Joe, welcome back to the War Against Weeds Podcast. I'm Joe Ikely, extension weed specialist at North Dakota State University. My co host today is Sarah Lancaster at Kansas State University. Sarah, how's it going?
Life is good!
We were just comparing frost notes before you hopped on. Decided to exclude you from that conversation today.
I don't like to think about winter,
so that was maybe an ellusion to the guest today. So we've got two guests and one topic to talk about. So we will be discussing the weed Wild Oat. And before we get into that, we should introduce both of our guests. And so first we'll start north of our border and go with Breanne Tidemann. Welcome back to the podcast.
Thanks for having me back.
So for those who maybe didn't listen in before or have short term memory like me, why don't you introduce the what, where you're at, what you do, and why we're having you on to talk about wild oats.
Sure, I'm a weed scientist with Agriculture and AgriFood Canada, based in Lacombe, Alberta. So if you're familiar with the map of Alberta, where Calgary and Edmonton are, I'm pretty much smack dab in the middle. And why I'm here talking about Wild Oat is, it's one of our most problematic weeds up here in the prairies. It's well it and kochia like to duke it out for for number one issue, but this year, we're hearing a whole lot more about Wild Oat again after a few kochia years. So
yeah. And then our other guest is another NDSU person, and also another repeat guest. So Dr Kirk Howatt. Welcome back to the podcast.
Good morning. Thanks for having me. And like you said, I'm in Fargo. I'm actually about 20 feet from him right now, just around the corner, in the same suite. So I didn't have to go very far to sign up for this podcast,
and kind of the same suite of questions we ran by brand. So what's your role here at NDSU and and why do we have you come on for Wild Oat?
Well, I have occasionally worked with Wild Oat as well. It's it is something even when I was in Colorado, when you get to the San Luis Valley of Colorado, one of the biggest problems down there is Wild Oat. And so I've been screening Wild Oat for resistance ever since the early 90s, actually, when I started my grad program, and My responsibilities include the cereal grains and several of the
oil seed crops, a little of the pulse crops. So I I have become very familiar with Wild Oat and we have about 13 acres of manicured Wild Oat pressure, 100 plants per square foot, easily. And this year, because of the weather, everything germinated.
And so maybe we'll start well, we'll start history, and then get into the biology. Some do want to start with just the history of Wild Oat, and we'll have a focus on the Canadian Prairies in the northern Great Plains. I know we can, as Kirk just indicated, find it in many other places, but particularly our geographies up North. This year has been a Wild Oat resurgence for some. Let's start with the history, and maybe we'll start with Breanne again.
Sure. So I actually, because I knew we were going after the history, I dug up the proceedings of the first Weed Science conference in Canada, first national Weed Science conference, I should say, which is the proceedings of a conference on the destruction of weeds by means of chemicals in 1929 and so in the proceedings, they actually do sort of a history of the state of weeds in in Canada. And there's essentially two that come up over and over again, and
it's perennial South thistle and Wild Oat. Now perennial South thistle, they actually had flagged as the bigger issue, because it would blow and move, but Wild Oat was the broader issue. So it's just kind of fun to look back at that and see that, you know, it's, it's not a new weed by any means, it's,
it's a very long term weed. And it's, it's had a lot of focus. I think one of the reasons that it kind of took a step back here there, as as a problem weed in, say, the 80s, 90s, was the group one and group two in crop herbicides made a huge difference, because before that, we were looking at things like Barban and carbine, which you had a half a leaf stage, or ish
to get it on on time, to actually get control. If you look at some of those herbicide labels, the the leaf stage, where they give you that looks like five leaf stages, but it describes about a leaf and a half change in the actual plant for appropriate timing, for control. This is definitely a long term weed. It kind of decreased a little bit with the the in crop group, ones and twos, and I would say in the
last, well, probably 2025, years. It. It's had a pretty big resurgence with some of the other issues I know we're going to talk about in terms of resistance,
yeah, and if I just add a couple of comments to that same kind of general decline in in the prevalence of it because of the group, one group, two products that were available. But then also, when the roundup ready crops became available, and a lot of people went to glyphosate, the area in North Dakota that is the heavy Wild Oat area, is also the area where a lot of Roundup Ready crops were being used, were being
grown. And so for about a decade, there, after from 2000 to 2010 between the products that could be used in crop and the products that were used in other crops and for burn down situations, people just started forgetting about it. And then this year, another lot of people talking about having these huge wild pressures in fields that they don't remember seeing Wild Oat in for the last decade, because we had just a perfect
year. Wild Oat likes it cool and wet, and because of our weather this year, we had about probably two months of prime germination time for Wild Oat, and it was just really difficult to control all the all of the Wild Oat with a single application in some several of these fields.
So I'm curious, probably one of the reasons I'm weird. But when I think about the history of a weed, I always wonder, like, how did it get there? Because it's not native, right? So, how did it get to these areas?
