Video 5 - 2020 Virtual Nebraska Soybean Day and Machinery Expo
Considerations for Early-Season Weed Control in Soybeans (PRE-Emergence Herbicides and Cover Crops)
Rodrigo Werle, Assistant Professor & Extension Weed Specialist, University of Wisconsin-Madison
Considerations for Mid-Season Weed Control in Soybeans (Post-Emergence Herbicides and Drift Management)
Rodrigo Werle, Assistant Professor & Extension Weed Specialist, University of Wisconsin-Madison
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[00:00:14.930]So that, we're gonna move on.
[00:00:18.590]Next topic is gonna be weeds.
[00:00:23.300]And there are two faculty members
[00:00:27.120]at the University of Wisconsin
[00:00:29.820]that are going to share with us
[00:00:34.500]their information and experience associated
[00:00:38.070]with the different aspects of weed control.
[00:00:40.750]Now they do have a Nebraska connection
[00:00:45.280]and that Dr. Rodrigo Werle was an extension specialist
[00:00:51.900]for some time at West Central Research and Extension Center
[00:00:55.820]at North Platte.
[00:00:56.830]And Nick Arneson who's a weed science outreach specialist
[00:01:01.740]at UW Wisconsin was in the plant pathology department
[00:01:07.690]on campus here in Nebraska.
[00:01:09.470]So they have a good idea of Nebraska's growing conditions
[00:01:13.800]and challenges associated with weed management
[00:01:17.320]and things like cover crops and all that.
[00:01:19.623]So with that I'm gonna welcome Rodrigo
[00:01:24.627]and Nick and turn it over to them.
[00:01:30.400]Good afternoon everybody,
[00:01:32.340]it's an honor to be here today as weed scientist specialists
[00:01:38.000]in the West Central Research and Extension 2016/2017,
[00:01:42.360]but prior to that, I got my master's and my PhD at UNL.
[00:01:47.300]So it's great to be here today,
[00:01:50.020]I wanna thank you Keith for the opportunity to be here
[00:01:54.688]for everything that you do for agriculture
[00:01:56.970]for being a great mentor to me,
[00:01:59.380]and also to Nick who's gonna be be speaking next.
[00:02:03.157]We are very thankful to you.
[00:02:05.010]You have been a tremendous mentor
[00:02:07.400]in my professional years you have played a big part of it.
[00:02:10.620]So I appreciate the opportunity.
[00:02:12.420]So without further ado,
[00:02:13.845]I think we're probably 10 minutes behind,
[00:02:15.600]as some of you know I like to talk fast,
[00:02:17.750]so let's get this going.
[00:02:19.910]We have three talks scheduled for the next hour here.
[00:02:24.290]I'm gonna give two of them.
[00:02:25.930]First one is gonna be considerations
[00:02:27.610]for early-season weed control.
[00:02:29.500]My next talk is gonna be consideration for mid-season
[00:02:34.100]And then the last talk Nick is gonna give a talk
[00:02:37.210]on considerations for late season weed control.
[00:02:41.067]If you're on Twitter make sure you follow us
[00:02:45.528]@WiscWeeds is our handle on Twitter
[00:02:48.180]and throughout my presentation here
[00:02:49.680]Nick is gonna be sharing some links on the chat
[00:02:52.400]so just so you all have the other resources available.
[00:02:56.140]Okay? Before I start,
[00:02:58.100]I want to acknowledge our sponsors
[00:03:00.610]and also our research team
[00:03:02.870]for the great work that they do
[00:03:05.837]without our sponsors and without this amazing team,
[00:03:08.700]I couldn't be here today presenting to you all.
[00:03:12.850]So as an outline for my first talk
[00:03:14.960]I'm gonna talk about three different series of studies.
[00:03:18.220]The first one looking at cover crops
[00:03:20.490]so cover crop management as a strategy for weed control.
[00:03:24.300]And then we gonna visit crops from our research
[00:03:26.900]and looking at residual control of waterhemp
[00:03:30.020]and giant ragweed.
[00:03:31.810]It is my understanding into the presentation
[00:03:34.870]from artemisiifolia L. Amaranth palmer
[00:03:37.650]has become a major problem in the state of Nebraska
[00:03:41.450]and I'm familiar with that 'cause I've seen
[00:03:43.590]that happening over the years.
[00:03:45.970]But what I wanna say here is that
[00:03:47.450]most of the things that I'm gonna be talking about
[00:03:49.527]for waterhemp also apply to Palmer amaranth.
[00:03:52.000]So hopefully the information I have to provide
[00:03:54.300]I'm gonna be providing here today
[00:03:56.220]is useful for those who are also struggling
[00:03:58.550]with Palmer amaranth.
[00:03:59.890]And then I'm gonna wrap things up talking about
[00:04:02.410]the research conducted by one of our graduate students
[00:04:05.626]looking at some bioassay in the greenhouse
[00:04:08.670]really need data.
[00:04:10.930]So I'm gonna start with this soil management study
[00:04:15.000]that we conducted.
[00:04:16.410]This study is being led by a graduate student Kolby Grint
[00:04:20.976]and Kolby is actually from Nebraska,
[00:04:22.360]he received his bachelor's in agronomy at UNL.
[00:04:25.990]And he's doing his master's degree here with us.
[00:04:28.520]For Kolby's trial we are looking at rotations.
[00:04:31.470]And we're looking how soil management practices
[00:04:34.870]and PRE-emergence herbicides,
[00:04:36.330]in fact, weed control and crop productivity.
[00:04:40.570]In terms of soil management practices
[00:04:42.570]Kolby has evaluated six different practices.
[00:04:45.360]Tillage which is quite popular in Wisconsin,
[00:04:48.380]70% of our acres receive some form of tillage.
