2018 Nebraska Cover Crop Conference - Segment 1 - Nathan Mueller and Justin McMechan
There are many benefits to utilizing cover crops, such as improved soil heath and reduced erosion. It’s the details of how and what to do that can present challenges. The Nebraska Cover Crop Conference provides information to growers who are in a corn/soybean rotation and assist them in understanding the value of cover crops. This segment includes the following presentations: "The Banker Won’t like Wheat, but Your Soil Will - Hear Why" - Nathan Mueller, Nebraska Extension Educator and "Will Cover Crops Be a New Home for Insects?" - Justin McMechan, Nebraska Extension Entomologist
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[00:00:10.120]Most importantly, I'd like to recognize
[00:00:13.090]the agencies that have provided financial support
[00:00:18.380]and intellectual support for today's program content.
[00:00:23.000]And first of all, the Nebraska Soybean Checkoff Board
[00:00:26.740]has come to the plate and provided resources,
[00:00:30.040]and I'd like to recognize Victor Bohuslavsky,
[00:00:32.810]who's director back there.
[00:00:34.940]Victor raised his hand, and I saw Greg Reaving walk in,
[00:00:38.470]and I'm sure there's other directors back in the audience.
[00:00:42.400]Thank you very much for your continued support.
[00:00:45.890]Let's give those folks a nice round of applause.
[00:00:53.180]And then also we have the Lower Platte North Natural
[00:00:55.960]Resources District, which is our NRD
[00:00:59.150]here at this facility as well as,
[00:01:01.150]extends all the way up into northeast Nebraska,
[00:01:05.030]and we'd like to recognize them
[00:01:07.510]for providing some financial support.
[00:01:09.840]Tom Mumford is with us today, way in the back.
[00:01:12.380]Thank you, Tom and thank you to the directors
[00:01:14.310]of the Lower Platte North Natural Resources District.
[00:01:16.860]I see Don Veskerna sitting back there.
[00:01:18.720]So thank you folks, let's give them nice round of applause.
[00:01:26.280]And then the USDA SARE program,
[00:01:28.760]which is managed here in Nebraska
[00:01:31.590]through Nebraska extension by Gary Lesoing.
[00:01:34.730]Gary is an extension educator,
[00:01:36.750]and Gary will share more about their resources and that
[00:01:40.378]when I give him the mic sometime today.
[00:01:43.770]And we'd like to thank them for providing support
[00:01:47.740]for this program as well.
[00:01:49.080]Thank you Gary, and let's give Gary and the SARE program
[00:01:52.530]a nice round of applause, if you would.
[00:02:01.624]Okay, I also want to recognize our advisory committee,
[00:02:07.410]made up of Nathan Mueller,
[00:02:09.730]who's our first speaker here today.
[00:02:11.190]Nathan's an extension educator
[00:02:12.870]in Dodge and Washington counties.
[00:02:15.080]Paul Yasha, I don't know if Paul, I haven't seen Paul yet,
[00:02:17.780]but all of you know Paul Yasha,
[00:02:19.300]and Paul also has a very good ear.
[00:02:23.830]Ask him a question, and Paul usually gives you
[00:02:25.890]some really good advice, and we thank Paul for his input.
[00:02:29.480]Dan Gillespie, a farmer who's on the program today.
[00:02:32.790]Dan, thank you very much.
[00:02:34.400]He's from northeast Nebraska.
[00:02:36.810]Jody Saathoff, Jody's with CHS in Menden, Nebraska,
[00:02:42.070]and a real soil, cover crop quality person,
[00:02:47.580]and we thank him for his input.
[00:02:50.030]Mike McDonough, farmer south of Lincoln, thank you Mike,
[00:02:54.030]and again, appreciate the input from those folks,
[00:02:57.630]so let's give them a nice round of applause, thank you.
[00:03:04.430]So on the right side of your packet
[00:03:07.050]is some of the PowerPoints that will be presented today,
[00:03:12.120]a copy of them, and you can refer to them
[00:03:13.764]as the speakers go through each presentation.
[00:03:19.300]We'll hopefully have time at the end of their time slot
[00:03:22.740]for questions, and if we don't,
[00:03:26.060]we'll defer those to the end of the day,
[00:03:28.220]when we'll ask the speakers to come forward,
[00:03:31.510]and we'll have the opportunity to ask them questions
[00:03:35.360]about their operations, their presentations,
[00:03:38.680]their subject matter expertise, and so forth.
[00:03:41.460]This is a day of learning,
[00:03:43.090]and so please feel free to ask questions,
[00:03:47.640]share comments, share experiences.
[00:03:50.670]I know some of you called me in advance, and said,
[00:03:53.060]"You know, this is what I'm doing,
[00:03:54.400]"and boy, I'd like to share that with the audience."
[00:03:56.860]And that's great.
[00:03:58.240]We want to hear it.
[00:03:59.230]We want to take this information back home.
[00:04:01.970]And most of all, we want to apply good management practices
[00:04:06.100]back to the land areas that we are stewards of.
[00:04:09.670]So with that, I'd like introduce
[00:04:10.920]our first speaker, Nathan Mueller.
[00:04:13.900]As I mentioned, Nathan is an extension educator
[00:04:17.300]in Dodge and Washington counties.
[00:04:19.790]He has a very extensive background in the world of agronomy.
[00:04:26.220]Dr. Mueller has worked in South Dakota, Indiana,
[00:04:29.010]Kansas, and has had a number of unique appointments,
[00:04:33.130]a very diversified background,
[00:04:35.580]and I asked Nathan if he would address this topic,
[00:04:40.320]which many of us feel is a very important topic,
[00:04:42.860]and that is adding a third crop
[00:04:46.270]to the corn-soybean rotation.
[00:04:48.690]And we have marketed and developed an agenda today
[00:04:51.460]that focuses on the corn-soybean rotation.
[00:04:55.900]In a perfect world, it is my opinion and philosophy
[00:04:59.200]that we should bring cattle back to the land,
[00:05:02.010]but I know that's never going to happen
[00:05:03.550]on some of your farms.
[00:05:05.040]The only four-legged creature that will be on that ground
[00:05:09.920]is a deer that runs across it or a coyote.
[00:05:13.190]And so we need to focus on how we can
[00:05:15.680]improve soil qualities, improve soil health,
[00:05:19.040]in a corn-bean rotation, or in something different.
[00:05:22.820]So with that, you're on, Nathan.
[00:05:29.950]Great, thank you Keith.
[00:05:31.900]So I've got, I think, the harder sell this morning.
[00:05:34.830]I've been working with farmers on cover crops
[00:05:36.570]since I moved back home here back in 2014
[00:05:39.410]after being in Kansas, Indiana, and South Dakota,
[00:05:43.660]but I also had the opportunity to work with winter wheat
[00:05:45.360]and growers in other states as well,
[00:05:47.486]and that was something, when I moved back,
[00:05:48.380]there's not a lot of people in, north of here,
[00:05:50.840]growing winter wheat.
[00:05:52.820]So I'm going to bring in some success stories of farmers
[00:05:56.320]in the area that have been doing this
[00:05:57.630]and also a little bit of my experience
[00:05:59.530]and where maybe this fits
[00:06:01.380]within some rotations on some farms,
[00:06:03.390]not necessarily every farm.
[00:06:04.970]And I think everybody has diverse operations.
[00:06:06.980]I grew up on a dairy farm in Dodge and Washington county.
[00:06:09.690]Obviously oats was a big part of,
[00:06:12.140]and alfalfa's a big part of our rotation.
[00:06:15.053]So with that I'll get started, maybe.
[00:06:24.480]Turn that on on the side.
[00:06:25.540]Yes, it is, I got a laser.
[00:06:37.890]Okay, so we'll cover the title, if we haven't covered that.
[00:06:43.420]Actually I was driving the interstate.
[00:06:44.590]I'd been making a lot of trips around the state,
[00:06:46.220]giving presentations, and the underground partner,
[00:06:48.900]I saw that the interstate, on a vehicle I think
[00:06:50.870]was for septic systems, and I was like,
[00:06:53.980]weird correlation, happened to be putting this together,
[00:06:56.570]and underground partner,
[00:06:57.650]we'll talk about how the roots of wheat are really,
[00:07:02.120]why the advantage of this rotation might come into play,
[00:07:04.620]not just what's happening aboveground
[00:07:06.940]just in terms of yield and agronomics, perfect.
[00:07:13.700]There you go, good job.
[00:07:18.540]So I'm going to talk a little bit about where we've been
[00:07:20.020]in terms of production here in this part of the state.
[00:07:23.430]Some data to give your banker in terms of hope,
[00:07:25.750]of why this might be something to consider.
[00:07:28.020]Where wheat works, so you know in this area,
[00:07:31.520]your underground partner will cover the soil health,
[00:07:34.040]some of the benefits long-term that we're seeing
[00:07:36.530]with wheat in the rotation.
[00:07:37.550]And then, just to get people started,
[00:07:39.620]I know there's some growers in my area
[00:07:41.350]I've already encouraged to plant winter wheat this fall,
[00:07:43.310]so we'll see how that goes,
[00:07:45.340]and hopefully everything goes well the first year,
[00:07:47.490]but just some things to get us started or things
[00:07:49.380]to think about when you're going to grow winter wheat.
[00:07:52.660]So where we've been at.
[00:07:53.700]So crop reporting district,
[00:07:55.941]USDA National Ag Statistic Service puts this together.
[00:07:59.370]These are our three crop reporting districts
[00:08:01.100]here in eastern Nebraska.
[00:08:02.900]And so where we've been for acres.
[00:08:04.750]On the top here is southeast Nebraska.
[00:08:06.960]In the green, east central Nebraska.
[00:08:09.160]On the bottom, northeast.
[00:08:10.310]And one thing you're going to notice real quick here,
[00:08:12.590]northeast Nebraska's behaved very differently
[00:08:14.960]in terms of wheat production in the past
[00:08:17.370]than the southern crop reporting districts.
[00:08:20.340]But the just of this, this is acres here
[00:08:21.930]on the vertical axis, years on the bottom,
[00:08:24.420]and we've seen a decrease in overall acres to winter wheat
[00:08:28.438]really since the 1950s,
[00:08:30.540]since they've started keeping records.
[00:08:32.380]You notice the little blips here,
[00:08:33.810]but northeast Nebraska, why was there not production
[00:08:37.830]of winter wheat in northeast Nebraska?
[00:08:45.272]Oats, part of it was winter hardiness too.
[00:08:47.900]So when I was in South Dakota, winter wheat's actually
[00:08:50.240]picked up acres in southeast South Dakota.
[00:08:53.200]Spring wheat acres have gone down.
[00:08:55.350]There's more yield potential of winter wheat,
[00:08:57.260]and now we have varieties that have better winter hardiness
[00:08:59.540]than we used to, thus the change in that area,
[00:09:02.580]so why there might be some potential further north here
[00:09:04.970]for winter wheat than what we had in the past.
[00:09:08.330]So what does this look like spatially?