Well, I would say that you probably find several sources and anecdotes that it came in on with the bags of grain that settlers were bringing from the old country, you know, so you had Wild Oat as a problem. And previously, and Wild Oat has always been one of the more problematic weeds for control in small grains, because the life cycle, the habitat, the preferences, the plant bio types. I mean, they're all so similar that it was, it can be very difficult to manage it with
strict cultural or mechanical type processes. You can take care of a large flush of Wild Oat before wheat seeding with tillage or some other practice, but then we know that there's going to be additional flushes of Wild Oat. They might not be as large or intense, but they're definitely sufficient to perpetuate that infestation, because an individual plant will tower above the small grain crop, and each plant, even under
competition, can produce 150 to 500 seeds pretty easily. So it doesn't take very many plants to continue that presence in a field.
And in talking about that history of it, there's there's papers from the 50s that basically call it a companion crop to the cereals. So like Kirk said, when when seeds were coming in. It was just coming right along with it, and that was just, it's was perpetuated. It's having had to clean Wild Oat out of wheat. It's not an easy removal, necessarily. That takes tweezers and time to do a fully thorough job of that, right? So,
yeah, and even light infestations can reduce the crop yield by 10 to 15% or even 20% in some crops, we can definitely have situations where you've got patches that will will essentially drown out the crop, and there might be some wheat in that mass, but it's not harvestable, and people will go around it because they don't want to put all that Wild Oat seed through the combine, but then that's one of the reasons. I think you were mentioning brand that you had Wild Oat and
perennial sow thistle. Well, perennial South thistle gets a lot of attention because it is perennial and and it can blow and it can move into new areas, but it still stays fairly sparse. It takes quite a while for a dense patch to form, whereas, with Wild Oat, it only takes about two years for an individual plant that is not controlled with resistance or for some other reason, to create a 30 foot wide diameter circle that is so intense that the crop doesn't have a chance.
Yeah exactly. I fully agree. And it's kind of entertaining looking at the proceedings in the literature, because perennial South thistle and Wild Oat, we're both up there, and then perennial South thistle kind of disappears and it just stays welded.
Yeah, we have had, we have had a couple of large survey. In North Dakota, one was done in the late 1970s and the other one was done just after the year 2000 and the you know, even from the late 70s to the year 2000 we really didn't have a lot of resistance involved. And we had the introduction of the group one herbicides, and even maybe the very beginning of the introduction of the group two herbicides that could be
used in wheat. But in that 20 year time period, the prevalence and incidence of Wild Oat in North Dakota really did not change, and it could be found on basically a third of the field sample areas that were inspected in the survey had Wild Oat pressure. And those pressures, even after herbicide application late in the season, were were in the range of, I think, if I
remember right, 10 to 15 plants per square meter. It could be that high so, and that was even really before we had a lot of resistance, that's just the biology of the Wild Oat and its drive to survive.
We've got similar surveys, and it's it's unusual for Wild Oat not to be one of the top three across all the Prairie Provinces from the 1970s on.
Yeah, yeah. In North Dakota, the number one we take tends to be green foxtail. Yeah. But for for us, at least in in the small grain market, we can have pretty heavy infestations of foxtail species and still get essentially 90% grain yield, yeah, exactly 90 to 95% it's very difficult for us to document statistically yield loss from foxtails, but you get a handful of wild oats in the field, and it starts to reduce the yield and quality pretty quickly.
So we've already started down the path of biology. I think we're going to stay parked there for a while. So usually when, when Sarah and I are talking about individual weeds that we hate and have to deal with, it's these small seeded 10s of 1000s to hundreds of 1000s of seeds per plant, type of things like kosher the pigweeds. That's also my setup there for x. I know Wild Oat will have a different number and
some different stories there. But why don't we stick with just the biology of the plant itself, and then how that also helps it fit in? And we've discussed some of this, but how it really helps it fit in and thrive in these geographies, and why it's continued to be a problem. And so maybe we'll start with Kirk this time.
Start with me this time. Well, as you were talking about that, one of the things I was thinking of was the tillage system. And because Wild Oat has such a large seed, it needs to be buried in the soil a little bit deeper. It needs to have good soil contact. And so those tillage the conventional and even some of the minimum till systems allow for that seed
burial. But even in no till environments, Wild Oat has this wonderful adaptation of the on, with that twisted kind of a helical twist in the in the awn, that gives it the characteristic bend, 90 degree bend about halfway through. And once that on gets wet, the that helical twist starts to straighten, which causes a corkscrew action in on the soil, in with the seed, which helps it find little cracks and crevices and whole
holes. It kind of almost burrows itself into the soil to get that soil contact and access to more moisture, because right at the surface, yeah, it just the seed stays so dry it won't germinate very well. So it has that adapt, adaptation to help it get into
I feel like every Weed Science graduate student the soil. should take videos of adding water to wild oats before being gifted a degree.
You know grade school kids love it. You get the early grade school age. You give everybody their Wild Oat seed and the little squirt bottle of water and say, Okay, we're gonna have a little race. And everybody starts squirting their Wild Oat seed. And as it twists, some of them go lengthwise, and some of them just go in circles, but they have lots of fun squirting Wild Oat seed.