[00:04:52.440]We also have a no-till treatment
[00:04:54.580]and then we have four different cover crop
[00:04:58.360]termination strategies here in Wisc Weed.
[00:05:01.354]So the studies I'm gonna be focusing on today
[00:05:03.240]are studies that come from corn
[00:05:05.240]and going to soybeans
[00:05:06.560]this is where I see a lot of promise for cover crops.
[00:05:09.277]Our cover crop treatments are terminated
[00:05:11.430]at four different times and spread if you would.
[00:05:14.240]15 days before planting,
[00:05:17.860]and then 15 days after planting
[00:05:19.990]and termination is usually conducted or done
[00:05:25.970]Before one of our treatments
[00:05:27.260]given that we're in Wisconsin,
[00:05:28.650]there is state we chop the rye before planting.
[00:05:32.818]This are four termination for cereal rye.
[00:05:36.090]So here's just a picture of Kolby's trial.
[00:05:39.230]It's a large trial that we have
[00:05:40.650]and we intend to conduct this trial for multiple years.
[00:05:43.520]We are going into the third rotation here.
[00:05:48.340]So here's a picture of third week May
[00:05:50.330]when we're planting our soybeans.
[00:05:51.417]And this is by far my favorite scenario there.
[00:05:54.240]Here we have a big amount of cover crop biomass
[00:05:56.440]going in green with our soybeans
[00:05:58.730]and then we're terminating here
[00:06:00.500]after planting or a few weeks afterwards,
[00:06:03.170]here's a picture of a treatment
[00:06:05.040]that was terminated in 15 days before planting.
[00:06:08.020]Here's tillage which is quite popular in Wisconsin.
[00:06:11.020]And this is our little tool scenario.
[00:06:12.500]So again, we're looking at weed control
[00:06:14.400]and crop productivity.
[00:06:16.830]The one thing that I wanna point out
[00:06:17.960]and I'm gonna walk through this live rather fast here
[00:06:21.340]is that the best levels of mid-season weed control
[00:06:24.660]were achieved when we had high amount of cover crop biomass
[00:06:29.250]combined with PRE-emergence herbicide.
[00:06:32.270]Okay. So I have a lot of cover crops,
[00:06:34.260]suppressing weeds but PRE-emerge herbicides.
[00:06:37.220]The one challenge that we have in Wisconsin
[00:06:39.370]is that the cereal rye cover crop does not grow very fast.
[00:06:42.790]So if we terminate that at planting,
[00:06:44.560]we have about a 500-700 pounds of dry matter of breaker
[00:06:50.100]whereas if we wait another two weeks
[00:06:51.900]is when we see the big genre.
[00:06:54.110]And remember, if you wanna see good weed suppression
[00:06:56.590]from cover crops,
[00:06:57.670]you wanna let that cover crop grow.
[00:06:59.230]You wanna be terminating
[00:07:00.360]and when is reaching the reproductive stage.
[00:07:03.197]'cause this is when it has
[00:07:04.420]this is the time when the cover crop has
[00:07:06.500]high CN race will take longer to decompose
[00:07:09.500]and it's gonna be doing a good job suppressing weeds.
[00:07:12.740]Okay. So high amount of biomass
[00:07:14.770]combined with the PRE-emergence herbicide program.
[00:07:17.250]This is one when we're seeing outstanding levels
[00:07:19.550]of weed control.
[00:07:21.630]The one question that I get from producers
[00:07:24.320]when I described this scenario here,
[00:07:25.793]this is gonna go back to the speak for here.
[00:07:28.200]When I'm telling the producer,
[00:07:29.320]don't kill this cover crop
[00:07:30.760]no go green planted
[00:07:32.110]and then you spray you pre,
[00:07:33.900]the question that we typically get is
[00:07:35.450]what happens with the pre-emerge herbicides?
[00:07:38.520]Are they gonna stay, hang up during this
[00:07:41.700]all this amount of residue?
[00:07:43.550]So we've done some studies over this past two years.
[00:07:45.790]We have eight side years of data,
[00:07:47.350]and I'm just gonna show
[00:07:48.183]some of our preliminary results here.
[00:07:50.130]So thanks for zone.
[00:07:51.240]While we do 30 days after planting the soybeans
[00:07:54.270]we collect soil cores from zero to three meters in depth
[00:07:58.333]from each one of our plots
[00:08:00.090]and then we submit those samples to South Dakota Ag Labs
[00:08:03.410]and we evaluate the herbicide concentration.
[00:08:06.040]And what we've learned here
[00:08:07.390]over this past couple years is that
[00:08:09.260]usually the tillage treatment
[00:08:10.570]where you have no crop residue
[00:08:12.710]on top of the soil surface
[00:08:15.100]it is where you get the highest amount of herbicide in soil
[00:08:18.270]30 days after application.
[00:08:20.350]However, when we're comparing no till cover crop
[00:08:23.270]early terminated termination
[00:08:25.210]then the late terminated cover crops
[00:08:28.020]those terminated 15 days after planting,
[00:08:31.250]the amount of herbicides in soil 30 days afterwards
[00:08:34.970]was the same.
[00:08:36.060]One thing that I want to point out here is that
[00:08:37.580]this studies are being conducted in Wisconsin,
[00:08:40.000]silt loam soil
[00:08:41.090]and all the times that we conducted this study
[00:08:43.890]within three to four days after the planting,
[00:08:46.310]we received a decent amount of precipitation, you know,
[00:08:49.580]half an ace if not more.
[00:08:51.360]Every time we conducted this study
[00:08:52.950]we had a lot of rainfall in the spring in Wisconsin.
[00:08:55.930]And why is that important?
[00:08:56.763]While as you're spraying PRE-emergence herbicide
[00:08:59.210]in a scenario like this
[00:09:00.780]you wanna make sure you get enough rainfall in there
[00:09:03.660]for that herbicide to get into the soil activated
[00:09:06.600]where it needs to be, okay?
