Weed science society of america
Jodi:
Welcome to the Successful Farming Podcast. I'm Jodi Henke. Joining me today is Lee Van Wychen, Executive Director of Science Policy for the Weed Science Society of America. Lee, what is this organization all about?
Lee:
Weed Science Society of America is a non-profit professional society that promotes the research management of noxious and invasive weeds and cropland weeds in natural and agricultural settings. So we have members from Academia, from the Land-Grant Universities Research and Extension of Teaching, also from industry several consultants and crop water land managers. So pretty diverse group, but we're all concerned about weeds. So we get a lot of strange looks sometimes.
Jodi:
Oh, you guys aren't the only ones concerned about weeds. I think everybody who grows anything out of the ground is also concerned about weeds. So how do you guys develop research priorities?
Lee:
We have a research priorities committee. And so from that committee, they go through every year and survey the membership and try to keep up on current and future topics of interest. And so a couple of the more interesting things that have evolved are weed genomics and then precision ag technologies. And so we've been trying to advance and push those initiatives, and those are some fascinating up and coming areas for weed management.
Jodi:
Can you give me some examples?
Lee:
Yeah, sure. So across the country really, weed genomics was barely on anyone's plate a decade ago. And we did have some weed geneticists within the discipline, but that has been expanding rapidly. And so there's initial research that shows that we might be able to use some of our most successful weeds like Palmer amaranth and waterhemp, separate male and female plants. And you can use genetics, gene drive technology to make the male plant sterile or plant seeds that would make them sterile. This is in theory, the work has been done from the science end of it, but we still have a ways to go, but you can have these male plants out there crossing with the female, the fertile ones, and then they'd be sterile and you could drive the population down that way.
Lee:
So it would be almost like a new paradigm of control, we have mechanical control, herbicide control, cultural crop rotation, those type of things, biological control, but this would be genetic control. So that's an exciting area that we're slowly diving into.
Jodi:
Would this be something that the farmers would have to work with? How would that work with the genetics?
Lee:
In theory, you would have to plant one of these sterile male plants out in your field every 100 feet or so. You'd have to do this over a number of years, but then you can slowly drive that seed bank population down to zero or near zero, if that's possible. You always have birds and animals or combines and stuff bringing new feed into the field. But yeah, that's one exciting new research area that's on the horizon. The other being trying to advance the site specific technology where you're recognizing the different gene in the crop versus the weed in real time, and not just spraying them with herbicides or using mechanical, but other types of weed management or weed control tools as electrification. Some research is going on there. Using lasers, just use cooking oil, hot oil, you name it. There's flaming. There's lots of different ways to try and attack these weeds.
Jodi:
Cooking oil, whatever a farmer can find to kill these things. You never know what may be the next breakthrough along with genetics when a farmer needs to control the weeds. But what do you think is the most needed breakthrough in weed science or technology that would help us control weeds in the fields?
Lee:
Well, I mean, we see resistance management as still the number one driving issue across the discipline. Growers like to use herbicides, for the most part they're very affordable and effective and easy to use, but we have to get this message out to the grower community. Yes, it's going to cost you more upfront to manage these weeds, using an integrated system, you can't just spray the same mode of action herbicide every year and expect not to get resistance. It's basically guaranteed that will happen if you do that. So you have to have an integrated approach, not just with weeds, but any pests for that matter. We have to give them that mindset not to do that, to keep diversifying our strategies.
Jodi:
Lee, we talked about messing with the genetics in weeds such as Palmer amaranth to help control them. What other research is going on are there even more at the molecular level, maybe some from other countries, what do you see happening right now?
Lee:
So at the molecular level, and unfortunately that funding is very hard to come by, the research funding, things like molecular tools to regulate bud dormancy genes and perennial weeds, can we control when they go dormant or when the seeds germinate, those types of things and can we start to change some of those characteristics that would make the weed easier to control? Especially in some of our perennial weeds and so forth. Our commodity groups, they're very supportive of the research, but from a federal public funding level, those insects and pathogens, they're much more “sexy”and you get butterflies and all that stuff. So yeah, the weeds, we're on the tail end and we could definitely use a dose of research funding to help go after some of these basic research questions about weeds.
Jodi:
So who does the weed research? Is it spread out around the country?
Lee:
Yeah. Most of the Land-Grant universities have weed scientists, weed researchers. Some departments and programs are bigger than others, depending on the crops and the agricultural priorities. Out West, you have a lot more public lands and so those tend to be smaller programs just because you don't have the agricultural groups and commodity groups that help support that. And then you have the industry folks and so of course we've seen the consolidation within the registrant's, as I refer to them, because I worked with EPA oversight, regulatory issues. We're down to three or four or five big ones, so those researchers, a lot of them that do development research and weed products, there are a few herbicides that are in the pipeline that are five to 10 years away. We'll see where that goes.
Jodi:
In your opinion, Lee, which weed is a farmer's greatest enemy right now?
Lee:
Well, we've been talking about them already, hope I don't offend my members because if I'm in the Midwest, I better say waterhemp's the worst weed out there. But if I'm in the Southern region in particular, Palmer amaranth is without question the number one. Of course, they're kissing cousins. They're both in the Amaranthus family and they're both out crosses, so they both have separate male and female plants. And they have taken off in, pretty much since the introduction of Roundup Ready Crops, they have grown exponentially in their importance. And now they rank on the top every year. The most common and troublesome weeds. Palmer amaranth and waterhemp consistently are at the very top of that now all the time. And it's because of their resistance issues, basically.