[00:09:10.290]Back in 1958, most of our acres, again,
[00:09:13.120]east central and southeast Nebraska,
[00:09:15.130]we fast forward to 2016, most of our wheat acres,
[00:09:19.260]here in the southern interior along Kansas,
[00:09:21.470]and then up in Knox County, bordering South Dakota.
[00:09:25.050]Large absence of winter wheat now in east central Nebraska,
[00:09:28.320]compared to what we used to, have seen back in the '50s.
[00:09:33.230]So some success stories and some things
[00:09:35.660]I just want to make you aware of.
[00:09:36.920]I pulled this up this morning.
[00:09:39.470]Many people don't know this, and I had ADM and Schooler
[00:09:42.200]come to my winter wheat program
[00:09:43.480]I had a couple weeks ago in Fremont.
[00:09:45.190]Right now if you hauled winter wheat to Fremont,
[00:09:47.600]you would get $.85 above the futures price,
[00:09:50.300]a positive basis, okay?
[00:09:52.980]That's a big deal.
[00:09:54.450]So we're at $5.60 almost for wheat,
[00:09:57.170]and for new crop, $5.31, so that basis translates.
[00:10:01.420]I had no idea this existed before I moved to Kansas
[00:10:04.570]and South Dakota, even though I grew up
[00:10:06.110]and was born in Fremont.
[00:10:07.760]And the reason was, they said,
[00:10:09.550]"Well, where are you from?"
[00:10:10.720]Instead of saying Hooper, I'd say Fremont,
[00:10:12.130]and they said, "Well, I've hauled wheat there."
[00:10:13.120]I said, "Why would you haul wheat to Fremont?"
[00:10:15.310]And they said, "Well, sometimes the basis is good enough
[00:10:17.080]"we can truck it from Kansas or South Dakota there."
[00:10:22.210]Second thing, where are we at in terms of yields?
[00:10:25.510]Just like corn and soybeans, we've seen genetic gains,
[00:10:27.900]improvements in breeding,
[00:10:29.360]probably not at the same level or pace
[00:10:31.130]we've seen in corn and soybeans,
[00:10:32.460]so that's hurt us a little bit,
[00:10:33.900]but some things are changing.
[00:10:35.380]We had a pretty good clip in increased wheat yields
[00:10:38.440]here in the '50s and '60s,
[00:10:39.960]but it was fairly flat pretty much
[00:10:41.590]from the '70s to the '90s,
[00:10:43.500]but we've seen some increases in winter wheat yield again.
[00:10:46.740]So that's really promising.
[00:10:48.200]And I'm going to even show you some of the yields
[00:10:49.620]that we've been pulling off in the area.
[00:10:51.090]But here, we're almost 70 bushels
[00:10:53.690]for the average for northeast district.
[00:10:56.760]For southeast South Dakota actually,
[00:10:58.300]they were at 70 bushels for a district average last year.
[00:11:02.080]So again, potential for winter wheat yield,
[00:11:05.470]potential especially here in north.
[00:11:08.750]So working with some growers,
[00:11:10.160]one grower that I've been working with
[00:11:11.380]that's been growing winter wheat
[00:11:12.530]in Washington County since early 2000's,
[00:11:16.030]obviously latched onto him as a success story.
[00:11:20.020]And so we convinced to show me, with the variety trials,
[00:11:24.374]with the wheat board, and with Steve Benzinger
[00:11:26.460]to look at adding another variety trial further north.
[00:11:29.140]So this is the first time we had a variety trial
[00:11:31.170]north of the Platte River in 35 years
[00:11:33.580]with the University of Nebraska.
[00:11:35.730]And so what happened year one?
[00:11:37.510]Well, the top-yielding variety from the plot
[00:11:39.640]went almost 140 bushels, okay?
[00:11:43.090]This was with one fungicide application
[00:11:45.500]after soybeans, 100 pounds of nitrogen,
[00:11:48.610]so nothing excessive in terms of inputs either.
[00:11:52.180]But good soils, good left soils,
[00:11:54.120]good high organic matter soils.
[00:11:56.320]So these are the types of yields we've seen,
[00:11:58.990]and that's really a success story.
[00:12:00.710]This was on a good part of the field.
[00:12:02.270]This year, guess what we did.
[00:12:04.139]We put it, the variety trial, counterintuitive,
[00:12:06.100]we put it on the hillside,
[00:12:07.210]which is going to add variability to the plot
[00:12:09.520]but has also made it a little bit more realistic
[00:12:11.976]that guys are going to consider growing winter wheat on.
[00:12:17.090]So 100 bushels.
[00:12:18.460]Another grower that I've talked with several times,
[00:12:21.520]he's added winter wheat into his rotation,
[00:12:23.850]so it's once every five years,
[00:12:26.140]so probably the largest wheat grower in northeast Nebraska.
[00:12:29.230]He's seen over 100 bushel yields the last two years.
[00:12:33.040]His long-term average he said, is probably close to 80.
[00:12:36.100]Same thing in Washington County,
[00:12:38.060]that grower's essentially growing
[00:12:39.930]two winter wheat fields a year.
[00:12:41.960]Why? He has hog manure, he has cattle, okay?
[00:12:46.020]So there's added value to the wheat crop
[00:12:48.200]other than the wheat yield and the wheat price itself.
[00:12:51.640]Jefferson County, a guy that I got wheat seed from
[00:12:54.040]this past year won the yield contest for Nebraska,
[00:12:57.370]and nationally, he was fourth place
[00:12:59.180]in dry land rain fed yields down in Jefferson County
[00:13:02.140]with 119 bushel wheat.
[00:13:04.620]So it can be done.
[00:13:07.420]So how can wheat help?
[00:13:08.970]Manure management flexibility.
[00:13:10.530]If you haven't kept up with the news,
[00:13:11.900]what's happening in Fremont,
[00:13:13.732]we're getting a poultry processing plant,
[00:13:15.510]and manure management flexibility,
[00:13:17.157]growing up on the dairy farm,
[00:13:18.690]that oats field was mostly for that reason.
[00:13:21.880]So if you're going to put up poultry barns,
[00:13:24.260]how are you going to handle the manure?
[00:13:25.430]When is it going to get hauled?
[00:13:26.440]Are you going to have it commercially hauled,
[00:13:28.480]or are you going to buy equipment and do it yourself?
[00:13:30.590]What happens if you have a wet fall,
[00:13:32.100]followed by a wet spring?
[00:13:33.690]What's your backup plan and your manure management plan
[00:13:37.763]to use that manure?
[00:13:38.596]So what happens if you have poorly drained fields
[00:13:40.380]in the Platte River bottom?
[00:13:43.080]Maybe you don't want to drive on those
[00:13:44.410]in the fall and spring any more than you have to,
[00:13:46.440]from a compaction standpoint.
[00:13:47.820]And drier summer months might be worth a lot.
[00:13:50.370]Value of the straw.
[00:13:52.020]One person's considering small, square bales,
[00:13:54.770]and there's a lot of demand in the metro area
[00:13:56.980]for small, square bales that people pay
[00:13:59.090]quite a bit of money for a small, square bale
[00:14:00.650]for decoration, to be honest.
[00:14:02.920]More opportunities for diverse cover crops.
[00:14:05.390]Other speakers will address this today.
[00:14:07.230]Opportunities for cover crops after winter wheat
[00:14:09.590]that we don't have within the corn-soybean rotation.
[00:14:12.550]Potential for getting a nitrogen credit,
[00:14:14.740]a cover crop that's going to help us produce nitrogen.
[00:14:18.530]Corn and soybean yield improvement,
[00:14:19.960]we'll talk about some benefits that we've seen
[00:14:22.010]by adding winter wheat in the rotation,
[00:14:23.410]some other areas of the US.
[00:14:25.490]Opportunities to work with NRCS locally,
[00:14:28.288]in terms of incentive programs and cost share
[00:14:31.450]through EQIP and CSP.
[00:14:34.870]I've just started this time of year.
[00:14:36.360]If you haven't been to pesticide applicator training,
[00:14:38.240]and you come to one of mine,
[00:14:39.490]I'm going to be talking about marestail,
[00:14:40.860]Palmer, and waterhemp.
[00:14:43.000]One way we can deal with that
[00:14:44.300]is growing a winter wheat crop.
[00:14:46.620]Those aren't an issue during the wheat crop.
[00:14:48.800]We'd smother out the marestail,
[00:14:50.461]and then we just don't have the sunlight
[00:14:52.560]for that Palmer and waterhemp to emerge.
[00:14:55.010]So one way to add a crop to manage those besides herbicide.
[00:14:59.110]Soil health and conservation,
[00:15:00.410]we'll talk a little bit about that.
[00:15:03.960]One farmer told me this spring,
[00:15:06.000]with it was a tough spring to get everything planted.
[00:15:08.130]He said it was one less field
[00:15:09.480]that he had to plant to corn this spring.
[00:15:11.720]And that was worth something to him
[00:15:12.990]in terms of a stress load.
[00:15:15.450]And then managing weather risks, we'll talk about that.
[00:15:19.140]So weather extremes, a common thing in Nebraska.
[00:15:22.590]So when do we need moisture?
[00:15:24.050]When's the critical month for corn?
[00:15:27.180]it's our biggest potential for yield loss.
[00:15:28.820]So July, peak water use soybeans,
[00:15:31.330]August, wheat, May, June, during grain fill.
[00:15:36.955]So if we have a dry July and August,
[00:15:39.870]wheat doesn't really care at that point, right?
[00:15:41.610]It's already in the bin, already been harvested.
[00:15:44.010]So again, another way to deal with spatial variability,
[00:15:48.670]temporal variability, and rainfall in the area,
[00:15:50.890]by having a crop that uses water
[00:15:52.450]at a different time of the year.
[00:15:54.900]We can rely on crop insurance, but what happens
[00:15:57.060]if the subsidies for crop insurance go down?
[00:16:00.050]That's already in discussion, right?
[00:16:01.460]It has been, the past few farm bills.
[00:16:03.420]Maybe winter wheat is one way for us
[00:16:05.230]to help mitigate risk besides crop insurance.
[00:16:08.950]Crop water use, winter wheat, 16 to 18 inches,
[00:16:12.760]based on ET in the area, here in eastern Nebraska.
[00:16:15.160]So lower water use than we have with corn and soybeans.
[00:16:18.280]So again, opportunity to grow a cover crop after wheat,
[00:16:21.870]where we know we're going to have some moisture available
[00:16:24.020]to produce some biomass and roots.
[00:16:27.630]So here's some precipitation trends as well.
[00:16:31.000]Here on the vertical axis is inches of rainfall.
[00:16:34.910]Right up top, this is for the months of March, April,
[00:16:37.610]and May, so it's springtime.
[00:16:39.540]What's happening in this area, in east, central Nebraska
[00:16:41.880]in terms of a rainfall pattern, from the 1900s 'til now?
[00:16:48.390]Almost 1.75 inches per century,
[00:16:52.380]in terms of increased rainfall.
[00:16:54.010]So big increase from below eight inches to over nine inches
[00:16:58.230]is the trend that we're seeing.
[00:16:59.360]Obviously Nebraska rainfall, very variable,
[00:17:02.110]but the overall trend, it's getting wetter.