Yeah. I called it a dance party. We did dance parties with wild oats.
There you go. Yeah. Oh, man, if you had a, if you had a little handful of Wild Oat seed and just water, they each got a little pile, it'd be like a mosh pit.
Man, exactly.
Rock and roll weeds. There we go.
Yes, that's definitely. The unique characteristic of the seed itself that I think does help it separate it from some of the other weeds that we kind of talk about on a annual or daily basis. But what else about seed, seed production? Just keep Yeah I was gonna continue on with that. Then you started
talking to especially on the seed production. So I had mentioned, we're only talking a few 100 seeds each, but though those seeds are large, and one of the things I talk about with my class is that we have R strategist and K strategists, R strategists produce lots of seed to make sure some of the offspring survives. And K strategists typically are delving into this. perennial plants that have an individual that will survive,
like perennial South thistle or Canada thistle. But even within the R strategist, Wild Oat is kind of a K strategist, because it puts more energy into those individual seeds, into into the individual offspring to ensure survival of the plant, and can perpetuate that in the in the in the soil. Now the other side of that whole perpetuation thing is, well, how long does the seed
last? We really have a benefit with kochia management, in that 98% of the seed will either grow or die within the first year.
But because of the larger stature of the Wild Oat seed, the fact that it's got that more of a case like structure around it, the is more makes it more resilient in the soil, it's more difficult for microbes to degrade it, and it's more I mean, it's going to be more attractive to rodents, because it's a good energy source, but that large seed allows it to persist in the soil, and how long it lasts depends on what you are, what article you look at, but anywhere from five to 15
years. So yeah, you can have really good Wild Oat control for several years, and then have an environment that stimulates a major invert, emergency vent, and you see that resurgence of the plant in the field
again on along with that, how deep those seeds are buried can also affect how long they last. So I know when, when moldboard plowing was a bigger thing up here, there was sort of the thought, well, we'll just bury it way too deep. It won't be able to emerge and well, we won't do it very often, like we'll do a really deep burial every 10 years or so. Well, they'd come back and do another deep tillage 10 years later and bring back a whole bunch of viable Wild Oat seed.
It would just, it would still be viable because it had been buried deep enough. Yeah. The other thing with Wild Oat is they can emerge from depth. They can emerge from 10 to 15 centimeters down. No problem. So you, you have to bury it real deep to actually, oh, I went centimeters. Sorry, guys, my bad. But it can emerge from way down there without a without an issue. You got to bury it pretty dar deep to actually
15 centimeters, 6 inches.
Yeah, right, yeah. Whoops. Metric mind! That's another pretty unique one. You know, some of those smaller seeds. You bury it two inches down, and it's, it's not going to come out of the ground wild oat is just like, oh, sweet moisture in a week. So, right?
And the other thing to realize is that, you know, we talk about burying the the seed, but we don't always bury it as deep as we think. And I know when we are incorporating herbicides, I always tell the students, if you want the herbicide zone to be an inch and a half deep, two inches deep or 10 centimeters, right? Oh, five centimeters, five centimeters. Yep, five to seven centimeters, then you have to work the soil
twice that depth. So if you have a moldboard plow that inverts a slab of soil six inches deep, a lot of that seed is going to stay in the stop in the top three inches of soil. And yeah, so we're not burying it as deep, and we're putting it into an a zone within the soil profile that is really advantageous for emergence of that species, because it's got the huge energy reserve and is able to emerge from like was mentioned, several inches or lots of centimeters in the soil,
Exactly then. One of the other things you kind of mentioned Joe was a little bit about the biology and how it fits in our cropping systems in Western Canada, 9095 Percent of our acreage is spring annual crops. That's what we grow. It's wheat, canola, pulses, that's That's it. We have a small acreage of winter cereal. Sorry, Sarah, but that's all we got.
And Wild Oat fits perfectly in as a spring annual so you will have some that come up early, and you catch them in the burn off, like Kirk mentioned, but a lot of them are more than happy to come up after you've seeded the crop, or that motion of seeding provides that little bit of burial to get them that seed soil contact. Now you got a flush coming. They flush through the season. So you get precipitation events. You'll get additional flushes of Wild Oats coming, and then they mature and
drop their seeds, typically before we harvest the crop. So your, your actual sort of time range to attack that that weed is very, very short. It's within that crop growing season. So, you know, there's some weeds where it's like, you know, you can try and get a little bit of control in the fall or or things like that. You know, Kochia seed matures, typically after the crop matures, is there some ability to get in there? Then
Wild Oat doesn't really give you that opportunity. It's, it's right in that grow season of the spring annual crops.
Yeah that's, that's one of the other things I was going to point out. You just made the comment that either the harvest really fits or the seed is mature before we harvest wheat, and so it's dropping. It's not even a lot of it getting into the combine. But even the pre harvest desiccation does not shut down the Wild Oat plant prior to viability of the seed. So other species that pre harvest desiccation treatment can reduce a lot of the seed viability that's on the plants
that's already been produced. But with Wild Oat it's already far enough along in development where you, you don't, we don't have that same effect.
