Entomology, Integrated Pest Management

Episode 13: Integrated Pest Management in Entomology

Join Emily as she talks to Jeff about how Integrated Pest Management (IPM) evolved from the entomology concept of “Insect Pest Management”, and what concepts are often used in making IPM related decisions.

This transcript has been edited for clarity.

0:19 Emily: Hi everyone and welcome back to an episode of Farm Sci-Ed, the show where we go into the science and education behind farming. I’m Emily Stine and today we’re taking a bit of a deviation from our discussions about specific research projects. Instead, over the next couple of episodes, we’ll be talking to Jeff, Nevin and Bob about integrated pest management and why it matters to their specific disciplines.

0:40 Today, we’re speaking to Jeff about the general concepts of IPM and how they apply to insect management. So Jeff, can you explain what the three pillars of pest management are?

Jeff: So pillars of pest management is a reference to Dr. Larry Pedego, who was not the founder of integrated pest management, but definitely one of the key proponents, particularly in the 70s of integrated pest management and and beyond, where he uses a bridge to illustrate the components of what make up integrated pest management. So in his model, the the pillars really represent um the different tools, tactics, and strategies that one can use to manage a pest, which are then built upon foundations of biology, ecology and really the science that feeds into those tools, tactics, and strategies.

1:42 E: And how is integrated pest management ecologically important?

J: Really, ecology is important for integrated pest management. Integrated pest management isn’t possible without a fundamental understanding of the ecology and biology of the pests on which you’re you’re targeting.

And so that forms the basis and the foundation that gives you an understanding of when I say ecology and biology I’m really referencing the seasonality of pests. So when does it occur throughout the season? How does it disperse throughout a field? What is its normal distribution or dispersal pattern in a given field? Does it migrate? Does it overwinter? What are the various life stages, and how long does it stay in a given life stage? What are the birth rates? What’s the normal mortality rate for a given insect or pest in general?

And so those different ecological aspects or really characteristics of of a population, is all information you can use to exploit with those various pillars of of pest management, so you can understand the timing better of when you know an insecticide or a cultural control tool might be used in the field that would basically take advantage of what you might see as an achilles heel so to speak for a given given a given pest species. And then in the framework of integrated pest management, how could you use more than one of those pillars how could we use more than one tool tactic or strategy in concert to develop a more robust resilient long-term pest management strategy.

3:30 E: How do economics factor into making IPM decisions?

J: Yeah, so we talked a lot about ecology and biology, but economics are the third part of that really important equation as to what makes integrated pest management a durable solution, you could say.

So in integrated pest management and particularly for for insect pests, maybe specifically in some pathogens as well, we can state that explicitly in a formula of cost divided by value times injury or damage times a constant or percent control expected from a given control tool or tactic. So that’s kind of wordy, but we have a very explicit formula that we can use that derives basically helps us understand an economic injury level. So for what unit of injury that a that an insect can cause to a plant, the relationship between that injury and the ultimate damage that’s caused to the plant through our research that we do, we can we can understand that relationship and we can extract that condense that really down into that EIL – economic injury level formula.

So that’s where economics fits into it at least from experimental standpoint, and it moves more into the practical as we then develop through research a better understanding on timing. So that we can develop thresholds that allow us to make a decision in the field with a tool or a tactic or strategy in a way that suppresses that that insect pest population before it ever reaches that economic injury level. And then that moves us into really the more operational aspect of integrated pest management, which is having an action threshold and then doing research on figuring out the most easily adoptable strategy for sampling to ultimately then make a decision that’s both convenient and easy and again durable for for that practitioner, grower, rancher, homeowner in some cases.

5:44 E: Can you explain how integrated pest management has evolved from insect pest management?

J: Yes in the late um really the late 1940s early 1950s um following World War II in the development of certain chemistries their um and before that time really their pest management generally was on a calendar basis uh maybe using something like farmer’s almanac or maybe more precise field history, but it was really more more of a calendar and experience based approach for for management. Once more tools became more convenient, tools like insecticides became more readily available, more diverse than what we had in the past, there became more issues with the pervasive use of those chemistries both from an environmental standpoint but really from an economic and ecological sustainability standpoint as well.

So some researchers in California had worked to develop this more economic based model which eventually became integrated pest management to try to incorporate economic factors into that decision making process, So it wasn’t just simply based on calendar or field history or experience but actually using insect numbers or some sort of proxy for plant injury to actually make a determination as to whether or not you need to spend money on an insecticide or whatever the tool or control strategy might be, because in some cases no treatment is the best option not only from the standpoint of maybe the insect – you know they may exist in low sub-economic numbers and may not need to be treated, but in some cases you have various conservation strategies or easements that can provide beneficial insects that you don’t want to reduce their numbers and maybe they’re substantial enough. And in some cases, we have economic thresholds that actually incorporate beneficial insects into that calculus as well, again helping growers make decisions that from an economic standpoint make the best sense.

8:02 E: Can you elaborate a bit more on what you mean when you say adoption of IPM practices?

J: When I talk about IPM adoption I’m really talking about incorporating an integrated pest management plan into one’s practice. And to do that, you need to know it well enough it needs to be convenient for your for your cropping system, for your for your program, that you’re working with and the the tools have to be have to make sense and have to be user friendly, if you will, for for the grower or or land manager.

So when I’m thinking about IPM adoption, I’m thinking about a couple things. At least is information about a given pest readily available? So is there an easy way for a grower or agriculturalist to access the information to even know what the tools are that are available for sampling a pass, to determining an action threshold, to knowing what the different tools are, whether it be pesticides or crop rotation strategies and whatnot.