[00:17:04.210]That poses problems with days available to be in the field
[00:17:07.360]to get fieldwork done in the spring for corn and soybeans.
[00:17:10.470]Again, wheat at that point,
[00:17:12.290]you've already planted the past fall.
[00:17:14.520]The nitrogen's already usually on by, in early March.
[00:17:19.520]What's happening during the summer in this area?
[00:17:21.610]June, July, and August, rainfall's essentially flat
[00:17:24.560]to a slight trend of slightly drier.
[00:17:26.997]So wetter springs, continued pattern
[00:17:31.220]of moisture in the summer.
[00:17:32.720]So again, something just to think about.
[00:17:36.940]So wheat, I'm going to talk, switch gears a little bit.
[00:17:40.270]Soil health indicators, okay?
[00:17:42.670]A lot of times, we think about soil health,
[00:17:44.710]and I've been doing this a lot with the Biosolids program
[00:17:46.940]that I help run in Fremont.
[00:17:47.960]Take soil health samples, send it into Midwest Labs,
[00:17:51.010]get 'em back, okay?
[00:17:52.280]That test, one aspect of soil health, CO2 burst,
[00:17:55.910]Haney Test does not test anything
[00:17:57.950]in terms of physical health of your soil at all, right?
[00:18:00.510]So we have biological, physical, the chemical part.
[00:18:05.290]So aggregates, what are aggregates?
[00:18:07.760]Essentially soil aggregating or sticking together, right?
[00:18:11.530]It's that crumbliness or that structure that you see,
[00:18:14.300]and what's aggregate stability?
[00:18:15.760]It's the ability of that soil
[00:18:16.890]to resist falling apart or disintegrating.
[00:18:20.600]Why is that important?
[00:18:22.020]I talked to one of our soil health specialists
[00:18:24.260]here in Nebraska, and he said,
[00:18:25.220]"Aggregate stability is probably the most sensitive
[00:18:27.360]"and the number one indicator of soil physical health
[00:18:30.240]"that I would choose if I had to pick one."
[00:18:34.856]It also measures other things such as
[00:18:35.689]biological indicators as well
[00:18:37.690]because what helps glue that aggregate together?
[00:18:39.870]It is also biological activity, right?
[00:18:43.120]So how can I measure this on my farm?
[00:18:45.270]There's not, I can't send it into a lab,
[00:18:47.650]at least close here, locally, but guess what,
[00:18:49.840]there is an easy way.
[00:18:51.560]There's the wet, water stable aggregates
[00:18:53.680]is the normal way researchers test that.
[00:18:55.500]They essentially run it over sieves and water.
[00:18:57.850]The other way is a slake test,
[00:18:59.410]and it's putting a dry clump of soil
[00:19:01.800]in a column of water and seeing how well it holds together.
[00:19:04.160]It's called a slake test.
[00:19:05.730]So a different way to look at soil physical strength,
[00:19:08.570]but they're highly correlated, okay, so it's a good proxy.
[00:19:13.890]So this is from Dodge and Washington County.
[00:19:16.060]Moody soils, two to 6% slopes.
[00:19:18.870]Different crop rotations, farming practices,
[00:19:20.900]but same place on the landscape, same soils.
[00:19:24.080]We have one here, looks pretty good, and one over here.
[00:19:28.010]So what's going on?
[00:19:29.280]I sent the soil health test in.
[00:19:31.920]This soil right here scored the highest of soil health test
[00:19:34.610]from the lab analysis, okay? 17.6.
[00:19:37.810]This one, 16.
[00:19:40.450]That tested second highest.
[00:19:42.720]But what about soil physical health?
[00:19:44.170]Does that look like a positive thing?
[00:19:46.520]So this is a prairie reference,
[00:19:48.040]which is really hard to find.
[00:19:49.990]I had to use satellite imagery to find a prairie reference
[00:19:52.500]in Dodge and Washington County on moody soils.
[00:19:55.140]This is a long-term rotation with corn, soybean,
[00:19:58.370]and alfalfa, long-term no-till.
[00:20:00.780]This is a long-term rotation just with corn-soybeans.
[00:20:03.850]So I don't have wheat in here, because again,
[00:20:06.050]when I was doing this in 2014, didn't sample wheat field,
[00:20:09.770]but just a perennial crop, four years in that rotation,
[00:20:13.460]versus just corn-soybean.
[00:20:15.060]This one, corn-soybean, but just tilled.
[00:20:18.150]So all of these are no-till, this one's tilled.
[00:20:20.380]Again, soil health.
[00:20:21.710]This field called the producer back
[00:20:23.620]after I'd got permission to sample
[00:20:25.300]and got the soil health score and said,
[00:20:26.680]"Man, that was really high."
[00:20:28.280]He said, "That field does have a history of hog manure."
[00:20:32.063]And that CO2 burst was really high, the microbial activity,
[00:20:34.590]but that again, doesn't measure
[00:20:36.389]all of our soil health parameters or indicators, okay?
[00:20:40.940]And I'm going to use kind of this,
[00:20:43.950]how do roots impact, you know, the aggregate stability,
[00:20:47.220]and we'll talk about how wheat plays a role in that.
[00:20:50.600]So some long-term research.
[00:20:52.140]It's really hard to fund 15-year-long studies
[00:20:55.660]in the current scene within research
[00:20:58.870]in terms of funding cycles, okay?
[00:21:00.730]Generally grants and research money
[00:21:03.120]is in two-year, three-year cycles.
[00:21:05.240]How do I fund a 15-year-long project?
[00:21:07.740]Well, you rob Peter to pay Paul.
[00:21:09.890]You're trying to find money from other projects to float it.
[00:21:13.600]So this study was done in Monmouth in Illinois,
[00:21:16.150]so western Illinois, where they get plenty of rainfall.
[00:21:19.190]Wet soils over top a glacial tilt, really high yields,
[00:21:22.810]and they wanted to know the same thing,
[00:21:24.410]"What happens if we add winter wheat into the rotation?"
[00:21:27.520]So we looked at aggregate stability,
[00:21:30.330]here, just like I mentioned
[00:21:31.440]as that indicator for physical health.
[00:21:33.650]This is continuous corn here in blue.
[00:21:36.120]This is a corn-soybean rotation here in orange,
[00:21:38.750]and this is by adding winter wheat.
[00:21:41.000]So we have a lot more water-stable aggregates
[00:21:43.560]just by adding wheat, even in comparison
[00:21:45.510]to corn and soybeans, a little bit advantage to corn,
[00:21:50.890]but wheat is really the big driver here,
[00:21:53.200]similar to what we saw with alfalfa.
[00:21:55.970]What about yields though, so what?
[00:21:57.640]Aggregate stability's better, physical health,
[00:21:59.780]but does that translate to a yield benefit,
[00:22:02.180]a direct economic benefit?
[00:22:04.070]So over here, we have continuous corn yields.
[00:22:07.940]Then we move up to corn-soybean rotation.
[00:22:10.280]Obviously much higher corn yields here.
[00:22:12.760]At almost close to short of 200,
[00:22:14.940]we add wheat into the rotation,
[00:22:16.380]and they had two different cycles,
[00:22:17.800]putting wheat after soybeans,
[00:22:19.190]versus putting wheat after corn, but again,
[00:22:21.610]if you look at these yields, significant yield increase
[00:22:24.940]with adding wheat to the rotation, in terms of corn,
[00:22:28.570]even where they have lots of moisture, okay?
[00:22:33.610]What about soybeans in that rotation where they added wheat
[00:22:35.990]compared to corn-soybean rotation?
[00:22:37.930]Soybean yields here on the vertical axis,
[00:22:39.750]about 62 bushels per corn-soybean rotation,
[00:22:42.820]the soybean yields.
[00:22:43.780]We add winter wheat, again, 66 to 65,
[00:22:46.700]about a three bushel advantage to soybeans.
[00:22:49.470]And that's been fairly consistent
[00:22:51.910]from some other studies we've looked at.
[00:22:53.370]So advantage to corn,
[00:22:54.550]and advantage to soybeans in that wheat rotation.
[00:22:57.290]This was problem, the challenge
[00:22:58.570]I was dealing with in South Dakota.
[00:22:59.890]People were dropping.
[00:23:00.830]We had two million acres of winter wheat,
[00:23:02.370]and it was dropping when I left.
[00:23:04.610]And people were saying, the question I was always asked,
[00:23:07.380]"Well, what were your yields for corn after wheat?"
[00:23:10.500]"Oh," they'd say, "20 bushels higher than after soybeans."
[00:23:13.490]I said, "That 20 bushels, times the corn price,
[00:23:15.580]"you're putting that back
[00:23:16.960]"on the wheat balance sheet, right?"
[00:23:21.270]Okay, you've got to realize where the money's coming from.
[00:23:23.370]It's just not from that year.
[00:23:24.810]It could be from past things you did.
[00:23:26.650]When you look at your overall budget for crop rotation,
[00:23:29.530]cropping system, you need to move that money
[00:23:31.630]back to where it came from, okay,
[00:23:33.660]and it's coming from wheat, from those yield bumps,
[00:23:36.430]not from the corn and soybean crop itself.
[00:23:39.040]So some management recommendations.
[00:23:40.690]So if we're going to grow wheat here in eastern Nebraska,
[00:23:42.860]what do we need to worry about?
[00:23:44.730]Number one, work with corn and soybeans over time,
[00:23:48.260]you'll never usually get a grounds to say,
[00:23:50.170]but if you had to put, pick one crop to spray a fungicide on
[00:23:53.610]on a regular basis, you're going to get
[00:23:55.790]more of your money back on wheat on a regular basis
[00:23:58.010]in this part of the state than you are in corn and soybeans.
[00:24:00.510]Saw a big benefit to soybeans this last year,
[00:24:03.040]but those are numbers that we've measured
[00:24:05.410]in some research studies
[00:24:06.270]so we know strike rust is becoming an issue
[00:24:08.560]on a regular basis.
[00:24:10.090]And so that's part of where that's at.
[00:24:11.780]Variety selection number two, 16 bushels Overland,
[00:24:15.130]a really highly-planted variety in this part of the state.
[00:24:18.030]We're 16 bushels better with some of the newer varieties.
[00:24:23.330]Wheat's genetics have changed, okay?
[00:24:25.160]We've seen some improvements.
[00:24:26.720]Row spacing, this was done by one of my counterparts
[00:24:30.000]in Kansas, Doug Shoup.
[00:24:31.630]They looked at 15-inch, versus seven-and-a-half-inch,
[00:24:33.810]so I didn't have to buy another piece of equipment.
[00:24:35.540]I already have a 15-inch planter or drill.
[00:24:37.990]16 bushel yield loss going to 15-inch row wheat,
[00:24:41.370]versus seven-and-a-half, so just something to consider on,
[00:24:44.250]on the equipment side.
[00:24:45.290]Planting delays, when it's wet, like it was this past year
[00:24:48.190]in September, October, we were later.
[00:24:50.550]That's going to hurt us, on average.
[00:24:53.290]Nutrient management, an extra 30 pounds.