[00:09:08.530]So this is what we actually considered
[00:09:10.470]when looking at this results here.
[00:09:12.820]The next question that I get asked the producers
[00:09:15.490]when we walk through those crops or when I see weeds
[00:09:17.808]it's like as is
[00:09:18.757]what is the impact on use?
[00:09:20.530]I'm not showing four new data here,
[00:09:22.220]I'm gonna focus on soybean yield.
[00:09:24.333]And that's one of the reasons why I really liked the system,
[00:09:26.670]you know planting green
[00:09:27.710]and then terminating afterwards
[00:09:29.840]is because we see no impact,
[00:09:31.890]but at least in our studies in Wisconsin,
[00:09:33.600]we have a summary eight site years of data
[00:09:36.340]out of the eight site years, only one site year
[00:09:38.304]we did see a little bit of a reduction in soybean yield
[00:09:42.770]when the cover crop was late terminated.Okay?
[00:09:45.147]And from both of our studies here
[00:09:46.860]the yield is flat.
[00:09:48.670]So having a cover crop here there is no till
[00:09:50.950]we did not see yield reduct.
[00:09:52.810]So not seeing yield reduction
[00:09:54.740]seen immense levels of weed control
[00:10:00.520]Since we're talking about PRE-emergence herbicide here
[00:10:03.780]I'm gonna switch gears,
[00:10:05.320]and I want to talk about the studies that we've conducted
[00:10:08.030]in 2018, 2019,
[00:10:10.850]and also 2020
[00:10:12.140]at multiple locations here in Wisconsin.
[00:10:15.360]We started this studies to showcase to our producers
[00:10:19.230]the importance of effective
[00:10:21.630]PRE-emergence herbicide programs.
[00:10:24.230]Okay? So here I have data from Lancaster
[00:10:27.310]which where we have a little lower waterhemp pressure
[00:10:30.420]and here I have the data from Brooklyn, Wisconsin,
[00:10:32.613]This is a non-farm research site.
[00:10:35.390]We worked with a group of producers deal Brian brothers
[00:10:38.170]and they have a pretty heavy waterhemp infestation.
[00:10:41.900]The way we look at this data here in blue
[00:10:44.100]we have herbicides with one site of action
[00:10:47.240]from multiple sites of action.
[00:10:48.730]So we have Group 2 herbicides, ALS chemistry.
[00:10:51.870]We have Groups 5, photosystem two,
[00:10:55.279]we have PPO herbicides
[00:10:57.120]and here we have our group 15 herbicides.
[00:10:59.770]In green I have pre-mixes
[00:11:02.270]that contain two sites of action.
[00:11:04.900]And then in red I have pre-mixes that contain
[00:11:07.740]three sites of action.
[00:11:08.880]And I just wanna remind you that
[00:11:10.030]this data is available
[00:11:11.580]and Nick is already sharing in the chat.
[00:11:13.930]So you can download and evaluate this data later on.
[00:11:17.310]But what's my point here?
[00:11:18.600]For waterhemp ALS resistance is widespread,
[00:11:21.870]the same is true for Palmer Amaranth
[00:11:23.420]so when you spray the ALS chemistry by itself
[00:11:25.770]you don't see effective levels of control
[00:11:28.020]like you wanna see, okay?
[00:11:29.400]So this is the dash line
[00:11:30.960]90% control 25 days afterwards.
[00:11:33.410]This is where you wanna be at. Okay?
[00:11:35.600]One herbicide that does quite well
[00:11:37.700]for small seeded weeds
[00:11:39.280]including Palmer and waterhemp is Metribuzin
[00:11:41.870]And that's why Antrobus Metribuzin
[00:11:43.780]has skyrocketed over the past few years.
[00:11:46.900]One thing that I wanna say is
[00:11:48.210]when folks are adopting Metribuzin
[00:11:49.840]you've gotta make sure to use the appropriate rate
[00:11:52.130]even their soils.
[00:11:53.130]Don't cut short under rate,
[00:11:54.780]'cause if you do, you do not see
[00:11:56.620]effective levels of weed control.
[00:11:59.060]Our Group 14 herbicides sulfentrazone
[00:12:02.020]followed by flumioxazin
[00:12:03.910]tend to do a little better job
[00:12:05.070]better job than saflufenacil
[00:12:07.130]or Sharpen by itself.
[00:12:09.670]And then here we have the Group 15s
[00:12:11.976]and all we did in this study with the Group 15s
[00:12:13.710]we did a kind of a full rate and a half rate.
[00:12:16.360]So here I have Warren half rate ,full rate.
[00:12:20.070]Next I have dual half rate,
[00:12:22.300]full rate outlook,
[00:12:24.140]half rate, full rate
[00:12:26.050]and then residual rate full rate.
[00:12:29.000]The level of waterhemp control
[00:12:30.760]varies according to the Group 15 herbicide
[00:12:33.100]And every time we use the reduced rate,
[00:12:35.420]we dropped the levels controlled
[00:12:36.840]trying to convey this matters.
[00:12:38.570]Yeah, you gotta put a PRE-emergence out there
[00:12:40.610]but don't cut on the rates 'cause if you do
[00:12:42.527]you'll see reduced levels of weed control.
[00:12:45.507]The one thing that we learned from the study here is
[00:12:47.340]that every time you combine two active ingredients
[00:12:50.250]that's when you enhance levels of weed control.
[00:12:53.400]For instance, here, I have the combinations
[00:12:55.220]of a Group 14 and a group 2 herbicide
[00:12:59.210]exceeding those herbicides by themselves.
[00:13:02.220]Here I have a herbicide that did quite well,
[00:13:04.120]which is in this case here,
[00:13:05.330]it's 40 Supreme, which is a mixture of so propoxycarbazone
[00:13:09.970]So when you're combining two effective herbicides
[00:13:12.920]by enzymes, you know, as a pre-made series
[00:13:15.200]that enhanced level of control, okay.