We did a study a few years ago, trying to look at when those Wild Oat seeds actually reach viability. And so we started when the panicle emerged, or the on average across the plot, panicles were emerged, and then cut weekly and kept those seeds and let them dry down within a week after panicle emergence, in some cases, you have up to 30% seed seed viability after you let them dry down like it's it's ridiculous. Yeah,
that's crazy. I know with some of the small seeded weeds, like the pigweeds, waterhemp, you know the lot of people are dealing with that now, I've seen some information where that seed is viable two weeks, 10 days to two weeks after the flowering happens. So, you know, people are looking at Green plants in the field thinking, Oh, I gotta kill this before the seed is viable. Crop plants are the only ones that have a hard time finishing off their seed. Weeds do it very quickly,
yeah, and that time span between the panicle emergence and the seeds starting to drop off because they're already mature, was, I think, five weeks on average at three locations. So that goes, that's from the panicle actually emerging, including anthesis, including seed fill, including dry down, like that's it. You got a month,
yeah. So in between that pre plant burn down and your harvest type situations, we really have one shot. We have two shots. We could have two shots if people were willing to spend the money, but we really got one shot to try to kill things, right? So, and we have group one and group two herbicides. Breanne, do you have any any recommendations or suggestions for timing of applications with these herbicides used in crop?
We see a little bit of a tendency up here for producers that try and wait, wait for more of those wild oats to emerge and and they push it. And once you've got, you know, three tillers, five leaf, three Tiller it's not as effective, not nearly as bad.
It might be on the label. People, it might be on the label, but that doesn't mean that it's the best thing to do,
exactly so, I mean, we've seen better effect with guys going in twice, go in early at, you know, you got some wild oats up at two leaf spray them and then get the later, the later flush, if you can. But then you're fighting weather, hoping Mother Nature is going to cooperate with that, right?
Yeah, and waiting until everything's out of the ground. The first ones are just too big to get effective control and outside of resistance group two herbicides, especially if they are applied later in the window of application, they do not completely kill all the plants, and the plants produce seed that is. Viable, not necessarily resistant, but it is still
viable and perpetuating that that environment. I know with us that oftentimes I'll tell people, if it's hot and dry, group two herbicides work a little bit better than group one herbicides. If it is cool and wet, that favors the group one herbicides. The group one herbicides tend to be more complete, but when we apply any of these herbicides, they translocate to the growing point. And if there are multiple growing points on the grass plant, the herbicide has to divide it itself, right? You get,
you divide and conquer. Yeah,
divide and conquer. And you don't have as many people in as many army, individuals, the herbicide molecules going to any particular fight. And we want as many people in the fight as possible. So if we can apply before tillering starts, then all of the herbicide that gets into the plant goes to that one
growing point. If we have two or three tillers on the plant, we will pretty much always kill the main tiller, main shaft, because that's where the majority of the product is going to go once that part of the plant is not pulling in a lot of moisture and nutrients to to grow, then the herbicide can start go to those going to those other places, but it's a less amount of herbicide because It's being diluted across multiple growing points, and once the plant starts to suffer effects of herbicide,
translocation tends to decline. So even if the herbicide is in the plant tissue, it won't always be able to move to those side tillers. And those side tillers with a group one herbicide. They can get up to be three or four feet tall, a meter or more for those of you north of the border, thank you and and
produce relatively normal looking seed heads. The herbicide does not continue to move up into that inflorescence when the new panicle is developed, and so we get really huge seeds, really strong viability on those seeds at the end of the season.
Yeah, I think overall kind of is a testament to how
It was something, Anything's better than nothing. well some of those group one and group two products have worked compared to when we started, and Breanne was mentioning kind of the first post emergence products for wild oat control. One leaf, you're good. One half leaf, that's the perfect stage. Two leaf, you're too late. And we were okay using those, because there was something. And then phenoxapprop came along with Puma for us. I don't know what it was called in Canada?
It's Puma as well. Yep.
it was still up there. And has just changed everybody's
Yeah that's one of my least favorite grower opinion about growing wheat. And it's just phenomenal for several years. Yeah, and oh, that kind of brings up something else I was wanting to talk about a little bit today. We talk about group one and group two, but there's a lot of genetic calls to take, is I sprayed this it didn't work. What should I variability and some weird things happening within Wild Oat because it's hexaploid Instead of just diploid, and we see in
spray? And it's like, I got no idea. our screening characterizations, resistance to one group one
Oh, hey I got a better one. They call in, they herbicide doesn't necessarily mean there's going to be resistance to all of them. And I know with ryegrass in Australia, they were able to generate a very consistent hierarchy. We can use this group one until it doesn't work, and then this one's a little bit more effective, so that one works for
a while, and they go through the whole stages. And if somebody started with the most effective one, which we can't use in wheat, clethodim, once that had once you had resistance to that product, it was resistant to everything else, even if you never used the other ones. But with Wild Oat, we've got very diversified characterization, and phenoxyprop works, but clodinafop doesn't. And in another field, clodinafop works,
but phenoxyprop doesn't. And so trying to help the growers understand the characterization within their field has been something that that we've been trying to provide over the years, and unfortunately, we're getting to the point where even the non selective products like the assure two or clethodim type products, they are not even controlling the entire population of wild oats. So we are. We are running out of the.