[00:24:56.700]In terms of protein, it's more than just
[00:24:59.420]the seven bushels there if you're short on wheat.
[00:25:01.080]So there's two things going on.
[00:25:02.610]And then seeding rate.
[00:25:05.240]So some disease management.
[00:25:06.910]That was the number one thing I talked about.
[00:25:08.990]Fusarium head blight or scab,
[00:25:10.740]that affects the head at flowering,
[00:25:13.030]so if it's wet the two weeks before and wet during flowering
[00:25:15.600]that's a risk.
[00:25:16.433]That's where the fungicide's really going to pay,
[00:25:17.970]and you have to switch the type of fungicide you're using
[00:25:19.880]to a triazole, instead of a strobilurin
[00:25:22.335]because you could make things worse.
[00:25:23.740]So what can we do when we have stripe rust?
[00:25:25.550]Variety selection, scouting, fungicides, okay?
[00:25:28.940]It always starts with scouting.
[00:25:31.678]And again, there's a lot of information in that weed guide
[00:25:34.330]that's produced every year, that thick book,
[00:25:36.390]probably one of the most common books that people
[00:25:38.010]come into the Dodge and Washington County office to buy.
[00:25:41.296]It has tons of information.
[00:25:42.300]Variety, I said, was number two, 16 bushel advantage.
[00:25:44.890]Where do I get variety information?
[00:25:46.590]University of Nebraska's doing variety trials
[00:25:48.830]at five locations just in eastern Nebraska.
[00:25:51.590]Colorado also has a nice database
[00:25:53.580]where you can look at data across the region,
[00:25:57.244]so you can look at how is that wheat variety performing
[00:25:59.690]in Kansas and Nebraska or Colorado and Nebraska.
[00:26:03.740]That's available there.
[00:26:04.760]And then I've started a winter wheat page
[00:26:06.470]at croptechcafe/winterwheat for people as a local resource
[00:26:10.720]that I'm updating on a regular time frame
[00:26:12.410]geared towards winter wheat production in eastern Nebraska.
[00:26:15.680]So locations, Washington,
[00:26:17.500]here at the research center near Mead.
[00:26:20.520]Lancaster, Jefferson, and Clay, so we've got five locations
[00:26:24.360]that the university's doing variety trials on.
[00:26:26.410]Typically, there's 30 varieties.
[00:26:28.020]I think this year there's 31, times five reps.
[00:26:31.770]So that's a lot of plots.
[00:26:32.960]So I'm help, doing some of the ratings
[00:26:34.180]of that at the local one.
[00:26:36.050]I'm going to highlight just a few varieties.
[00:26:38.170]There's a lot available.
[00:26:40.180]Wolf, which is one that's been around for a while.
[00:26:42.690]It's been our top performer over the past three years.
[00:26:45.450]It's moved north well.
[00:26:46.380]It is recommended in South Dakota when I was there as well.
[00:26:49.070]Great standability, early disease resistance.
[00:26:52.720]That's a recommended one,
[00:26:53.820]so that's based on yield history in this area.
[00:26:55.560]Promising would mean we only have two years of yield data,
[00:26:58.150]but it looks promising based on
[00:26:59.470]the first two years of yield data.
[00:27:01.120]Zenda's a new release from K State.
[00:27:03.320]One thing about this one is it's got resistance,
[00:27:06.130]or moderate resistance to Fusarium head blight.
[00:27:08.530]There's not a lot of options of newer varieties available.
[00:27:10.990]Overland was our last one.
[00:27:12.210]That's why it was still planted.
[00:27:13.490]It's a replacement for Everest
[00:27:14.850]because Everest fell apart
[00:27:16.821]in terms of the stripe rust strain for change.
[00:27:18.800]And then it's a replacement for Overland,
[00:27:20.710]and it's actually a little bit later-maturing than Everest,
[00:27:23.446]so that's a plus for us,
[00:27:25.020]and it's done really well over the past two years,
[00:27:26.810]so we'll see what this does year three, this year.
[00:27:29.670]An experimental variety that Steve Benzinger is working on
[00:27:32.390]here in the winter wheat breeding program
[00:27:33.830]at the University of Nebraska, 12561.
[00:27:39.360]I've been pressuring a little bit on this
[00:27:41.010]because it's done really well in eastern Nebraska.
[00:27:43.540]It's done okay out further west,
[00:27:45.920]but we don't have a lot of varieties
[00:27:48.040]that have been successful.
[00:27:49.590]I'm really excited that they're going to,
[00:27:51.110]it looks like they're going to push this forward
[00:27:53.320]and release this variety,
[00:27:54.610]so this'll be a newer variety that we'll see.
[00:27:56.640]It will hopefully be available to us in a few years.
[00:28:00.730]Okay, certified seed.
[00:28:02.760]Usually you buy, corn and soybean farmers, this is an issue.
[00:28:05.980]You're buying seed every year.
[00:28:07.450]Same thing for wheat for us.
[00:28:08.920]Just buy certified seed.
[00:28:10.530]Know that what you have, that the variety you're getting
[00:28:12.860]is what you're paying for,
[00:28:14.200]and then you also get some really important things.
[00:28:15.770]What's the germ?
[00:28:16.830]What's the purity?
[00:28:17.730]What's the seed size?
[00:28:18.780]You need to know all three of those things
[00:28:20.260]to get the seeding rate you want.
[00:28:21.890]Because pounds per acre, just to say,
[00:28:23.860]"I'm going to plant 90 pounds of winter wheat every year,"
[00:28:27.090]is not going to get you where you want to be.
[00:28:28.580]Would you be happy if you wanted 28,000
[00:28:30.960]for a corn plant population, ended up with 35,000,
[00:28:33.760]or ended up with 20?
[00:28:35.430]The answer is no, right?
[00:28:36.870]So that's what can happen if we don't have this information.
[00:28:40.000]So I made a calculator that's on my croptechcafe website.
[00:28:42.920]You put in what week you're planting.
[00:28:44.910]It'll adjust the seeding rate
[00:28:46.120]based on delayed planting for eastern Nebraska.
[00:28:48.180]You put in numbers from that seed tag,
[00:28:49.910]and it'll tell you how many pounds you should seed
[00:28:52.600]of that variety this year,
[00:28:54.400]and then you can even put in how many acres,
[00:28:56.450]and it'll tell you how many bags to order.
[00:28:57.310]Because generally, if you're small acres,
[00:28:58.810]you're dealing with bags, okay, on wheat.
[00:29:02.580]Fungicide treated seed, yes.
[00:29:05.900]So get that, and planting depth,
[00:29:08.790]one-and-a-half inches is my default
[00:29:10.690]planting depth for this area.
[00:29:12.410]Generally moisture's not a problem most years,
[00:29:15.010]and that's the place to go
[00:29:15.900]if you're thinking about starting.
[00:29:17.060]So again, if you have questions on this or need this,
[00:29:19.740]I have that available on the website.
[00:29:23.770]Highlighted here, nitrogen, phosphorous, and sulfur
[00:29:26.130]are the big macronutrients we're concerned about
[00:29:28.350]in winter wheat in eastern Nebraska.
[00:29:32.140]I don't have time to cover all this,
[00:29:33.850]but I wanted to cover chloride.
[00:29:35.140]So my PhD, for three-and-a-half years
[00:29:37.780]was on micronutrient research in corn and soybeans.
[00:29:42.750]This is one that my advisor was working on,
[00:29:44.800]did a meta-analysis while I was there
[00:29:46.830]and consolidated all the research
[00:29:48.820]that had been on chloride in Kansas.
[00:29:51.150]So what did he find?
[00:29:52.230]Well, one, here in Nebraska, in eastern Nebraska,
[00:29:54.790]we haven't done chloride research in a long, long time.
[00:29:57.220]We've done chloride research in the panhandle,
[00:29:59.410]but it's a very different world out there.
[00:30:01.470]So in Kansas, pretty much the central and eastern part
[00:30:04.530]of Kansas is where they're seeing a response to chloride,
[00:30:06.840]not out west, so that would tell me,
[00:30:08.680]eastern Nebraska, higher chance.
[00:30:10.430]But an 8% yield increase with just adding
[00:30:13.120]20 pounds of chloride.
[00:30:15.020]And generally, I'm starting to see soil test values
[00:30:17.230]that say, where our potassium's starting to get low enough
[00:30:19.712]where we might need that anyway.
[00:30:22.570]Chloride suppresses a lot of diseases,
[00:30:24.540]and I said diseases was a very important consideration
[00:30:27.060]for growing winter wheat.
[00:30:28.200]We know that chloride helps with plant health.
[00:30:31.790]And again, top dressed.
[00:30:32.880]This can be easily mixed in with your ammonium nitrate,
[00:30:35.100]your dry urea, whatever products
[00:30:37.321]when we top dress here in the spring.
[00:30:40.660]So I took soil samples this past year
[00:30:42.490]of anyone who grew winter wheat
[00:30:43.790]in Dodge and Washington County.
[00:30:44.850]I said I would scout your fields, no cost.
[00:30:48.230]I'd take soil samples for you, help you out.
[00:30:51.000]That's easy when there's only seven guys, okay?
[00:30:53.710]So that offer still stands at least for another year, okay?
[00:31:00.020]So what did I find?
[00:31:02.300]So I took cores down to 24 inches,
[00:31:04.040]tested for nitrate, sulfur, chloride.
[00:31:06.660]If we're in that low soil test value for chloride,
[00:31:08.630]less than four part per million,
[00:31:09.870]based on K State's recommendations,
[00:31:11.350]we need 20 pounds of chloride.
[00:31:13.160]What did I find?
[00:31:13.993]Chloride levels three, two, one, two, three, two, two,
[00:31:17.560]all low, 100% of the sites, okay?
[00:31:20.470]I did chloride research, just soil samples
[00:31:23.480]back in 2012 on my field, and I got a value of zero, okay?
[00:31:27.480]So we know chloride's low.
[00:31:29.340]We know Kansas is showing a response to chloride in wheat.
[00:31:32.250]We just haven't done the research here.
[00:31:33.600]So I think one first thing would be some on-farm research.
[00:31:37.150]I work with a lot of producers
[00:31:38.630]doing research on their own farms with their equpiment.
[00:31:41.780]This would be one that we could easily look at here
[00:31:43.610]in the future to see if we're finding
[00:31:45.000]the same results as Kansas.
[00:31:47.270]And South Dakota actually is recommending chloride as well.
[00:31:51.580]So with that, I've got a couple minutes for questions.
[00:31:53.690]I did that on purpose, I got my timer up here.
[00:31:56.110]There's my contact information.
[00:31:57.620]You also have a set of my slides.
[00:32:00.180]And with that, I'll turn it over to the crowd
[00:32:01.930]for a few questions before we switch to Justin.
[00:32:06.450]I think it's called Parker Leaf Streak?
[00:32:10.130]Bacterial leaf streak?
[00:32:11.858]It only eats wheat.
[00:32:12.810]Yeah, so that is
[00:32:13.643]a bacterial disease in winter wheat.