[00:13:17.670]So as farmers prepare for weed control at 2021
[00:13:20.000]this is the time to be studying this types of data sets
[00:13:22.850]and select the right PRE-emergence of herbicide program.
[00:13:27.627]Our Rock co farm programs have become very water eccentric.
[00:13:30.394]In the state of Wisconsin giant ragweed is also a problem.
[00:13:33.980]And back then I know giant ragweed
[00:13:36.270]was a problem in Nebraska, little Sandal.
[00:13:38.552]One of my mentors during my time at UNL
[00:13:39.944]did a lot of research.
[00:13:42.046]But one thing that I want to point out
[00:13:44.438]is that giant ragweed in Nebraska
[00:13:45.620]behaves differently than giant ragweed in Wisconsin.
[00:13:48.940]Giant ragweed in Nebraska merge
[00:13:50.560]is earning the season for only like a couple of weeks
[00:13:53.140]for us in Wisconsin It starts germinating in April
[00:13:55.610]and it goes all the way through June July
[00:13:58.508]is when Wisconsin we had this giant ragweed
[00:13:59.990]with an extended emergence window
[00:14:01.650]which makes it very difficult.
[00:14:03.450]So we conducted the same study
[00:14:04.890]for ragweed at a Rock County farm.
[00:14:07.020]And all we've learned here
[00:14:08.210]is a little different than waterhemp.
[00:14:09.800]So as you can see I'm gonna go back
[00:14:11.420]for waterhemp lots of effective options.
[00:14:14.400]Those options are not as effective for giant ragweed.
[00:14:17.150]And that's due to the nature of this weed
[00:14:19.560]with a very large seed size.
[00:14:21.870]Okay. As I said, ALS chemistry is not very effective
[00:14:25.460]pursued classic first rate for waterhemp
[00:14:28.470]because of resistance before giant ragweed
[00:14:30.920]and many other large weed abruptly,
[00:14:33.370]weed seed that we have in our seed bags
[00:14:36.270]ALS chemistry is very effective.
[00:14:37.700]So some of our farms are starting to walk away
[00:14:40.460]from ALS chemistry further PRE-emergence herbicide program,
[00:14:43.560]but then all of a sudden they start missing
[00:14:45.340]because then they start getting more manse orders ,
[00:14:47.400]more ragweeds and some water species
[00:14:49.230]that used to be controlled by this chemistry.
[00:14:51.540]So ALS chemistry (mic drowns out the speaker)
[00:14:53.952]would do the trick for the big weeds
[00:14:55.380]but they're still very helpful
[00:14:57.010]for other weeds that we have in our seed farm.
[00:14:59.370]And that's the one thing I wanna convey here.
[00:15:02.370]So transitioning into the last portion of this first talk,
[00:15:05.460]I wanna talk about the bioessay study
[00:15:07.720]that was conducted by a Victor Ribeiro.
[00:15:10.290]Victor was a masters student
[00:15:12.140]and visiting masters student in our program.
[00:15:14.460]He's here with us on the line today.
[00:15:17.620]So what Victor did,
[00:15:18.810]he went to this site where we did this studies
[00:15:21.460]that I just presented.
[00:15:22.720]And he collected soil samples
[00:15:24.370]at 0,10,20,30,40 and 50 days after treatment.
[00:15:30.050]And he collected soil samples from zero to 10 centimeters
[00:15:33.470]or zero to three inches in depth.
[00:15:35.550]And he brought the samples into the greenhouse
[00:15:37.620]and conducted his bioassay.
[00:15:40.524]As his bio indicator species
[00:15:41.870]we had cereal rye, radish,
[00:15:43.574]Palmer Amaranth, giant Foxtail.
[00:15:47.340]Because of we have limited time here,
[00:15:48.980]I'm gonna to focus on his Palmer Amaranth
[00:15:50.950]and giant foxtail results.
[00:15:53.950]But the intent of this study here was to evaluate over time,
[00:15:57.300]which herbicides did the best job
[00:15:59.890]controlling the weeds that we evaluated
[00:16:01.790]which were Palmer Amaranth and giant foxtail
[00:16:04.740]and also evaluate which herbicides would be least harmful
[00:16:08.780]to our cover crops that then can be seeded
[00:16:11.220]after soybean harvest.
[00:16:13.770]So in terms of results here
[00:16:15.280]the way I went in to look at this figures
[00:16:16.970]one of a bid figure here, but it's very informative.
[00:16:19.490]We have 11 herbicides
[00:16:21.370]from four different sites of action.
[00:16:23.840]Here's the data for Palmer Amaranth,
[00:16:26.080]here's the data for giant foxtail,
[00:16:28.500]data for radish
[00:16:29.930]and then data for cereal rye.
[00:16:32.830]Here what Victor used as an explanatory variable
[00:16:35.670]is accumulated only three days from zero to a thousand,
[00:16:39.280]which is somewhat which represents the zero to 50 days
[00:16:42.680]after treatment. Okay.
[00:16:44.557]And the way he plotted this, he's looking at percent biomass
[00:16:48.220]as compared to the non treated control of the plots
[00:16:50.610]that didn't have herbicide.
[00:16:52.110]So when you're talking about Palmer amaranth
[00:16:53.557]and giant foxtail we wanna see herbicides
[00:16:55.950]reducing the biomass of the weed as much as possible
[00:17:00.170]and having a small, slow period.
[00:17:02.930]You don't wanna see the herbicide degrading fast.
[00:17:04.820]You wanna see good weed control over time.
[00:17:07.140]So for Palmer Amaranth
[00:17:08.640]the most effective herbicides here
[00:17:14.050]and sulfentrazone they provided similar results
[00:17:16.720]but group 15 herbicides.
