?
Angie Peltier:So I would say what happened last fall was people might have considered collecting samples for SCN, but then the fall got away from them. They were able to get in and harvest their crops. It was very very wet in the fall so a lot of people were you know when they wanted to be harvesting crops it snowed and so that really complicated manners. And so I would say if you're concerned about the harvest season getting away from you and not being able to collect samples anytime that you can collect a sample is better than not collecting a sample. So we would say the more soil cores from the smaller area the better the estimate will be.
Angie Peltier:These soil samples all it's going to do is give us an estimate of population densities, that's very important because that will help us to determine just what crops we should be planting next and how well we're managing soybean cyst nematode in our fields.
Dave Nicolai:One other important crop that you've indicated that you're working with Angie is corn. Do you want to talk some about what were the challenges in 2019 in corn production and what are you seeing in terms of disease and insects etc?
Angie Peltier:Up in the Northern Red River Valley like I said, Polk County in North we were able to get corn planted in a timely fashion. A little bit south of there though Norman, Menomon County in South got corn planted relatively late and they've gotten multiple larger rain events since then. So there's a lot of standing water in some of the fields. These fields tend to have a high clay content and there isn't that, subsurface tiling that a lot of people have further south. So I think that corn yields aren't going to be so great in that area down there.
Angie Peltier:But one of the things that we've noticed as far as disease is concerned is Goss's blight. So we don't have the humid weather that happens a little bit further south when there's a lot of rain. And so we don't get some of the gray leaf spot. We don't get, northern leaf blight where you need long periods of leaf wetness for disease to occur. But what we do get is Gosses blight.
Angie Peltier:So it's always windy in the Northern Red River Valley. But on July 9, we had, wind gusts higher than 50 miles per hour over by Crookston. And so a little bit more than a week later, we started to see symptoms showing up on corn leaves. So large water soaked lesions with wavy borders, little dark green specks inside of those lesions. And then you looked really closely and looked at it kind of sideways or having the sun's light angling down just right, you could see a shiny bacterial ooze as well.
Angie Peltier:So symptoms weren't found on all corn hybrids in this particular trial. And so, some had no disease while others had almost twenty percent incidence. And so that just goes to show how important hybrid selection is when it comes to disease management.
Dave Nicolai:Well, one of the things that growers ask about, know in the southern part of the state is management with Goss'. Just real briefly here, it is a bacteria. You want to talk real briefly about what are some key management things that growers should keep in mind in terms of dealing with this disease?
Angie Peltier:If those leaves that have been infected and have the lesions don't break down before the next time that a corn crop is planted in the field, that's going to provide inoculum for the next corn crop should we get those high wind events, sandblasting, anything that causes a wound on the plant that really tends to favor Goss's Wilt and Goss's Blight.
Dave Nicolai:In terms of fungicide though, I don't believe that that is probably a management technique, you're correct?
Angie Peltier:No, you're correct. So residue management, controlling grassy weed species that can also be hosts, that's important. Longer periods between corn crops and selecting Gauss's blight tolerant hybrids. Those are the primary means of control because you know as with other bacterial diseases, foliar fungicide isn't going to provide any protection. So that's why proper disease identification is just so important because you know foliar fungicide isn't going to protect against spastic wilt.
Dave Nicolai:I know Doctor. Melvik here on St. Paul campus has done some trials looking at different genetics and hybrids and that's an opportunity too of course when you make your seed selection is to investigate that correct?
Angie Peltier:Correct, right. So most of our seed catalogs, Goss's wilt is going to be one of the columns in the seed catalog and we can go through and most of the time they're rated on a one to nine scale and look for those hybrids that have a good to excellent rating. So that's the best way to set yourself up for success when it comes to Goss's Will to Blight.
Dave Nicolai:Well, as we talked about when we started the program in terms of getting into 2020 here from 2019, what are some things that growers should think about or still yet be able to do in the fields here as we go through the month of, well, what's left of August, you know, and into the month of September into harvest, but in terms of this final stretch to harvest.
Angie Peltier:That folks probably have already started to do this but if you haven't yet might be a good time to stock up on propane because you're probably going to have to dry a crop that might not mature before frost and there won't be a lot of time for that infield drying to take place before the snow flies especially in my neck of the woods. Crop scouting is also so important until we get that crop off of the field. This is particularly true when it comes to corn. So, if your corn crop was struggling at all this year, whether it's because of too much or too little rain, Goss's wilt or another leaf disease that reduce photosynthesis, your crop might be at risk for those stalk rotting pathogens. And so going in pushing stalks trying to see if there's breakage, if there's rotted stocks.
Angie Peltier:It's just so important because nobody likes to harvest down corn.
Dave Nicolai:I guess to end up, let's talk a little bit about 2020. You know, what do you anticipate in terms of challenges from an integrated pest management or an agronomic standpoint for next year particularly in the Crookston area and the surrounding counties?
Angie Peltier:Late planting, a lot of rain and slow accumulation of those heat units led to poor canopy closure or slow canopy closure in a lot of fields. Additionally, crop prices meant that margins are very, very tight. And so some of the proven practices such as using those layered residual herbicides to manage weeds, that was unrealistic for many farms. And so this means that weeds might have grown out of control in some fields. And unfortunately, as you know very well Dave, unfortunately weed seeds produced this year, they'll go into that weed seed bank and will cause us problems for years to come.
Angie Peltier:So I'm very worried about that. There's quite a bit of, now we have some of the pigweeds moving into the area. So we have waterhemp, which has proved so challenging in the southern part of the state. We also have just really out of control ragweed. I think we have some herbicide resistant ragweed in our area.
Angie Peltier:So those are going to cause problems for years to come.
Dave Nicolai:I know one of the challenges we have with giant rag and now ragweed and also with common ragweed in the central and northern part of the state is glyphosate resistance. Concerns about that certainly there is in waterhemp as well. So we have to think about diversifying our herbicide portfolio. We have concerns on some of the other mode of actions, ones that are the PPO and herbicides. But basically you've got to know where things are.
Dave Nicolai:So it goes back to your scout. And in terms of that, but farmers scouting on their own and it's something to drive down the road as you obviously drive a lot. And it's flat enough and a lot of that area is you can see those weeds at that bean level height. And now that we didn't close those rows, getting out there to really scout, I think is important. And some of your coworkers are really honest, Doctor.
Dave Nicolai:Tom Peters, our sugar beet extension specialist I know in the area really talks a lot about the concerns on these weeds as well and sugar beets and other weeds, etc.
Angie Peltier:Right and sugar beet production tends to complicate weed management just because there's so many herbicides that actually will have a very long window of time that needs to pass before you can go in and plant sugar beets. We have fewer options when it comes to herbicides in our area if you produce sugar beets. I know Tom has been very good at helping folks to develop weed management strategies just based on what's possible when it comes to sugar beet production.
Dave Nicolai:Well we look forward, Angie, to seeing you on the meeting circuit so to speak again this year, whether it's private pesticide applicator or other commodity crops, soybean, corn, etc, programs out and about. We cooperate with a lot of the folks out of North Dakota State University on different projects and programs along on Red River Valley. So certainly that's a good opportunity to have that one on one conversation. So with that, we thank you for your ability to come in here today and then visit with us on this podcast version for the Integrated Pest Management Program at the University of Minnesota. I'd like to thank Doctor.
Dave Nicolai:Anthony Hansen for the production of this program as we go forward and wish you a lot of good luck Angie in the 2019 of what's left of it and certainly 2020 and we look forward to hearing from you again.
Angie Peltier:That sounds great. I wish all the producers good luck as we move into this harvest season and I hope that everybody has a safe and bountiful harvest.