[00:32:16.027]It was a real problem in South Dakota,
[00:32:19.660]so they've actually started,
[00:32:20.870]in their winter wheat breeding program,
[00:32:22.190]selecting for bacterial leaf streak resistance.
[00:32:24.820]The differences is most of the diseases, stripe rust,
[00:32:27.670]Fusarium head blight, leaf rust, are all fungal diseases.
[00:32:30.170]So that's a bacterial, which they named it appropriately.
[00:32:32.810]The main way we deal with bacterial diseases is, you know,
[00:32:36.220]either crop rotation or variety selection.
[00:32:38.470]And so variety selection is number one on that.
[00:32:40.910]We haven't had as much problems with it down here,
[00:32:43.970]but we do know some of the varieties for ratings,
[00:32:45.800]at least from the South Dakota evaluation.
[00:32:49.555](Keith speaking inaudibly)
[00:32:50.660]It's a different, it's a different pathogen
[00:32:53.410]than the bacterial disease that we're seeing in corn
[00:32:56.030]that's been talked about lately, so different bacteria.
[00:33:03.004](person speaking inaudibly)
[00:33:11.280]No, it's pot ash or potassium chloride.
[00:33:13.890]So everybody usually has access to pot ash,
[00:33:17.540]and so that is about 44% chloride, so it's real easy.
[00:33:20.630]About 44 pounds of pot ash product
[00:33:22.730]gets you that 20 pounds of chloride.
[00:33:24.810]Again, I still think the biggest benefit
[00:33:27.640]to chlorides likely in wheat,
[00:33:28.730]they have done research on sorghum in corn in Kansas.
[00:33:32.200]Results weren't as consistent a benefit,
[00:33:34.180]so mostly grass species being the number one benefit.
[00:33:40.213]I know it's hard to do,
[00:33:41.760]but do you screen your wheat varieties
[00:33:43.630]for barley yellow dwarf?
[00:33:47.070]Yeah so, that would be a good question
[00:33:49.360]for Steven Wogilo, he's the extension plant pathologist.
[00:33:51.770]He does go around to these variety trials every year
[00:33:54.400]and rates the plots for diseases.
[00:33:56.240]So this past year, he rated all the plots for stripe rust.
[00:33:59.810]Two years ago, he did for Fusarium head blight.
[00:34:02.560]In terms of barley yellow dwarf, I think the protocol is
[00:34:06.230]if there's noticeable disease at a site,
[00:34:08.913]that he then does do those ratings.
[00:34:11.070]So the question would be if he's done those in the past.
[00:34:13.120]At least this past year,
[00:34:14.380]I'm not aware that he did those on any of the plots.
[00:34:17.220]And he's talking about a viral disease in wheat
[00:34:19.970]that's transmitted by aphids, so.
[00:34:26.314]Do you see any,
[00:34:29.330]and maybe you haven't had enough research,
[00:34:31.570]if you went to a shorter season corn hybrid,
[00:34:34.100]so you can get your wheat planted earlier,
[00:34:36.280]do you sacrifice any yield on that?
[00:34:38.560]Yeah, we're actually, Justin's laughing
[00:34:41.450]because we're working on a proposal to look at,
[00:34:44.820]can we alter our maturity of corn and soybeans
[00:34:46.990]to fit three crops in in two years?
[00:34:49.010]Can we do the whole double crop this far north?
[00:34:52.100]Possibly, if we go, exactly what you said,
[00:34:54.190]short season corn.
[00:34:55.900]There's been research done by Roger Elmore and a group
[00:34:58.190]looking at maturity in corn.
[00:34:59.930]They have not seen a huge yield hit with going, I think,
[00:35:03.780]down to 100, 105 at all.
[00:35:06.820]Some questions still on that 90-day region,
[00:35:08.870]but if we can get wheat planted consistently
[00:35:11.190]the last week of September, that could help us out in terms,
[00:35:14.390]maybe even 10 days, in terms of
[00:35:16.310]getting wheat harvested sooner,
[00:35:18.060]versus if we're planting wheat at the end of October.
[00:35:19.960]So it's not a one-to-one correlation on winter wheat,
[00:35:22.850]if you plant a month earlier,
[00:35:23.870]you get a month harvest sooner.
[00:35:26.042]It's probably more of a one-to-three.
[00:35:27.690]So we're looking at that.
[00:35:29.670]The main concern with planting winter wheat
[00:35:31.550]after corn is going to be increased problems
[00:35:33.780]with Fusarium head blight
[00:35:35.220]because that pathogen does affect both corn and wheat.
[00:35:39.970]So Fusarium head blight resistance
[00:35:41.510]like that Zenda would be critical.
[00:35:43.740]Okay, we're done with questions.
[00:35:46.010]So next, I'd like to introduce
[00:35:48.610]our next speaker, Justin McMechan.
[00:35:50.160]He's the Nebraska extension entomologist,
[00:35:52.220]located here at ENREC, so one of our first hires
[00:35:56.210]here at ENREC, with the new model.
[00:35:58.090]He'll be talking about,
[00:35:59.130]will cover crops be a new home for insects?
[00:36:02.730]Great job, Nathan.
[00:36:03.990]Let's give Nathan Mueller a nice round of applause.
[00:36:07.192]Very interesting presentation, thank you Nathan.
[00:36:18.610]All right, good morning everyone.
[00:36:21.530]All right, will cover crops be a new home for insects?
[00:36:28.415](laughing) Yeah, the real question is,
[00:36:31.280]harmful or beneficial to the upcoming or subsequent crop,
[00:36:35.010]that's the question.
[00:36:36.250]And then the subsequent question is to that,
[00:36:38.020]is how can I manage that?
[00:36:39.760]Is there opportunities to manage cover crops
[00:36:42.500]in a way that I could reduce the likelihood
[00:36:44.330]for harmful insects in the system
[00:36:46.410]and increase the likelihood
[00:36:47.590]for some beneficials to carry over?
[00:36:50.500]Well, I've run into the same problem.
[00:36:52.300]Well, no, no, there we go.
[00:36:56.950]No, I got the same issue as Nathan, unable to advance.
[00:37:00.330]I can talk, whole talk, on the title slide.
[00:37:03.252](scattered audience applause)
Yeah, yeah. (laughs)
[00:37:06.960]So there are, we did a literature review, there we go.
[00:37:11.610]I did a literature review on this
[00:37:13.110]and found roughly 39 publications
[00:37:15.560]that are pertinent to the Nebraska system,
[00:37:17.950]and that's really pushing the limits on those systems,
[00:37:20.790]and I've got a bunch of publications listed up here
[00:37:23.740]that either have a beneficial aspect
[00:37:26.380]that they found on the cover crop
[00:37:27.950]or a negative pest potential from that cover crop,
[00:37:31.730]and you can see there's predators and seed feeders.
[00:37:34.080]We're going to hit a couple studies.
[00:37:35.730]And then some of these that I'm going to discuss
[00:37:37.760]are just based on the biology of that particular insect.
[00:37:40.690]Its ecology in the landscape,
[00:37:41.980]the likelihood it would be drawn into a cover crop
[00:37:44.790]and then subsequently, it could be a problem
[00:37:46.780]for the cash crop.
[00:37:48.400]So beneficial insects in cover crops,
[00:37:50.150]vegetation impact on natural enemies alters their mobility.
[00:37:53.610]It's a source of alternative prey.
[00:37:54.940]That's a big one, and you're going to see this
[00:37:56.730]in a study done in Minnesota on soybean aphids,
[00:38:01.240]and its availability in a microclimate
[00:38:02.790]so they can be drawn in to lay eggs
[00:38:04.470]into that particular system.
[00:38:05.920]You could take the exact same slide,
[00:38:07.870]replace this with pest insects,
[00:38:09.580]it'd be the exact same thing.
[00:38:10.910]They want a similar type scenario.
[00:38:12.810]That's why we're discussing both of the systems.
[00:38:15.099]Factors that influence beneficial insects or abundance,
[00:38:17.970]cover crop species is a big one.
[00:38:19.890]We see that especially between broadleaf and grass crops.
[00:38:23.470]Planting and termination timing, termination method,
[00:38:25.710]and environmental conditions.
[00:38:26.750]I list those because some of you may have had,
[00:38:29.650]you know, benefits that you've seen in the system
[00:38:31.100]or problems in the system, but it's buried year to year.
[00:38:33.660]And in part, that's because some of those
[00:38:35.700]environmental conditions are going to be necessary
[00:38:37.730]for it to be a problem.
[00:38:38.870]Slow down the cash crop growing,
[00:38:40.970]and cause a problem that way,
[00:38:42.280]or to lay a termination beyond the point
[00:38:45.090]at which you wanted to.
[00:38:47.010]So we're going to start with the beneficials.
[00:38:48.820]I really want to cover this because I don't want you
[00:38:51.190]to take away from this that I just need to
[00:38:52.610]add insecticide to my cover crop system.
[00:38:54.850]That's not going to help.
[00:38:56.420]We're going to have pest resurgence issues
[00:38:58.020]if you're knocking out beneficials early,
[00:38:59.820]and there are a lot of beneficials in this system.
[00:39:01.840]So I want to briefly cover some of what's been seen.
[00:39:04.760]This is a study from South Dakota
[00:39:06.450]by Lundgren and Fergen in 2010
[00:39:10.060]using slender wheat grass as a perennial system.
[00:39:13.750]They put it in early September.
[00:39:15.200]They terminated it at corn planting.
[00:39:18.040]Here's the pest abundance of Western corn rootworm
[00:39:20.625]by different larval stages, and you can see at third instar,
[00:39:23.330]they actually got a significant reduction
[00:39:24.770]in the number of third instar larvae.
[00:39:26.910]They got somewhat similar emergence,
[00:39:29.230]but it was numerically reduced with a cover crop.
[00:39:32.310]The hand collection showed really two abundant species
[00:39:35.070]that were in this system, some carabid beetles,
[00:39:37.130]and then a staphylinid or a small beetle
[00:39:40.990]that feeds on these particular Western corn rootworms.
[00:39:44.870]So they were abundant in the system.
[00:39:46.650]In fact, the carabid was seven times the number found
[00:39:51.200]in a no cover crop system, and there was 50% greater
[00:39:54.010]of these little staphylinid beetles,
[00:39:55.360]so increased predator abundance and a strong relationship
[00:39:57.990]between the predators that were found in the system
[00:40:00.070]and a reduction in Western corn rootworm,
[00:40:02.150]which is a big issue.
[00:40:03.920]Here's some of the root ratings.
[00:40:05.680]They didn't take yields on this,
[00:40:07.463]which would've been nice to see,
[00:40:08.851]if it corresponded to a significant yield difference,
[00:40:11.200]but these root ratings do show that potential reduction
[00:40:14.220]both years of the study in the amount of root damage,
[00:40:18.060]lower being less damage,
[00:40:20.110]higher being more damage root system.
[00:40:24.210]So ground beetles are kind of, you know,
[00:40:25.930]you can find them in a lot of different papers
[00:40:27.620]in these types of systems.
[00:40:30.020]Another one is planted into soybeans,
[00:40:32.550]and most of these are being approximately two weeks prior
[00:40:36.170]to planting a cash crop, they're being terminated.