[00:17:18.920]And sulfentrazone Spartan
[00:17:21.760]followed by S-metolachlor
[00:17:23.780]which is dual and full mesotrione
[00:17:26.410]which has Valor.
[00:17:27.570]So this four herbicides were the most effective herbicides
[00:17:30.490]from Victor's bioassay
[00:17:31.937]from a Palmer amaranth control standpoint.
[00:17:34.900]And then metribuzin was the fifth one.
[00:17:37.440]So my recommendation for folks out there
[00:17:39.560]if you're selecting a PRE-emerge and herbicide programs
[00:17:42.140]looking at Palmer amaranth, waterhemp control
[00:17:44.890]make sure you have one of this herbicides
[00:17:46.930]as part of your pre-program
[00:17:48.400]and if possible combined two of them
[00:17:50.700]at adequate field rates. Okay.
[00:17:52.910]So again Flumioxazin Semicarbazone,
[00:18:01.090]The other thing that I wanna point out is
[00:18:02.440]that this Group 15 herbicides,
[00:18:03.950]both of them are zidua and dual
[00:18:05.570]not only they did great work in Palmer amaranth
[00:18:07.660]but they were also very effective on giant foxtail.
[00:18:10.760]So selecting good herbicides,
[00:18:12.180]their understanding of the weed
[00:18:13.760]then pressure that they have in your seedbed
[00:18:15.670]can be very helpful.
[00:18:17.350]So let's take away from the first presentation here
[00:18:19.620]before I run out of time.
[00:18:22.188]Cereal rye can be a promising component
[00:18:25.890]of weed control programs.
[00:18:27.412]It doesn't have to be grown everywhere.
[00:18:28.620]I know time is, you know,
[00:18:30.420]sometimes there's not enough time in the fall
[00:18:32.230]to get everything planted but our growers can be strategic.
[00:18:35.130]If there are some acres where they're struggling
[00:18:37.210]with Palmer, with waterhemp and radish you know
[00:18:40.400]give it some thought.
[00:18:41.830]PRE-emergency herbicide at the foundation
[00:18:43.450]as they start thinking 2021 weed control programs
[00:18:46.820]make sure you have a good PRE-emergence herbicide program.
[00:18:51.000]And then every time you're considering your weed control
[00:18:53.850]make sure you have non-chemical strategies.
[00:18:56.430]And I'm gonna talk a little bit more about that
[00:18:58.730]in my next talk.
[00:19:00.310]Make sure we use integrated weed management strategies.
[00:19:03.390]So we take some of the selection pressure away,
[00:19:05.910]the base, which waterhemp and Palmer amaranth
[00:19:09.050]are involved in resistance is somewhat scary.
[00:19:12.200]So keep that in mind.
[00:19:13.450]So with that I'm gonna stop here.
[00:19:15.680]Keith I'll stop sharing
[00:19:17.210]and then I'll
[00:19:18.996]if there are questions
[00:19:19.829]how we handle this part now Keith.
[00:19:23.030]Yeah. So if you have questions for Rodrigo
[00:19:27.407]please put them in the chat box
[00:19:29.330]and I'll take a look here real quick.
[00:19:35.830]I don't see anything right now regarding
[00:19:39.690]your comments up till now Rodrigo.
[00:19:45.160]Yeah. So folks on the line here if you have a question,
[00:19:47.247]feel free to add into the chat.
[00:19:49.820]Keith do you want me to keep going here?
[00:19:51.930]Yeah. That'd be fine.
[00:19:55.580]So I'm gonna bring my presentation back here.
[00:20:00.210]And I'm gonna switch gears
[00:20:01.470]so we covered early season weed control.
[00:20:03.640]Use of cover crops, termination of cover crops
[00:20:06.805]and the importance of PRE-emergent herbicide programs.
[00:20:09.080]Now I'm gonna switch
[00:20:10.150]and we're gonna talk mid-season
[00:20:11.900]or post-emergence weed control.
[00:20:15.700]For this talk here,
[00:20:16.850]I'm gonna go through again three series of studies.
[00:20:21.070]The data is gonna is, is available in the chat.
[00:20:23.900]Nick is sharing that
[00:20:25.808]it's also available in the resources
[00:20:27.720]that the Ro has put together.
[00:20:29.490]So the first one we're going to talk about
[00:20:31.434]burndown control of waterhemp and giant ragweed,
[00:20:34.762]we're again gonna talk about
[00:20:36.184]a layered residual approach study
[00:20:38.320]that we conducted in this past couple of years.
[00:20:42.050]And I'm gonna wrap things up talking about
[00:20:44.870]tank-mix with PPO-inhibitors.
[00:20:49.120]One thing that I want to see here
[00:20:50.380]I think we're gonna start to see a lot of liberty
[00:20:54.460]being used out there and glyphosate
[00:20:57.950]will glyphosate this one herbicide
[00:20:59.247]and we're not seeing widespread cases of resistance.
[00:21:03.930]There hasn't been official cases of resistance yet
[00:21:07.524]and it's now a common herbicide across the platform.
[00:21:10.760]So the L LGT 27, your enlist soybeans
[00:21:14.590]and your extend flex platform
[00:21:16.960]now allows for post-emergence applications
[00:21:20.510]It tends to be a very effective herbicide of ragweed
[00:21:23.000]but we need to make sure
[00:21:24.710]we take care of the disturbance side
[00:21:26.340]so we don't quickly select for resistance.
[00:21:28.590]So this is how I'm gonna wrap things up.
[00:21:31.750]So this is a study in the burndown studies
[00:21:33.873]that we conduct after we talk to our growers in Wisconsin
[00:21:39.250]the next question is, okay
[00:21:40.500]now we're in season the winter breaking through
[00:21:42.530]in my corn and soybeans,
[00:21:44.040]how do we control them post emergence?