Uh, in crop applications to manage wild oats. Yeah, say, I sprayed this product three times in a row because it didn't work the first time. Now what do I do? Yeah, well,
Youir might have resistance.
Yeah, you might have resistance. And now your plants are too big. They can't you're not. Nothing's going to control them. So, yeah,
that's, that's a fun one to explain to growers, is that that explain nature, and the different mutations confer differences between the fops, the dims and the dems, and sometimes even within those and like, it's, it's complicated. It's not as easy as just this didn't work. So that will right? Because it could be a different mutation, or it could be metabolism, and none of them will work. I don't, I don't
know, right? So we, we get a little bit of flack sometimes for pushing to just send your samples in and get your resistance test done. Like, it's better than nothing. It's still not perfect, but it gives you an idea of what might work in your population, because I can't tell just by your history of here's what I sprayed. What should I spray now I don't know, right? It's not that easy.
And unless we're talking about the metabolism resistance, the resistant characteristic, the risk resistant biotypes develop separately. So typically, if you've got resistance to group one, group two, products still work. If you have resistance to group two, then group one
And so that's get these questions all the time products still work. And even in some fields where where we see resistance to both chemistries, both groups of herbicides, is I have, excuse me, I haven't had a situation yet where I have found multiple resistance within one plant. So on the early stages of this mixture resistance developing, you have individuals that are still susceptible to group one and some that are
still susceptible to group two. And so we have had very good success with a sequential treatment where we I like to suggest people start with a group two herbicide, because that the plants need to be smaller. It works better on smaller plants than larger plants that doesn't fit with its environmental profile very well, because I said those group two herbicides work better when it's hot and dry. You're earlier in
the season. We're usually, usually a little bit wetter, and those group two products don't work as quickly, but they still tend to be effective. And then we come back a couple weeks later with a group one herbicide on those plants that survived.
The group two, they have recovered, and they're they're back to actively growing, and they're a little bit larger, but we have a larger window for the group one herbicide to be effective, and in those scenarios, if we have 40% control from a group one or a group two, if we tank mix the two, we get to about 80% control. And if we do a sequential treatment, we get above 90% control. We're back up
to the typical expectations. So it's like, like I said, if you can afford those two applications, there's some strategy to try to make ends meet. from agronomist and one of our county agents asked me the same question yesterday, of, yeah, we generally understand that resistance is increasing, but we sent samples in and you told us that every product tested controlled it. So why did my wild oats survive that application?
Yeah, and in some of those situations, we rescreen their stuff, and yes, yeah, everything completely dies. So we got to look at some maybe environment when they applied, or maybe it was a secondary flush, not a, you know, we'd have very minimal soil residual activity from these post
emergence products in wheat, at least. And if the environment is conducive to rapid growth of the Wild Oat, if you're if you're not back in the field for a couple of weeks, you might think that it was an escape plant when it's actually a late emerging plant.
Yeah, I would agree that that highlights the criticalness of scouting after a herbicide application to understand if, if it was a herbicide failure or potential resistance, or if you've just got a new flush coming. Last year in Canada, we were really, really, really dry early in the season, so a lot of our cereals headed out in June like we were massively early. Then we got four or five inches of rain in
the next. Two weeks, and everything started tillering, and we had flushes of Wild Oat coming up, but because we were headed out, we couldn't spray right. So the crop was already headed but I think people underestimate how many wild oats can actually emerge middle to end of June, sometimes with with a good rainfall.
So do you have any suggestions, Breanne, for a residual product that might be helpful in the wheat program?
So we've seen, we've seen a resurgence in the use of triallate. Up here, some misunderstandings, where it's a new product, in which we have to go? No, no, no, no, this is not a new product. This is an old product. We've also seen some suppression from things like pyroxasulfone providing some assistance, at least in in some of those situations. I would say triallate is the one that's that's research the most for,
for residual product. We've had to do a lot of communication around that, though, because we've had triallate resistant wild oats in the prairies, particularly in Alberta and in central Alberta, it was very common in the 90s and in so John O'Donovan was, was the scientist here at a Canada that had found the triallate resistance here. He was one of my predecessors here, and so I talked to him shortly before he retired, when we were starting to hear a lot more about, hey, I'm going to
I'm going to use triallate. It's going to solve all my resistance issues. And he's like, there was no fitness penalties with that. I looked at that. There was no fitness penalties that I could find with that resistance, or there was a little bit, potentially, little bit of a fitness penalty, either way, he said, I don't expect that that biotype to have gone too very
far. So on some of those fields that had a significant population of triallate resistant Wild Oats, he's like, I bet they'd have maybe five years before they start dealing with triallate resistance again. And I'm already getting calls from growers with, you know, I've got this much group, one and two resistance, and I've got triallate resistance too. What do I spray?