[00:40:39.170]Most frequently captured in June and July,
[00:40:41.160]so that kind of gives you an idea
[00:40:42.180]of what pests might be in the system
[00:40:43.680]and will likely be impacted by that.
[00:40:45.640]But there are a diverse set of ground beetles.
[00:40:48.640]We have a study going here,
[00:40:49.830]where we're looking at ground beetles as part of it.
[00:40:52.010]You know, that seed feeder component
[00:40:53.670]and reducing weed seed banks is big.
[00:40:55.970]So not just, you know, attacking potential pests
[00:40:59.760]in the system but also reducing our weed seed banks.
[00:41:03.480]I'm going to hit a couple different studies.
[00:41:05.586]You're going to see this chart
[00:41:06.419]on the top here a lot, or figure.
[00:41:08.480]It's to highlight how the system
[00:41:09.870]was put in for the particular study.
[00:41:12.350]So in the case of this one,
[00:41:13.320]which was done by Koch et al in Minnesota,
[00:41:16.420]they had a range of different crops.
[00:41:17.860]This was an on-farm trial that was done.
[00:41:19.360]They planted right after the corn had matured
[00:41:23.780]and then planted soybeans into this cover crop and mowed it.
[00:41:26.810]So I bring this up because the termination methods
[00:41:29.400]vary so much in these studies,
[00:41:31.050]and lots that you're probably using Roundup to terminate
[00:41:33.900]seems to be the most common thing
[00:41:35.680]from Rodrigo Whirley's survey that he did.
[00:41:38.600]So a mode system, which we should keep note of.
[00:41:42.510]Here's the soybean aphids and predators in the system.
[00:41:45.620]It seems a little backwards, right?
[00:41:47.440]So if you ignored the soybean aphids side
[00:41:49.670]and focused on the predators, you'd say,
[00:41:51.020]"Wow, there's a lot of predators in the without rye!"
[00:41:54.060]That's because they moved to where the soybean aphids were.
[00:41:58.060]So what's really, to focus on is the with rye,
[00:42:00.940]the reduction in soybean aphid populations
[00:42:03.560]in both cases, and they simply moved over
[00:42:06.130]and became abundant in these no rye
[00:42:09.300]or no cover crop situations and started feeding,
[00:42:11.990]but regardless, the soybean aphids were already
[00:42:14.530]building up in high enough number,
[00:42:15.750]they were not able to control them at that point.
[00:42:17.750]So early, seized in control
[00:42:19.650]by a few different predator species,
[00:42:21.230]ladybugs, syrphid flies, and these minute pirate bugs
[00:42:24.320]that you've probably been bit by in the spring and summer.
[00:42:26.430]They're kind of annoying, but they're really good predators
[00:42:28.860]to have in this type of system.
[00:42:31.440]Okay, so we're going to transition from that
[00:42:33.020]into the insect pests because
[00:42:34.060]this is where I get phone calls.
[00:42:35.280]I don't get phone calls saying,
[00:42:36.380]"I have a whole bunch of ladybugs in my field,
[00:42:38.420]"and I'm super-happy," I get phone calls with,
[00:42:40.420]"This happened to my field.
[00:42:41.330]"I want to know what it is and how to control it," right?
[00:42:43.590]So that's what I want to spend some time covering,
[00:42:45.770]I want to provide you with the management
[00:42:47.500]and scouting recommendations for some of these major pests
[00:42:50.730]that could be a problem in a cover crop system.
[00:42:53.160]What they usually are, or the sources for this,
[00:42:55.530]so the host range expands to cover crop and cash crop.
[00:42:58.030]So it started on the cover crop,
[00:42:59.340]and its development was terminated,
[00:43:01.260]it moved onto the cash crop and completed its development
[00:43:04.150]on a cash crop, and the result is damage
[00:43:06.120]to the given cash crop.
[00:43:07.680]It's a suitable overwintering site,
[00:43:09.450]so they're simply going there, laying their eggs.
[00:43:12.120]Or beginning to develop on it,
[00:43:13.730]and then termination of the cover crop
[00:43:15.030]really drives the insect into the cash crop.
[00:43:16.840]Common stalk borer, you know,
[00:43:18.340]it starts in a particular smaller grass.
[00:43:20.640]If the grass is killed off, then it moves off and into corn.
[00:43:25.260]And so here's one of the first ones, black cutworm.
[00:43:27.210]This is not overwinter in our state.
[00:43:29.190]In fact, it comes from the South, comes up every year.
[00:43:31.590]We monitor for it using pheromone traps.
[00:43:34.190]They like dense vegetation in the spring to lay eggs into,
[00:43:37.130]cover crops, right, dense vegetation.
[00:43:39.920]They'll lay their eggs, so they begin to develop.
[00:43:41.870]They're relatively easy to ID, if you need to ID 'em,
[00:43:44.010]they've got these little, black daggers on their back.
[00:43:46.830]But they come up from Texas, and elsewhere in the South.
[00:43:50.080]And lots of the insects that I'm going to talk about
[00:43:52.140]have these degree days associated with them.
[00:43:54.690]So this one has a biofix.
[00:43:55.530]It's where we actually have to catch it in the state
[00:43:57.330]in significant number, and then these numbers,
[00:43:59.538]start counting 'em.
[00:44:00.730]We usually publish this in CropWatch every year.
[00:44:03.460]It tells you, when we get to round 300 or so,
[00:44:06.590]that you could start seeing significant damage,
[00:44:09.440]and when to scout.
[00:44:10.500]So that's an ideal situation if you know you're,
[00:44:13.122]could possibly have problems with this,
[00:44:15.670]we provide this for you for the state.
[00:44:19.110]Leaf damage varies depending on where you're at,
[00:44:21.080]so if you head out at about 90 to 300 or so
[00:44:24.081]degree days past the point of the biofix,
[00:44:26.740]you'll see these little holes in the leaves,
[00:44:28.830]and you can find the larvae there.
[00:44:30.110]That's an indication that they're present
[00:44:31.940]and that you could be walking into something like this
[00:44:33.828]where we start to see significant cutting.
[00:44:36.810]If you got three to 5% cut, you may want to treat.
[00:44:39.972]BTs do control these, bip 3a, cry1F,
[00:44:42.590]but if they get too big, they can actually cut right through
[00:44:44.670]that particular BT protein,
[00:44:46.710]and so you can run into problems with black cutworm,
[00:44:49.400]even though you may have a BT product out there.
[00:44:52.460]If you've seen this before, you'll know how this ends,
[00:44:54.700]so don't raise your hand and yell out the answer,
[00:44:57.170]but it does vary based on the temperature
[00:44:59.330]following when they start cutting.
[00:45:00.700]So that's an important scenario because we don't know
[00:45:03.032]if it's 80 degrees or it's 60 degrees,
[00:45:05.860]what's the more likely problem scenario for black cutworm.
[00:45:09.870]How many plants?
[00:45:10.703]Who says 80's the worst-case scenario,
[00:45:13.630]raise your hand, a few, yeah.
[00:45:17.580]So in this case, 60's the worst-case scenario,
[00:45:20.390]up to 12 plants because the corn's growing really slowly,
[00:45:23.370]but the black cutworm's growing quite quickly,
[00:45:25.830]and so they can cut up to
[00:45:26.780]12 plants at 60 degrees Fahrenheit,
[00:45:28.900]whereas only 2.3 plants at 80 degrees Fahrenheit,
[00:45:31.610]so look at your forecast for the likelihood
[00:45:33.160]for potential losses from that particular insect.
[00:45:36.310]Nathan provided me this photo,
[00:45:38.520]and this is actually, it was an oat cover crop
[00:45:40.950]planted in the fall.
[00:45:42.502]Oats, of course, died, but there was some seed,
[00:45:43.750]as well as some weeds, and it just shows you
[00:45:45.330]if there's dense vegetation, it could be attracted
[00:45:47.510]to lay eggs and to begin to develop in that system,
[00:45:50.210]and you could clearly,
[00:45:51.760]like if this was a little bit further out in this field,
[00:45:53.150]Nathan said there's a really good standout here,
[00:45:54.490]but you can see cut plants within this particular system.
[00:45:57.090]This is just from last year.
[00:45:59.050]So it is here, it does get into the state every year.
[00:46:03.840]True armyworm's another one.
[00:46:05.310]I'm kind of building up towards a paper
[00:46:06.970]that's focused on a few of these
[00:46:07.880]so you can see some hard numbers.
[00:46:09.510]This one, again from the South comes up,
[00:46:11.612]much like black cutworm,
[00:46:13.130]lays its eggs in early spring vegetation.
[00:46:16.340]They're deposited on lower leaves.
[00:46:18.490]But its damage is quite a bit different.
[00:46:19.920]That's why I show it.
[00:46:20.870]It doesn't really cut plants.
[00:46:22.210]It takes away a lot of the foliage on the plants.
[00:46:25.390]They feed at night, and the majority of the consumption
[00:46:27.780]occurs during the sixth instar,
[00:46:29.090]so this is something you might see initial damage,
[00:46:30.920]but then as you get to the later instars,
[00:46:32.740]it can be quite problematic.
[00:46:34.300]Control with these, you know, it's difficult
[00:46:36.000]once they get greater than an inch in size,
[00:46:38.050]and there are a whole number of predators, parasitoids,
[00:46:39.700]and fungi that will be beneficials in these systems,
[00:46:43.340]so you know, cover crops is kind of an intriguing area,
[00:46:47.050]depending on where you're located
[00:46:48.290]and what the conditions are like in a given year.
[00:46:50.950]Last one I'll cover for this particular group
[00:46:53.140]is common stalk borer.
[00:46:54.580]This one, unlike the previous two, is native to the area,
[00:46:56.978]overwinters every year in Nebraska.
[00:47:00.340]It lays its eggs in the fall, and then subsequently
[00:47:04.240]begins to develop in the spring and can move in.
[00:47:07.367]And lots of BTs control this particular insect.
[00:47:09.860]I have got a few observations to report,
[00:47:12.480]some issues in corn, where it was kind of
[00:47:14.810]spread throughout the field,
[00:47:16.563]indicating that it might have originated from a cover crop,
[00:47:18.630]but we didn't make it to those to verify that,
[00:47:21.300]but it certainly has potential.
[00:47:23.260]Degree days for this, again, more degree days,
[00:47:25.770]these can be tracked.
[00:47:27.430]Insecticide timing's a really important one.
[00:47:29.230]They're moving out of grasses for this particular one.
[00:47:31.990]And so this is kind of something that we also post.
[00:47:36.040]Scout at the 1,300 to 1,400.
[00:47:37.870]So I'm giving you this, and you have the references,
[00:47:40.010]so you know how to look through your system
[00:47:41.600]and watch CropWatch.
[00:47:42.860]We'll post these as we come up in the season,
[00:47:45.410]and you can follow through with them,
[00:47:47.020]scouting in your field.
[00:47:48.260]So here's a paper that encompassed those last three insects.
[00:47:51.320]So Dunbar did this in 2016.