[00:21:46.410]So in order to address that question
[00:21:47.980]we established a series of studies
[00:21:50.670]comparing 20 different herbicides
[00:21:52.960]herbicides that can be used in corn
[00:21:54.890]and soybeans from multiple sites of action.
[00:21:57.780]So you have your Group 2 ,Groups 4, growth regulators
[00:22:01.210]Group 6,9 and 14 and 27.
[00:22:05.690]On the left here I have waterhemp control
[00:22:08.890]14 days after application
[00:22:10.607]and this weeds were three inches
[00:22:12.750]when we sprayed them.
[00:22:13.760]Remember the three inch mark
[00:22:15.140]we don't wanna let those weeds grow to more than that.
[00:22:18.040]And why is this hard to control them?
[00:22:19.757]We've got to spray them small. So that's what we did here.
[00:22:21.580]So on the left is waterhemp
[00:22:23.360]on the right is giant ragweed.
[00:22:25.620]Given this is soybean talk,
[00:22:27.070]I'm gonna focus on the soybean herbicide.
[00:22:28.890]So ALS chemistry because of resistance
[00:22:31.430]in both specie and waterhemp
[00:22:33.887]and giant ragweed we don't get effective controls
[00:22:36.410]in our trials.
[00:22:37.710]Here I wanna talk about the, you know
[00:22:39.520]the three herbicides,
[00:22:40.610]if you would we can now use in soybeans
[00:22:42.970]like Clethodim, 240 colleen
[00:22:48.117]these three herbicides are the most effective herbicides
[00:22:50.506]for control both waterhemp
[00:22:52.380]and giant ragweed in our trials.
[00:22:54.440]These are important tools they are now available
[00:22:56.710]to our soybean producers,
[00:22:58.230]we gotta take good care of them.
[00:23:01.170]And this is the time of the year
[00:23:02.270]when I started getting these questions
[00:23:04.110]from our producers.
[00:23:04.970]They're right now deciding which seeds to plant
[00:23:08.040]and with the seed decision comes a trade decision, right?
[00:23:10.880]Are we gonna go the came early roundup?
[00:23:12.300]Are we gonna go a 2,4-D roundup?
[00:23:14.070]Or are we gonna go Gramoxone roundup?
[00:23:17.010]And then they asked me which one should I go?
[00:23:18.710]Which one is the best?
[00:23:20.360]So instead of telling them what to do
[00:23:22.190]what I asked Ryan to do
[00:23:23.760]Ryan and bird research technologists in our program
[00:23:26.700]I asked me to compile all the data that we have
[00:23:29.400]offered this past growing season.
[00:23:31.010]So here has got all the data for Dicamba.
[00:23:33.953]You know, he sprays them with soybeans
[00:23:37.170]are about the V3 V4 post-emergence
[00:23:39.450]the weeds are the right size.
[00:23:40.890]So we do everything by the book in our research route.
[00:23:43.770]Okay. So here's dicamba 240 glyphosate
[00:23:48.290]and here's a tank mix that is allowed in the enlist system
[00:23:51.150]which is a 240 Coleen plus glyphosate.
[00:23:55.280]And as you can see here, 14 days
[00:23:57.080]after application of that control is somewhat equivalent.
[00:24:00.130]Okay? With this thing makes your leading
[00:24:02.580]to a little higher control
[00:24:04.030]but across the board if you can spray
[00:24:05.880]according to the best management practices
[00:24:08.570]for each one of those herbicides
[00:24:09.700]you can get excellent levels weed control.
[00:24:12.410]What Ryan did he started applying the data a little more.
[00:24:15.290]And then he was able to come up with a strategy
[00:24:18.110]where for some of the posts applications
[00:24:19.780]the results weren't as good.
[00:24:21.340]So what he did, he broke down by levels
[00:24:24.150]of PRE-emergence herbicide program.
[00:24:26.400]And he combined levels of post emergence weed control
[00:24:30.450]across the various herbicides.
[00:24:32.440]So here's a scenario in our research trials
[00:24:34.832]where we don't have a PRE-emergence herbicide applied
[00:24:37.387]and this is a very bad idea. Okay?
[00:24:40.120]Getting this under control is very, very challenging
[00:24:42.270]as you most know, and this is waterhemp, okay?
[00:24:45.300]This is a fair herbicide program
[00:24:46.900]I didn't want to invest a whole lot.
[00:24:48.210]I put a pre it's better than this
[00:24:50.180]but there are a lot of weeds breaking through. Okay?
[00:24:52.900]So fair, a good herbicide program
[00:24:55.270]about 80 to 90% reduction in waterhemp density.
[00:24:59.000]And this is where I want our farmers to be
[00:25:01.047]I want them to be using an excellent herbicide program.Okay?
[00:25:04.610]So as you can see here the waterhemp density
[00:25:06.700]really decreased as you enhance the quality
[00:25:09.820]of your pre-program.
[00:25:11.360]What happens in this scenario,
[00:25:13.430]you have fewer weeds to control post emergence
[00:25:15.930]and then when you have a scenario like this
[00:25:17.960]the levels of post-emergence weed control
[00:25:20.740]14 days after that post application
[00:25:23.330]now towards the end of the season is enhanced. Okay?
[00:25:27.610]So it is important that we start strong
[00:25:29.900]so we can finish strong
[00:25:31.380]and we can help this technologies last longer
[00:25:34.220]because if we lose them because of resistance
[00:25:36.550]and other factors,
[00:25:38.100]it isn't clear how we're gonna handle
[00:25:39.730]this weeds post emergence. Okay?
[00:25:43.160]So now I wanna switch gears a little bit
[00:25:45.380]and I want to talk about this trial here
[00:25:47.290]which is gonna lead me to the next one
[00:25:49.870]because of some of the observations we took
[00:25:52.120]from this study here.