They've got the issues.
How can we talk IWM? I can talk to you about that, because I don't got anything for you on, on what spray at this point,
right? It was, yeah, was that resistance, metabolism? Do you remember,
there's some discussion over that. What John had seen was actually an increased growth rate. So it seemed to be growing through the herbicide layer more quickly, so then it had less absorption, so he was seeing a faster germination, less dormancy type. Type mechanism essentially, whereas there was another group that was arguing it was, I believe, metabolism based, but, and I don't think there was ever fully a consensus on on that mechanism as I understand it.
When I asked John about the one paper I read, he, he, I got an earful about the work that he had done and the work they had done, and etc. So, yeah, yeah, yeah.
And as far as our Wild Oat, I know that was back John Nalewaja was here, did a lot of work with it, yeah. And he didn't feel that we really had resistance in this geography, it was more limited incorporation activities, you know the improper incorporation unfavorable environments, because if the soil is wet, when you're applying that and trying to incorporate it, you don't get good mixing of the of the soil.
And if one of the things that has come up more recently with a lot of the newer tillage implements is that they don't necessarily mix the soil. They kind of throw chunks around. So
it looks like a lot is happening. But I've had a couple of people call me and talk about it, and they said, Well, yeah, it doesn't look like the triallate worked at all, and they sent us seed and we killed it all in the greenhouse here the comments earlier, but the fact that incorporation of that product is so critical to good activity, and I know for us, when we've been doing work, the Spring application of the liquid
double Incorporated. It's like 99% control. I mean, even in our research block, where we've got that solid lawn of Wild Oat, there's maybe one or two plants at the end of the season that have a seed head up above the crop.
And that incorporation requirement, that's been an interesting conversation with some of our die hard no tillers that we've got camps up here. We've got our die hard no tillers. We've got our occasional tillage it was okay, or some minimum tillage is our die hard no tillers are having a real rough time with with the idea of having to add some tillage for incorporation. Question is, there's been a few My head got chewed off once or twice when I suggested a pre
product take those things. Yeah, we also see some of you know, we actually, in some cases, are pushing for a fall application of some of these things, just so that you get the spring moisture. Our spring moisture has been so hit or miss the last
few years, but we typically have some snow melt. So if you've got it down in the fall, at least, you get that snow melt moisture where, if you're waiting for the rainfall, there's been a few years lately where you have not gotten it until your crop is, you know, seven leaf and, yeah, there's no weeds coming up. Anyways,
I know with our labels, the triallate chemical is available as a liquid called Fargo, and then we have the granular application, which is avadex. And so the avadex for us, at least, has the the label to allow spread on the field in the fall with no incorporation do that as late as possible, before snow or rain event, so that you don't lose as much of the of the triallate from the granules and I like as far as wild oat control, you had the Spring application of triolate
Double Incorporated. Almost everything is dead. The fall application for us has worked. I can be about 90% control.
Sometimes it's a little bit less if you don't get that physical mechanical incorporation, but at least it is an option for those really dar Die Hard, no tillers, but it definitely has to be on in the fall because you need enough moisture, even if it's in multiple events, to get the herbicide out of the granule, and then additional moisture to get it moved into the soil, so that we capture it in the soil Where The Wild Oat shoots can grab onto it and be exposed to it as they're coming through the
soil profile, but it's definitely because you're relying a lot more on environment. It's much more variable in benefit. You know, some years it works quite well. In other years, it's like 60% control. I don't know if I really like that or not, but and we were seeing the same thing.
You had mentioned, zidua (pyroxasulfone). We had always been working with it in the spring, because that's what the labels said, and that's when the company wanted to use and we would have years where I could see 80% control, and a lot of years where it was 20 to 30% control, so we had a student do some uptake work with it as far as site of the plant. And none of that herbicide gets in through the vegetation, essentially so Fargo triallate avadex, that chemical absorbs
into the plant shoot as it's coming through the soil. But we need to get zidua down to the roots of the Wild Oat, and with the comments earlier how deep it can emerge. And zidua chemical itself is rather water insoluble, and it ties up with soil really well, so it takes a lot of rain. If we had a three inch rain event, we'd get 80% control. But that doesn't happen very frequently. We put it on in the fall, we could still get enough winter snow and spring snow melt, and we'd get enough
herbicide. So in talking with individuals as well as our own research, we get on an average of 85% control from that fall application, but you need to use four ounces of zidua product that that four ounces is kind of expensive, but we can get into that 85% average if we cut the rate back to three and a quarter, which is where the company was hoping to position it, then instead of 85% control, we get 70 to 75 and if you cut back to two and Three quarters ounces, then you're down below
60% control. So I mean, there is we can kill. I think what we're basically doing is killing the really shallow seeds. But in order to get the herbicide to move down through the soil profile, we need more to start with, so that we get more down into that three to four inch zone, which is where a lot of the Wild Oat is probably coming from,
and that work you're just describing, Kirk set, in the absence of a spring tillage event, is that encompassing, if you also have spring tillage. After that fall application,
yeah, it seems to be quite durable across pretty much any environment. We don't have a lot of experience, as many points of experience with no till, but on a lighter soil, with no till in the fall, we still get that 75 to 85% control, I would say, pretty regularly, but on cultivated areas, we have cultivated in the fall and then applied. We have applied and then cultivated in the fall. We have, we've we've
applied in the fall and then cultivated in the spring. We've applied, we've cultivated in the fall, applied in the fall and then cultivated in the spring. I mean, we've done, I think we've caught pretty much any scenario, and depending on the particular year, one specific scenario can be separated from the others, but they tend to only be differ by about five to eight
percentage control points. So it's it gives the grower the flexibility to apply it when they want to in part of their applications of fertilizer, or some other things that they're doing, gives them a lot of flexibility, I think, from what we've seen so far in when it goes on the ground as long as it's on in the fall.