[00:47:54.160]He terminated 1,421 days prior to planting
[00:47:57.500]using a herbicide, and they sampled weekly
[00:47:59.710]all the way through til V8.
[00:48:02.100]Here's the adult pheromone traps
[00:48:03.500]tracking populations of adults coming in.
[00:48:05.680]Here's a rye cover crop, more on the rye cover crop
[00:48:08.000]than was found in the no rye, so they're attracted,
[00:48:10.510]like I said, to lay eggs in that dense vegetation.
[00:48:13.550]And then, here's the black cutworms,
[00:48:15.750]also increased in number, going into the rye cover crop,
[00:48:19.850]so they were attracted to lay eggs in it.
[00:48:21.720]The real question is the damage,
[00:48:23.350]and true army worm was the one that really only had a bump.
[00:48:26.480]Maybe there's a predator aspect to this.
[00:48:28.180]That's one thing that wasn't measured
[00:48:29.500]and could've kept the populations relatively low
[00:48:32.130]after an initial adult capture.
[00:48:34.610]But here we have increased numbers from the rye cover crop
[00:48:38.903]as we move into the field.
[00:48:40.820]And here's the actual insect captures, 19 over one in 2014
[00:48:45.127]and 77 over five, so obviously there's increased numbers
[00:48:48.800]of true armyworm in that particular system.
[00:48:51.230]Black cutworm didn't transcend
[00:48:52.550]to actual numbers in the field.
[00:48:54.250]So whether it's carabid beetles or other things
[00:48:57.100]that are in the system may have taken them out,
[00:48:59.380]their numbers stayed fairly low.
[00:49:01.280]Common stalk borer was in here, it flipped year to year,
[00:49:03.550]and that's a lot of the publications of this 39 that I saw,
[00:49:07.280]depending on which year you looked at,
[00:49:09.110]the results were different.
[00:49:10.510]And that's got to be,
[00:49:11.940]it's frustrating on my part to tell you how to manage risk,
[00:49:14.240]but it says it varies depending on
[00:49:15.580]the environmental conditions, really warrants a lot of work
[00:49:18.260]being done here so we can better understand that.
[00:49:20.910]This is Adam Varenhorst up at South Dakota took this photo.
[00:49:23.970]That is a true armyworm infestation
[00:49:27.448]as the result of a cover crop being placed in,
[00:49:29.940]so they just level the vegetation right off.
[00:49:32.290]So this is something to watch for.
[00:49:34.160]We don't get really high numbers here,
[00:49:35.690]but we can get 'em in the state.
[00:49:38.860]Moving on to stink bugs,
[00:49:40.810]and we do have Tom Hunt, who's kind of,
[00:49:43.430]Tom Hunt and Bob Wright are our two stink bug specialists
[00:49:48.080]in the state, do a lot of work on stink bugs.
[00:49:51.050]These particular critters like to overwinter
[00:49:53.570]in either wooded areas or grass borders
[00:49:56.450]or cover crops in particular,
[00:49:58.630]and Tom's been noticing increasing numbers in Nebraska.
[00:50:02.020]They have a student that's working on this,
[00:50:03.440]trying to understand.
[00:50:05.171]There's like 22 different stink bug species
[00:50:06.650]that can be found in the system.
[00:50:07.900]There are some prevalent ones that I'll talk about,
[00:50:09.680]like brown stink bug, but potentially being pulled into
[00:50:13.550]these cover crop systems are of increasing concern.
[00:50:17.150]So fields with increased risk, no till,
[00:50:18.930]cover crop planted prior to planting,
[00:50:21.080]or corn following wheat.
[00:50:23.510]And then this is actually a cotton study.
[00:50:26.110]A significantly higher number of stink bugs
[00:50:27.990]from the cover crop had no impact on the cotton yields.
[00:50:31.310]I'm going to go through corn and soybeans
[00:50:32.810]related to stink bugs, the impacts, and when they occur
[00:50:35.500]because that's the two most common systems we have here.
[00:50:39.212]Got another question for you guys.
[00:50:41.110]So here is two different stink bug species.
[00:50:44.250]Are they both pests?
[00:50:47.570]Does anybody know the difference between the two?
[00:50:50.130]They're hard to tell apart, even though I had 'em blown up.
[00:50:53.230]I wish they were that big, not in the field,
[00:50:55.250]but I mean, it would be easy for ID and to find 'em
[00:50:57.200]and scout for 'em.
[00:50:58.033]We wouldn't have to sweep.
[00:50:59.789]It would just be, "One's over there."
[00:51:01.320]But they're actually, one is a beneficial, and one's a pest.
[00:51:04.120]So we want to be careful,
[00:51:05.660]especially when looking at beneficials
[00:51:07.150]in cover crop systems that we don't say,
[00:51:08.610]"Oh, there's a stink bug.
[00:51:10.403]"I know what they do, and I'm just going to spray it."
[00:51:13.120]One is the spined soldier stink bug,
[00:51:15.750]which if you flip 'em over and look at their stylet,
[00:51:18.030]one's got a much broader stylet than the other,
[00:51:20.386]and you could pick apart differences in the antennae.
[00:51:23.170]If you're really worried, send me a photo.
[00:51:24.980]Flip it upside down, I'll tell you what it is
[00:51:27.120]and avoid you from spraying if it's not brown stink bugs.
[00:51:31.080]Here's an example.
[00:51:32.410]Jim McGill provided this with me.
[00:51:33.750]This is a spined soldier stink bug,
[00:51:36.240]and a Japanese beetle,
[00:51:37.470]which we're all becoming very attuned with Japanese beetle,
[00:51:40.620]which also like cover crops, unfortunately.
[00:51:44.030]But, you know, this is a nice video that he sent me,
[00:51:46.890]recorded this past season.
[00:51:50.170]Okay, so what do they do?
[00:51:51.810]They overwinter, they mate in the spring, they lay eggs,
[00:51:54.670]and then they go through this development cycle,
[00:51:56.270]and on corn, from the time it emerges,
[00:51:58.810]all the way through 'til the maturity
[00:52:00.490]or just prior to maturity, right, the R2 stage,
[00:52:02.460]it can cause problems.
[00:52:03.830]So corn's got a long window
[00:52:05.240]of potential damage for brown stink bug.
[00:52:08.040]That's primarily the one we find.
[00:52:09.711]There are red shouldered and others
[00:52:11.720]that you can find in corn.
[00:52:13.340]Here's some of the early season damage.
[00:52:14.930]Kill small plants, it causes excessive tillering,
[00:52:17.950]and I saw an excessive tillering corn plant,
[00:52:19.970]and I wondered.
[00:52:20.803]I was going to find out whose photo that was
[00:52:22.870]if that might have been the cause of that.
[00:52:25.090]But you get this shot hole appearance,
[00:52:27.010]where they actually go through all the leaves
[00:52:28.350]when they feed, and it leaves a shot hole as they emerge,
[00:52:31.920]but they'll feed right near the base,
[00:52:33.160]so when you're scouting, you've got to look down
[00:52:34.460]at the bottom of the plants too.
[00:52:35.370]Sometimes they'll be sitting down there.
[00:52:37.040]You won't necessarily see them immediately.
[00:52:40.650]Threshold for this, 5% damage, and they're still present,
[00:52:44.610]and greater than 10% infested,
[00:52:46.296]and the corn is less than two feet tall.
[00:52:48.180]That's for the early part of the season
[00:52:50.240]for recommended thresholds.
[00:52:51.450]These guys like to drop off, too.
[00:52:53.100]So as you're walking up, looking for 'em,
[00:52:54.500]sometimes they just fall right off the plant,
[00:52:56.620]and so they can, they tend to hide,
[00:52:59.340]depending on how you look for 'em.
[00:53:00.560]Late season, aborted kernels, banana ears, you know,
[00:53:03.370]you're looking at just, while the ear's forming,
[00:53:05.620]really V15, V16 as it starts to elongate
[00:53:08.340]and become apparent in the field.
[00:53:10.030]When they feed during that period,
[00:53:11.780]it can really mess up the year.
[00:53:12.900]It causes banana ear appearance
[00:53:14.900]that you see in this image here.
[00:53:16.470]And then later, you know,
[00:53:18.409]they can also cause significant damage,
[00:53:19.242]so there's two different thresholds for those in the system.
[00:53:23.770]Reproductive stage, soybeans, that's really only
[00:53:26.040]when they become a problem is later.
[00:53:28.160]They feed on the pods.
[00:53:29.770]They could cause a stay-green syndrome.
[00:53:32.070]That's really the time, if they're present in the system
[00:53:34.130]while pod forming or pod development, they can cause that.
[00:53:37.750]They also transmitted disease,
[00:53:39.840]and so this is one to watch for
[00:53:41.870]if they're in that particular thing.
[00:53:43.350]5% of plants exhibiting symptoms,
[00:53:45.983]or 10 stink bugs in 25 sweeps,
[00:53:48.290]and green stink bug's one of the big ones.
[00:53:49.890]It doesn't overwinter here.
[00:53:50.930]It comes up from the South every year into the state.
[00:53:54.530]Last one I'll hit on is seed corn maggots.
[00:53:56.830]I got two others, I guess, that are on here,
[00:53:58.590]but seed corn maggot's not a big issue
[00:54:00.300]unless you're killing in your cover crop.
[00:54:01.890]That's kind of what the study found
[00:54:03.470]that I'll cover here briefly.
[00:54:04.930]But if you're, got close proximity to a feed lot,
[00:54:07.480]you got decomposing material,
[00:54:09.250]while they're in flight,
[00:54:10.270]they'll be prone to lay eggs into that particular system,
[00:54:13.690]and they could really hammer a population in a hurry
[00:54:17.870]and knock down a corn population and soybeans as well.
[00:54:20.990]So cold temperatures are a big one on this.
[00:54:23.010]Again, the green days associated with this one
[00:54:25.010]so you can tell when the flights are
[00:54:26.670]so you can avoid pulling them into the system.
[00:54:29.910]This is a study that was run on tillage and herbicides.
[00:54:32.760]It basically shows you that the tillage system
[00:54:34.960]is where you have the greatest number
[00:54:36.360]because of decomposing material
[00:54:38.120]when they're actively moving in the system.
[00:54:40.690]And so it indicates some potential risk from that side.
[00:54:45.150]And then they also found in this one,
[00:54:46.750]there were southern corn rootworms in the system,
[00:54:49.130]or spotted cucumber beetles.
[00:54:50.910]They did cause some significant defoliation.
[00:54:53.050]It came from crimson clover and hairy vetch,
[00:54:55.290]which I haven't really hit too much on,
[00:54:57.530]mostly focusing on grass crops.
[00:54:59.910]But some increased damage there.
[00:55:02.650]Bean leaf beetle's another one.
[00:55:04.050]This was in a clover system, a 1988 study.
[00:55:06.700]They also found Japanese beetle and green clover worm
[00:55:09.640]in that system that were increased, and so some potential.
[00:55:13.160]They like to overwinter in leaf residue,
[00:55:15.438]so they can be brought into the system.
[00:55:17.270]I got a call earlier this spring on wireworms.
[00:55:20.580]They're really highly variable.