[00:25:53.480]So this is what we're recommending
[00:25:55.420]for farmers dealing with waterhemp and Palmer amaranths.
[00:25:58.780]Layered residual approach, right?
[00:26:00.890]So you put a PRE-emergence at the time of planting,
[00:26:04.050]and then when the weeds are breaking your pre-emerge
[00:26:06.150]herbicide program about three, four to five weeks
[00:26:08.760]into the growing season you come with your post program.
[00:26:11.660]This was an LL GT 27 soybean cultivars
[00:26:14.800]so we used vital liberty as our main post program.
[00:26:20.053]And what we did, we compared that
[00:26:22.278](motor engine roars)
[00:26:23.790]with the addition of Group 15 herbicides
[00:26:26.540]or Magnum, dual ultra Magnum outlook residual, right?
[00:26:30.413]This is a recommendation you spray your Glyphosate
[00:26:33.697]and a Group 15 to retain.
[00:26:35.560]And when we do that we do see an enhanced
[00:26:38.510]level of control when compared to the Glyphosate post only.
[00:26:43.110]But what really got our attention
[00:26:44.600]is when we brought Flexstar
[00:26:47.170]dimethenamid into the tank mix.
[00:26:49.070]So we actually combine
[00:26:50.880]because of our treatment structure here,
[00:26:52.420]we combine the Glyphosate and Flexstar,
[00:26:54.980]and we were really surprised with the level of control
[00:26:57.820]that we obtained.
[00:26:58.880]And here's a similar set of treatments where we have
[00:27:02.089]Glyphosate plus prefix.
[00:27:03.710]Prefix is for metsulfuron plus dual
[00:27:06.800]and here's Blazer ultra,
[00:27:08.080]which is flumethasone of Flexstar plus warrants.
[00:27:11.920]So here we have three sites of action
[00:27:14.169]Glyphosate, flumethasone burning the water habits average.
[00:27:18.310]Remember that flumethasone has soil residual activity
[00:27:21.040]so when you combine them with a group 15
[00:27:22.960]now you have two herbicides in the season
[00:27:25.090]providing a residual weed control.
[00:27:27.830]So we were really surprised about the start here.
[00:27:30.590]We brought agronomist
[00:27:31.530]and they were also surprised.
[00:27:32.720]The next question that we got is
[00:27:34.350]what happens to my soybean
[00:27:35.890]when I start mixing the service sites.
[00:27:38.600]And that's what we did this past year.
[00:27:40.520]In 2020, we intend to replicate this studies in 2021.
[00:27:45.280]This study here was conducted at three sites,
[00:27:48.440]two sites in Wisconsin,
[00:27:49.937]and a site in Western Illinois with Dr. Mark Bernard.
[00:27:54.200]And here are some of the results that we obtained.
[00:27:56.460]So for the first part here
[00:27:58.033]we're gonna talk about waterhemp control.
[00:28:00.160]So we put a pre down
[00:28:02.440]with the pre level of control was 20 to 50%.
[00:28:06.521]14 days after the post application
[00:28:09.490]we tested four different BPOs
[00:28:16.800]and then we compared identical phosphinate.
[00:28:19.010]So phosphinate ,Flexstar and Cobra
[00:28:22.670]provided the equivalent levels of control,
[00:28:24.720]they perform better than cadet and resource.
[00:28:28.560]The one thing that I want to point out is that
[00:28:30.000]when we combine this BPO's with phosphinate
[00:28:33.250]every time the control enhanced
[00:28:36.230]and the control for the tank mix of resources
[00:28:39.480]in liberty and Cobra and liberty
[00:28:42.410]was equivalent to the tank mix of at least one
[00:28:47.200]So when we combined two herbicides
[00:28:48.980]that have activity post emerges with glyphosate there,
[00:28:52.124]that's when we saw enhanced levels of control.
[00:28:56.320]Here's crop injury going from zero to 30
[00:28:59.570]the higher the injury you know,
[00:29:01.812]the higher the number here to higher the injury.
[00:29:05.230]And the one herbicide that caused all of injury
[00:29:07.140]and most of us are familiar with this.
[00:29:09.410]It was Cobra.
[00:29:10.280]So Cobra caused about 30% injury
[00:29:12.760]14 days after the application. Okay.
[00:29:15.580]As compared to the other herbicides.
[00:29:17.920]We then took this blocks to yield.
[00:29:21.630]And the cobra that caused about 30% injury,
[00:29:24.080]did not impact yield. Okay?
[00:29:25.730]So the yield is equivalent to the other treatments.
[00:29:28.990]However, when we combine all this BPO glyphosate
[00:29:32.809]for this Cobra mix for the flexstar mix
[00:29:34.997]and for the cadet mix,
[00:29:36.250]we did see a downward trend.
[00:29:38.170]A reduced yield when we combine the full rate of the PPO
[00:29:42.460]with the glyphosate
[00:29:44.270]however that trend was not observed
[00:29:46.560]for the herbicide resource.
[00:29:48.470]So let me combine resource,
[00:29:50.280]which is a PPO herbicide
[00:29:51.370]glyphosate be enhanced waterhemp control
[00:29:54.170]we did not impact soybean yield.
[00:29:56.560]And the same was true when we compare
[00:29:59.010]the same system instead of tank mixing with the PPO
[00:30:02.150]we tank mix it with 240 Coleen.
[00:30:04.150]And remember that this soybeans
[00:30:05.870]we're in the list soybeans. Okay.
[00:30:08.970]So I'm running a short of time here.
[00:30:11.890]I talked about tank mixing herbicides.
[00:30:14.050]It's a promising strategy to postpone resistance
[00:30:16.560]and enhanced levels of weed control.
[00:30:18.470]We're seeing some promising results.