To talk quite a bit about herbicides for Wild Oat control. And one thing I wanted to point out, to highlight the Canadians and some of the great things they do, is there is a Wild Oat resistance committee. What is that about?
Wild oat Action Committee?
That's the correct way.
Yeah. So actually, if you look back to, I think it was about the 70s, there was a Wild Oat Action Committee at that point in time as well. And they had, they had a mascot. It was Wild Oat bill. And yeah, there he was the great grain robber and all these kinds of things. And it kind of they did their final wrap up as the group one herbicides came out. So the group one herbicides were really positioned as that
solution in a lot of ways, to Wild Oat. A few years ago, we had a farmer approach some of our Canadian Weed Science Society members and really push for a resurgence of some form of the wild oat Action Committee. And that started the resistant Wild Oat Action Committee. So it is made up of scientists, farmers, agronomists, industry folks, some of our extension or research representatives from some of the commodity groups.
And the goal, we've struggled a little bit with where we fit, because the resistant wild oat Action Committee is fully volunteer, and it's not incorporated. It's not a nonprofit, it's just it's a volunteer committee. But in being a volunteer committee, it makes it difficult for us to apply for funding for actually conducting research. And a lot of us on there are conducting research in our full time jobs.
So that's that's been a challenge. So our focus in the last few years has really been on extension so trying to develop some fact sheets, trying to develop some like four pager fact sheets, trying to do some videos, trying to explain some of this Wild Oat biology, trying to bring back some of the integrated weed management work that's been done that. You start talking to producers, and they're like, Oh, do you think that'll have any effect? And it's like, yes, yes, that'll
have up your seeding rate. It's a good thing to do. We have lots of evidence of it. Like, really that's been worked on, yes, that's been worked on, some of those types of discussions. Or, you know, we get the question of, you know, what do I have to do to sample for resistance testing? So we've got an infographic on that. Here's what you got to do. Here's how you should sample. Use a sweep net, way faster than hand stripping wild oats. Walk through a big patch wild oats with a sweep
net, it gets really clean sample. It's great. Some of those kind of tips and where in the prairies it is prairie focus, sorry guys, but it's where in the prairies you can get resistance test done. So what kind of resistance tests they do? What it costs you? We've got infographics on on the various herbicide groups that we have. We have infographics on integrated weed management strategies for for Wild Oat.
We're in a bit of a tough situation right now, because we're struggling for funding again, because we're not owned by any one agency, we're not internally funded, we're not really doing research, so we're struggling to get research funding. But to get extension funding, they don't like to pay necessarily, for personnel, which we have a project manager on board, because the rest of us have full time jobs outside of
it. So it's we're in a bit of a tough spot right now, but in, I'd say, in the last few years, we've done a lot of good work and a lot of information extension trying to get that up. So it's on the the Canadian Weed Science Society website. If you go to Weed science.ca under Resources, there's a link for the resistant wild oat Action Committee there, with all of our infographics, all of our videos. Everything that we've done in
the last few years. So including our identification infographic on how wild oats are like Elvis, which is the closest we've ever gone to going viral, was our Wild Oat as Elvis infographic. So
gonna see, we'll link that in the show notes, because I know we, last time you were on we had to talk about the whole Elvis thing. Yeah, yeah.
Yeah, it's a unique one, but it works really, really good for students, they all remember it even, like, five to 10 years later, they're like, I still remember that. I'm like, that's the point you'll never forget when you look at a wild oats.
Well, we probably should kind of wrap up this conversation here. So one of the taglines of our podcast is a silver bullets are for werewolves, not for weeds. And so Sarah has started us down the pathway. We have to ask the guests the question, do you guys see any silver bullets for Wild Oat?
Nope, that's the short answer.