Lee:
There's waterhemp in the Midwest that's resistant to six or seven different herbicide modes of action. And that's getting basically to the end of a list of effective herbicides. So Palmer amaranth is just a behemoth in terms of its feed production, photosynthetic use efficiency, nitrogen use efficiency, it's got a lot of desirable characteristics that most crops would love to have. Just out competes everything. It's just a very good survivor and it's spreading like crazy.
Jodi:
What are some of the more common myths that you guys always hear and you know aren't true?
Lee:
Well, the one that's been the biggest thorn in my side is the super weed myth, where we actually have online dictionaries that still refer to these super weeds, I think it was the Oxford dictionary. Weed which is extremely resistant to herbicides, especially one created by the transfer of genes from genetically modified crops into wild plants. And that's just flat out wrong. And this is the definition of a super weed in the Oxford dictionary. So we've put together some fact sheets and so forth to discuss why that's not the case. Now, if they don't want to call Palmer amaranth or waterhemp a super weed, it's a super weed because it has a lot of characteristics that make it a superior competitor to most of the crops. Plus, it has some inherent capabilities to metabolize herbicides and find ways around for resistance those herbicides.
Lee:
But it's not because they received some traits from a genetically modified crop and that's an absolute myth. There's very few crops that actually out cross with any weeds of any significance, maybe some of the canola, there's wild canola, but those weeds have not become any type of a major issue. I think sunflower has ... there's a wild sunflower relative that's considered a weed. The genetically modified crops are not causing super weeds.
Jodi:
Any other myths that you would like to squelch?
Lee:
That's pretty much the biggest one. I hear a lot of different facts about herbicide use and weed control and conventional systems and organic systems and that type of thing. But one of the actual myths is that there's no herbicides used in organic agriculture, but for the most part, they have to kill a weed somehow. So they rely more heavily on crop rotations, but there's a level of mechanical tillage and they still have some natural weed control chemicals that they can use. So when it comes down to managing weeds, it's really all about using an integrated approach and changing up your tactics, having a good crop rotation, whether you're conventional or organic. For the organic guys, hats off to them, it's a very intensive management situation to try and control those weeds, and that's why more people don't do it because even under the best scenario, sometimes you lose to the weeds. You have to terminate your crop or you lose most of your yield. They're ever present, the weeds that are out there, and well, I know they're the biggest limiting factor in organic agriculture production, so that's what shows up on their surveys.
Jodi:
Getting deeper in the weeds here, no pun intended, I guess. I'm sorry, I couldn't resist. When you guys are doing your research, how deep do you go?
Lee:
Well, like we mentioned before with the molecular level, and we're starting to map the entire genomes of some of these species, I believe they have six genera of weeds they actually have placed all of their genetic information so we can start to characterize different parts of that genome and discovered their origins and spread and all kinds of fascinating things. And Palmer amaranth has a very high photosynthetic use efficiency. It does better at photosynthesis than most of the crops it competes against because that's just built into its genetics so can we identify some of those mechanisms and actually put those into our craft. So there's lots of information, that's how deep we're getting into the weeds.
Lee:
And some of the other pest disciplines, entomology, plant pathology, they're much farther along of course just because they have more funding available, but we're trying to fully get that funding increasing, the funding for other pest management disciplines like entomology and plant pathology. However, we're starting to catch up a little bit and we're excited about some funding from USDA, from the National Institute of Food and Agriculture, helping support a weed genomics conference this fall on September in Kansas city. That's tentative yet. It will happen at some point, regardless of what happens with COVID, but we're seeing some good movement towards that direction to try and identify genetic traits that make weed so successful.
Jodi:
Tell me, when a producer, farmer, rancher goes to your website, the Weed Science Society of America, what will they see and how can they use it for their advantage?
Lee:
Well, we are in the process of updating our website. We have headlines of our most recent information, pertinent to the discipline and to the members, but probably the most applicable part would be the section under weeds. There's a ton of information under the weeds tab in terms of identification, lots of information on herbicide resistance. There's the take action group out of the Midwest. Well, they're all over the country now on herbicide resistance management, teaching farmers or growers and applicators modes of action and sites of action to prevent resistance. There's information on the actual herbicides themselves, and lots of other tools that should be helpful links to find resources to better manage the weeds.
Jodi:
We're coming to the end of the podcast. Lee, are there any other tips or advice you'd like to pass along?
Lee:
Well, first and foremost is to rotate your herbicide modes of actions and use an integrated approach. It's almost guaranteed that you're going to have resistance if you do the same thing, spray the same thing, five years, 10 years in a row, you're going to put enough selection pressure on a population of a given weed species to create resistance. So you have to keep changing up those tactics. And this goes back even to one of my favorite examples is back when they hand weeded and still hand weed rice in Southeast Asia and there's barnyard grass which is very similar to rice. Over the course of, I don't know if it was decades or maybe even a century that the barnyard grass adapted to look exactly like the rice. And so they didn't know if they were pulling out the rice or the barnyard grass.
Lee:
No matter if we're pulling them out ourselves or spraying a herbicide or what have you, weeds are survivors, so you got to change it up your tactics. That would be my number one tip. We'd always love to have a little bit more research down so we can work on some of the problems and solutions. So if you guys are out there and you're working through your Commodity Boards or grower groups and what have you, I know weeds always tend to be down the list, but if you can mention that, "Hey, we need to get some more research for weed plants research." That'd be very appreciated.
Jodi:
Thanks to Lee Van Wychen of the Weed Science Society of America for being my guest, and thank you for listening. For Successful Farming, I'm Jodi Henke.