[00:30:20.170]We're gonna continue to study that
[00:30:23.040]before I wrap things up here,
[00:30:24.310]I just wanna switch gears real quick.
[00:30:26.420]And I wanna talk about dicamba
[00:30:28.797]So dicamba has been re registered
[00:30:30.940]for the next five years.
[00:30:33.270]One of the requirements now is that growers add
[00:30:36.800]a volatility reducing agent to the tank mix.
[00:30:41.290]And the reason why that's required is to reduce
[00:30:44.330]dicamba volatility in applications in soybeans.
[00:30:49.330]Okay? So this is gonna be mandatory now.
[00:30:51.700]I know there are some products
[00:30:53.480]that are coming down the pipeline
[00:30:54.720]or some announcements to be made.
[00:30:56.610]One of the products that we had the chance to work with
[00:30:59.270]is VaporGrip Xtra which is already
[00:31:02.820]part of the formulation of Xtendamax
[00:31:05.790]and fexapan, okay.
[00:31:08.250]And the tape herbicide
[00:31:09.690]already have VaporGrip in them.
[00:31:11.503]What we are learning in our trials
[00:31:13.340]is when you bring an additional VaporGrip
[00:31:15.940]into the spray solution,
[00:31:17.920]that helps reduce volatility.
[00:31:19.830]And we have a bunch of data that's available on that.
[00:31:22.830]How it helps it helps buffer the reduction pH, okay.
[00:31:27.740]And this is one of the main reasons
[00:31:29.110]why we see the reduce volatility
[00:31:31.630]and Nick is gonna be sharing some information
[00:31:33.310]with you all.
[00:31:34.143]So again, this is a requirement moving forward
[00:31:37.010]one of the products,
[00:31:38.470]and I'm not endorsing this product
[00:31:39.560]but this is one product that we tested.
[00:31:42.240]And we did see a significant reduction in volatility.
[00:31:46.900]So to wrap things up here,
[00:31:48.580]we talk about chemistry a lot
[00:31:50.700]but we need to think outside of the job
[00:31:53.490]our options inside of the job are getting very limited.
[00:31:57.540]Okay? So when I heard
[00:32:00.010]our producers out there to bring more agronomy
[00:32:03.130]into their program, okay?
[00:32:05.200]This is what Nick is gonna talk about next.
[00:32:07.010]We got to stop spreading the weed seed from farm to farm.
[00:32:11.770]This is something I talked about today.
[00:32:12.973]We want to bring competition into our systems, right?
[00:32:16.090]We want to bring what we call darkness.
[00:32:17.810]We want to bring the canopy as much as possible
[00:32:20.750]to minimize the opportunities for weeds to grow and Savage.
[00:32:24.570]Here's a study that we're conducting.
[00:32:27.800]This is the student Nikola Arsenijevik
[00:32:30.229]from our program.
[00:32:31.062]He is looking at management practices of soybeans
[00:32:34.147]and how that impacts canopy development.
[00:32:36.590]And one that has a big impact is rows base.
[00:32:39.610]So that is our mid maze soybeans.
[00:32:41.630]This picture was taken on July 2nd,
[00:32:44.440]30 inch, same sitting range,
[00:32:47.180]15 inch okay?
[00:32:48.270]some cadet soybeans
[00:32:50.030]view from above, view from the bottom
[00:32:52.860]15 inch soybeans
[00:32:54.170]from above, from the bottom.
[00:32:55.930]If you're a big weed plant growing
[00:32:57.660]where are you likely to be more successful?
[00:33:00.010]Right. So think about that.
[00:33:01.910]So here I leave my contact information.
[00:33:04.110]I'm probably running short on time to take questions
[00:33:07.030]Keith will be happy to take them.
[00:33:09.280]Folks can check our work on Twitter @WiscWeeds
[00:33:12.880]or check our blog was WiscWeeds.info.
[00:33:15.520]So Keith, one more time.
[00:33:16.670]Thank you for the opportunity.
[00:33:18.170]Great to be here today.
[00:33:19.450]And also this information that I presented here today
[00:33:22.973]will be helpful for Nebraska producers
[00:33:25.800]as they move into the 2021 growing season.
[00:33:30.560]Thank you, Rodrigo.
[00:33:31.590]I do have a questions seen in the chat box,
[00:33:38.511]based on your experience in Nebraska
[00:33:41.870]and now based on your experience in Wisconsin,
[00:33:45.770]do you see in terms of private and commercial applicators
[00:33:50.680]in terms of weed control,
[00:33:52.750]do you see anything that you wish you
[00:33:57.169]you can get growers in Wisconsin
[00:33:59.600]to adapt the growers in Nebraska are doing
[00:34:03.400]and vice versa?
[00:34:05.520]Yeah. So that's an excellent question Keith.
[00:34:08.010]I think our time in Nebraska,
[00:34:09.690]prepared us and wanna see us big nine
[00:34:12.967]for the research that we do here was nice.
[00:34:16.690]You know, I remember when I was in graduate school
[00:34:20.180]palmer amaranth was a problem of the West, right?
[00:34:22.260]West part of Nebraska
[00:34:24.030]the problem now is still palmer amaranth
[00:34:26.744]according to a survey is the number one weed.
[00:34:28.910]So the weed is moving across the state.
[00:34:30.870]When I was in graduate school at Nebraska
[00:34:33.033]I remember our mentors there,
[00:34:35.510]the Winc Science we were doing lot of research
[00:34:37.510]with waterhemp, they were 2012, 2013.
[00:34:40.570]We went for field days with you
[00:34:41.850]and several other resistance management field dates
[00:34:44.390]with the marketing board,
[00:34:46.180]talking about the value of pre and later residual qualities,
[00:34:51.897]and where we were in 2012
[00:34:54.553]and 2013 in Nebraska
[00:34:55.440]where we were at in, in Wisconsin.
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