Not getting any easier. Stay staggered, staged effects. Yeah, you know, I saw that and some of the information that you had sent, and my first comment was going to be that, well, I thought those were for werewolves,
exactly. It's always been my answer. That's why I was able to, able to work it in the podcast. Whenever I get asked that question, nope, not, not the media I read at least
no and yeah, Wild Oat is so adaptable and so variable, and that that dormant seed bank really, really messes with it. You can get perfect control for a year, and it's gonna come right back the next time the environment is conducive. Yeah,
so, and, you know, kind of on that. One of the things I think I forgot to mention earlier is that the fact that, because the Wild Oat has that protective capsule basically enclosing the seed, and it takes a little while for that to break down in the environment, there's John Nalewaja is telling me that, especially in the research plots where he would be working with the same place year after year, he's like he was pretty certain that the seed that was produced this year won't grow
next year, that the Wild Oat that you see next year is probably from two to five years ago, and that's one of the strategies, one of the tactics the plant has to broaden out its presence in the environment, make sure that there isn't a catastrophic event that causes the decline of the species.
We talked a lot about herbicides there, there are integrated weed management strategies that work. Crop rotation works. Increasing your seeding rate works early cut barley silage is phenomenal on Wild Oat, because you're cutting that Wild Oat before it's at seed. Two, three years of barley silage. And you can, you can run your Wild Oat population down quite a bit, depending on your seed bank when you start. But that's one of the biggest things I've seen with
Wild Oat and some of the recent work. Recent work that I've done is that when you've got a Wild Oat population of 20 to 30 per square meter, some of those IWM tactics work slick. When you've got a Wild Oat population of 100 to 200 per square meter, it's not enough. So waiting until all of your herbicides are resistant, and then trying to switch to IWM is not the right strategy to take, because you're going to have way too big of a
population at that point in time. Adding some of those strategies in earlier, while your herbicides are still effective is going to be a much better, longer term strategy. And with our pres up here, we were often looking suppression with a pre herbicide up here because of our organic matters. We've got organic matters of 10 to 12% in in some areas, they we get a lot of soil binding, and so we get a lot of pushback on
the incorporation of pre into our rotations. And it's like, but if, if you knock your population down by 60% and then go in with a group one or two, you've lessened your selection pressure on the group one or two resistance by 60% because you've got 60% for your plants that you're putting it on like it's, it's still very beneficial. But that's, that's been a fun message to try and get through to,
yeah, that the amount of money you sometimes tie up in a pre emergence herbicide. There is often the expectation that it should be complete and thorough.
But you know, you don't always have to see dead weeds or lack of weed emergence to to document that those pre emergent herbicides are working. We have done work in small grains with a few, very few of the things that we have available. And there is, there is very, very little evidence early in the season that this, that they're really beneficial, because I still have plenty of weeds here. I've got to still do
the post emergence application. And the pre emergence applications should never be approached as your entire program. And even when we have those situations where we still didn't look like we really slowed the weeds down, there's still lots of them here. The yield benefit to including that pre emergent herbicide more than pays for the cost of the application and the herbicide that you put on early. So it is an investment, and it is I try to get people to think of it
more as an insurance policy. You got you pay into a lot of insurance policies, hoping that you never benefit from it. But pre emergence herbicides are an insurance policy that pretty much always helps you get something out of it.
Get to see some return on investment. Always a good thing. Great. Well, we probably should go ahead and wrap up here. We could go on for another hour, I'm guessing.
Yep, we didn't even really get into resistance numbers and percentages of populations like man
just means we have to stand again next season. But before we we do go. We always like to give guests the opportunity to say where people can find them. So any social media or other websites point people to and and Breanne, we'll start with you on that one as well.
Sure, I'm kind of all over the place trying to find ways to get in touch with people. I'm on on x @BreanneTidemann. I'm on Instagram @lacombeweedsci. I'm on LinkedIn. I think I'm on blue sky. I'm pretty much everywhere, trying to be in touch. I mostly am posting on x and Instagram and LinkedIn primarily.
And we've got our annual, or not annual weekly weedy Wednesday, weed ID Wednesday. Yes,
it's almost weekly. There's misses here and there as things come up, but most weeks there's a weed ID Wednesday on there for for funsies as well. Yep.
All right, we'll direct people that way and get those in the show notes as well. And Kirk maybe a little bit more elusive to find.
I was gonna say I like to keep things consolidated through Joe ikely, yeah, you can find me if you come to the NDSU Department of Plant Sciences page. But I'm not really out on social media, so I assist answering questions that come into through the extension service. So Joe gets, gets to see him first, usually,
yep, and then we'll, we'll also post. We have a lead science web page, and we've got, I think, 50 years of Wild Oat history up on that page currently, all the herbicide testing, at least within our NDSU system. Yeah,
there's a lot of information there.
Well, we will again, thank the both of you for your time today. And again, we might just have to do this again in the future to to really cover Wild Oat and the depth it deserves.
Sure sounds like fun.
I'd be in All right, so again, thanks. Thanks to our listeners, and we'll catch you next time on the War Against Weeds podcast. Have a good day. As always, we thank you for listening to the war against weeds podcast. Just another reminder. You can find our podcast hosted on the Crop Protection Network, or CPN, for short. So this is another great resource that's driven by extension, scientists at different universities for pest management, and with that, we will see you next week on the
war against weeds podcast. You.