[00:55:22.890]They move up and down based on soil temperature,
[00:55:25.440]so if it's cold, they'll be up near the soil surface.
[00:55:27.870]As soon as it gets too warm, they move down.
[00:55:29.800]They get out of the particular root profile area,
[00:55:32.460]and then they're not a problem for the crops.
[00:55:33.860]They're hard to sample, but this was a cover crop
[00:55:37.660]that had been in for three to four years,
[00:55:39.050]and they were seeing some damage.
[00:55:40.780]So it's going to vary year to year.
[00:55:42.010]It's not necessarily a problem in the system.
[00:55:44.270]They're just attracted to CO2,
[00:55:46.520]decomposing material to lay eggs in.
[00:55:48.990]All right, emerging pest issues, cover crops.
[00:55:50.790]I'm going to quickly cover a 2017 issue.
[00:55:53.470]Dan's here, I know we had a 2015 issue
[00:55:55.810]that we'd worked with him on a bit, or Wayne Ono-sourk had.
[00:55:58.960]But you know, these are things that pop up in the system
[00:56:01.060]when you add something to it.
[00:56:02.890]And so this past year,
[00:56:04.320]we got field reports starting on May 23rd,
[00:56:06.720]and it was really across quite a bit of the state.
[00:56:09.610]I hit 11 different fields.
[00:56:11.100]Coulda hit probably 50, 60 fields
[00:56:13.210]and not hit the entire area that was affected by this.
[00:56:17.090]But it came in on May 23rd,
[00:56:18.930]and this is what we were initially seeing.
[00:56:20.260]It almost looked like common stalk borer.
[00:56:22.040]Its dead heart, dying top of a plant,
[00:56:25.200]and some consultants had pulled out the insects,
[00:56:27.200]and they didn't have a head capsule on them,
[00:56:29.427]and so they were saying, "What is this?
[00:56:30.260]"It doesn't look like common stalk borer."
[00:56:32.550]And so we went out and did a large survey on this,
[00:56:35.330]took and scored the plants based on
[00:56:37.310]the symptomology that were in the field
[00:56:39.050]on what we could find.
[00:56:40.800]And as we visited more fields,
[00:56:42.590]we did this relatively quickly from May 30th
[00:56:44.670]through June 5th, and as we got even into the later stuff,
[00:56:48.150]they were already producing tillers.
[00:56:49.330]So the main stem was dying off,
[00:56:51.990]and it was starting to produce a tiller as a result.
[00:56:54.950]We did note some things on the individual plants themselves.
[00:56:58.020]Unlike what Wayne saw in his 2015 information,
[00:57:02.670]we saw them, what appeared to be,
[00:57:04.460]is they came in through the top and bored their way down.
[00:57:06.800]But the channel just continued to increase
[00:57:08.560]as they moved down,
[00:57:09.710]and they would hit the growing point,
[00:57:11.930]and we typically found them within two inches of the bottom
[00:57:14.100]with this channel increase,
[00:57:15.420]and there's actually one sitting right here,
[00:57:16.870]its just really hard to see.
[00:57:18.020]But they're this clear, kind of translucent maggot.
[00:57:22.410]And so here's some of the fields that we sampled.
[00:57:25.550]You know, it varied quite a bit in damage,
[00:57:27.730]but we kind of concentrated our efforts to areas
[00:57:30.270]where we were seeing a large amount of damage.
[00:57:33.100]This is the characteristics of the fields that we sampled.
[00:57:36.140]Wheat or rye, cover crops, planted mid-October
[00:57:39.300]all the way through November,
[00:57:41.049]and then we had corn planting dates that were in April.
[00:57:44.400]And this is the real critical part
[00:57:46.520]that I think is highlighting this issue,
[00:57:48.290]and we're kind of limited in our data set,
[00:57:50.479]but all of these are post-terminations of the cover crop
[00:57:54.710]following corn planting.
[00:57:56.418]And so so many days post-planting.
[00:58:00.060]Here's the range of symptoms that we saw for the fields,
[00:58:02.900]got as high as 50 to 60%.
[00:58:05.110]This particular grower lost about 30 bushels
[00:58:07.640]at the end of the year.
[00:58:09.719]We got a number of different maggots recovered
[00:58:10.980]in a number of different larval sizes.
[00:58:12.290]And the reason we were interested in all that
[00:58:13.520]was we were saying, "Well, what stage were these at?
[00:58:15.470]"Were they consistent across all the fields?
[00:58:17.061]"What kind of conclusions could we draw from that?"
[00:58:19.700]And unfortunately, you know, I got a call from these growers
[00:58:21.960]and they said, "What is this?"
[00:58:23.615]We finally found out what it was,
[00:58:24.448]and the problem was, is that,
[00:58:26.800]we didn't know a lot about the system.
[00:58:28.030]I went back to 1937 to find some biology on this pest.
[00:58:31.570]This is how it matches up in the system.
[00:58:34.080]The adults were present in the spring.
[00:58:35.730]This is when I think they would've infested the crop.
[00:58:38.170]Larval, or eggs were laid.
[00:58:39.570]The larvae began to develop, and then moved
[00:58:41.580]into the subsequent cash crop, causing problems.
[00:58:44.620]We did rear out the adults.
[00:58:45.760]This is what they look like.
[00:58:46.840]They're really quite tiny, but if you sweep,
[00:58:48.580]you should be able to find them in a sweep sample.
[00:58:50.920]All the adults seemed to emerge around the same time.
[00:58:54.220]And this is probably the big take-home message from this
[00:58:56.820]that highlighted cover crops as an issue.
[00:59:00.140]Here's a line defining where a cover crop
[00:59:02.170]was present or absent.
[00:59:03.120]No cover crop within here.
[00:59:04.690]This was an erosion slope that was planted
[00:59:07.430]but didn't get an establishment in that area.
[00:59:09.300]All the area where there was cover crop, there's damage.
[00:59:11.950]It indicates to me it's probably larval movement,
[00:59:14.160]and not adults laying eggs because of how
[00:59:16.560]closely associated it is with the cover crop.
[00:59:19.870]Yield impacts were not clearly defined.
[00:59:21.370]We got two reports of 30 bushel yield losses
[00:59:23.430]on roughly 50% of plants infested.
[00:59:25.620]There's a lot of work to be done on this.
[00:59:26.770]We have a couple studies set up.
[00:59:28.060]We're doing some on-farm studies,
[00:59:29.320]which, if some of you are interested,
[00:59:30.600]I'd be happy to chat with you about doing that.
[00:59:32.950]I'm focused on timing of termination.
[00:59:36.223]Impacts of insects from cover crops depends on
[00:59:37.930]cover crop species, management practices,
[00:59:39.750]environmental factors, not a guarantee
[00:59:41.560]every year in the system.
[00:59:43.640]Scouting to avoid significant losses, that's a big one.
[00:59:45.890]Scout your fields, determine if you really have a problem,
[00:59:48.680]and spraying an insecticide's likely to
[00:59:50.540]eliminate your beneficial insects, so you know,
[00:59:52.650]we don't want to just apply an insecticide.
[00:59:56.460]I did that fast, but I made it, Keith, questions?
[01:00:00.270]Question or two for Justin?
[01:00:06.010]Just a second.
[01:00:15.550]So as far as dormant seeding, would you have,
[01:00:19.060]I assume you'd have less problem with insects overwintering
[01:00:23.180]with the dormant seeding, or is that
[01:00:25.140]going to make much difference with spring flights?
[01:00:27.800]Well, it depends on when it's going to come
[01:00:29.790]into the state, and the amount of biomass that's present.
[01:00:31.970]I'm sure there's a relationship depending on
[01:00:33.630]the amount you have and whether or not
[01:00:35.060]they'll be drawn into that particular system.
[01:00:37.560]But I'm guessing it most certainly
[01:00:39.230]would reduce the fall issues,
[01:00:41.250]so stink bugs and other things that would be
[01:00:42.790]attracted to that in the fall are not going to be
[01:00:45.260]because it wouldn't be present 'til the springtime.
[01:00:48.310]Does that answer your question?
[01:00:53.290]Yeah, up, whichever one.
[01:00:57.810]Wheat stems maggots you got when you were scouting,
[01:01:00.258]and it was all post-termination,
[01:01:03.260]what about pre-termination?
[01:01:05.900]Okay yeah, what about pre-termination, yeah.
[01:01:07.930]So of the fields we sampled, we didn't have any reports.
[01:01:10.820]We had guys who had pre-terminated their field,
[01:01:13.880]but had Roundup issue and had to make a second application.
[01:01:17.040]We actually had one that was never terminated.
[01:01:19.610]So they literally had a wheat crop
[01:01:21.360]in the bottom of their corn crop.
[01:01:23.240]And they had no wheat stem maggot issues.
[01:01:25.640]Even though we found wheat stem maggot in their wheat
[01:01:28.050]because it never left.
[01:01:29.500]It just stayed and completed development on the wheat.
[01:01:32.270]I would, my best guess,
[01:01:33.840]because we're dealing with 80-year-old literature,
[01:01:36.474]and we have a lot to learn on that particular insect,
[01:01:39.012]is that a two-week termination prior to,
[01:01:40.330]and making sure it's good and dead,
[01:01:41.920]I don't imagine those larvae can live long
[01:01:43.930]without a viable host.
[01:01:45.790]They also should desiccate, and it's interesting
[01:01:47.820]how they're getting between plants.
[01:01:49.120]Yeah Justin, on the wheat stem maggots,
[01:01:52.900]first, in 2015, when I first discovered that,
[01:01:57.850]there were two hybrids in the field,
[01:01:59.160]and one was more significantly affected,
[01:02:02.110]and it actually out-yielded the one that was less affected.
[01:02:05.330]But the chart up there,
[01:02:07.059]you studied termination date of the cover crop
[01:02:10.960]relative to planting date of the corn crop.
[01:02:14.260]Tell me again, what was that relationship?
[01:02:17.470]That's the grower's reported information.
[01:02:19.360]We weren't there when that was terminated,
[01:02:20.920]so we're getting information from that grower,
[01:02:22.550]so that's date of Roundup application,
[01:02:24.250]all used Roundup in this particular instance.
[01:02:26.520]And so, you know, you think 11 days
[01:02:28.830]of a death period around that.
[01:02:31.190]That's, the real questions we have,
[01:02:32.800]and what we're tackling this spring
[01:02:33.960]is we're going to track leaf stem maggot
[01:02:36.250]movement of larvae if we can get good populations,
[01:02:39.260]and adult attractedness as it dies from that.
[01:02:42.609]And that was studied
[01:02:44.670]in relationship to termination date.
[01:02:48.840]Correct, Roundup application
[01:02:50.360]relative to the corn planting date, yep.
[01:02:53.010]Yeah, good, thank you for the clarification.
[01:02:55.630]Thank you, Justin.
[01:02:56.500]Let's give him a nice hand.
[01:02:58.850]One of our new and exciting scientists
[01:03:01.940]located here at this facility.
[01:03:05.120]We're excited about the programming
[01:03:06.880]that he'll be generating in the coming year.
[01:03:08.940]So thank you Justin for an important topic.
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