And then the other part of it I think about are what are the scientific tools that are available, and are they convenient enough for our growers to use? Scientists like to science I guess, you can quote me on that. And so sometimes, our research papers aren’t very user friendly from a practitioner standpoint, and so more work needs to be done by perhaps people with Extension appointments that work with the Extension Service throughout the United States at our land grant universities like the University of Nebraska, can take that information and translate into a way that’s more user friendly for our growers.

So you might have a threshold that I don’t know might use some tools or some counting that actually takes a lot more time and money just to derive the information than to just make the treatment. um And so you know in some cases then more research actually is needed on finding more convenient tools to have maybe lower threshold numbers that you can use to infer how the population is developing or even using convenient shortcuts, tools that anyone might have on hand. Some cases I’ve seen thresholds for things like soybean aphids in the past and using like a quarter from your pocket to estimate, to give you a sampling area for the number of aphids that might be on a plant. Different kind of shortcut methodologies like that making it easier for decision makers to make a decision or shortening the amount of time it takes for decision maker to come to a decision, whether that decision is the treat or not treat or hey I need to come back in another week and sample more insects because I – there aren’t enough here to really make a concrete confident up or down decision on yet.

So yeah I think about all those things when I think about IPM adoption, but at the end of the day I’m really just thinking about how do we make the decision tools that we have available and the management tools that we have to available, After we make those decisions more convenient for people to use and sometimes it you know convenience is also a matter of crop value so whether that crop value is high or low your tolerance for spending more time scouting or using a given tool might change from year to year depending on that that market. So I think bringing all that together in in context is really what I think about about IPM adoption and then ultimately if we can have a suite, a strategy for IPM for a given pest and it’s reliably convenient to deploy for sampling has a robust solution of maybe multiple tools or tactics for management. So we’ve got different options for a manager to make a decision with then becomes part of the culture and becomes the way that you manage specific pest using various tools and tactics that you might use. And so then ultimately adoption is a matter of culture becomes part of the culture and practice of of how you deploy a pest management strategy against a given species.

12:19 E: So folks, today we started a new section of Farm Sci-Ed, where we talk about the science and education behind integrated pest management.

We started talking with Jeff about what the three pillars of pest management are and how they factor into integrated pest management. We also discussed how entomology and insect pest management gave way to the current integrated pest management practices. Join us next time as we talk to Nevin and Bob about their respective disciplines and what integrated pest management means to them. Find us on twitter @TheFarmSciEd

and on our website at farmsci-ed.com for transcripts and more details. Have a good one!

Entomology, Integrated Pest Management, Plant Pathology, Weed Science

Episode 12: August Field Update

Join Emily as she talks to Jeff, Nevin, and Bob about their research project updates.

Transcript has been edited slightly for clarity.

0:19 Emily: Hi everyone, and welcome to Farm Sci-Ed, the show where we go into the science and education behind farming. I’m Emily Stine and today we’ll be talking to Jeff, Nevin, and Bob about what’s been going on in their fields over the course of the last month of August. So sit back, relax, and let’s go find out what they’ve been up to.

0:36 So Jeff how has your research been going?

Jeff: Well, in August in our relay study, we’ve continued to sample all the plots with the exception of the wheat only plot, as the wheat’s gone. So our continuing sampling has been primarily in the bean only and a relay treatments.

And so with that, as I mentioned previously, we’ve had some some challenges with the study that are related to these being research plots and the challenges of shared equipment related to that and timing of everything. So timing in this relay system, particularly for herbicides is important. And that post post-harvest operation of the wheat in the relay system, it’s pretty critical to get that post herbicide application on, but we have to wait for the wheat to be harvested before we can get that application out there.

So that relates to our time in August because we can see in some of those relay plots, the the weed – the weed escapes as a result of us not being as timely as we would like to in these research plots anyway to get herbicides on. So other approaches we could have taken with the research was if we would have had smaller plots we could have used a sickle bar to cut the wheat and then maybe hand harvested the wheat but our plots are quite large – 40 by 40 feet – so that wasn’t really viable option for us um and we don’t have a 40-foot sickle bar so totally out of the question but because we were using a combine, trying to simulate that at least on a small scale. We were waiting for the equipment to become available, so we weren’t able to be as timely as we would like.

But we are continuing the sample as I mentioned earlier for for insects. We had one more sampling time of of different sample types and we talked about that before; sticky cards, vacuum samples, pitfall samples, we give those another opportunity for catch in August. And now we’re basically watching the beans turn yellow, so senescence – maturity of the beans seems to be a little earlier this year, and we can see that also in commercial fields in the area. Some of the beans that got in a little earlier, particularly around the hay springs area in Nebraska are already cutting and so our research plots are following suit. They’re turning yellow and it seems like the dry beans that are in the relay treatments – uh i think we observed this last year as well – are a little bit later in the maturity timing relative to the bean only.

So if you’re out looking at our plots, you’d see the bean only plots would be pretty yellow and the pods are starting to dry down, in our relay study you might even still find some flowers out there. So quite a bit of delay in the timing, and that’s related to shade and some other factors that will be one of the many things that we’ll have to tease out and work around because delayed maturity in beans is not a desirable trait to have in a cropping system, particularly for dry beans. You ideally want to get them harvested as early as you can, but just part of the research and why we’re looking at those things.

3:54 E: And Nevin, how about yours?

Nevin: Well, August is kind of – at least for dry edible bean research and weed science – August is probably our slow month. Which is, which is nice because it’s going to get real busy real quick.

um So all of our treatments have been put out now, we’re kind of slowing down on our assessments as well. And so we’re just really maintaining plots right now and just sort of making observations. So a couple things that are happening: the dried beans are starting to turn, so uh this time of year as we get close to harvest, they start to get yellow and it’s it’s actually pretty interesting. If you’ve got a field where you’re not having any sort of pest pressure or irregular watering or anything like that or everything’s uh pretty uniform as far as your inputs go, you can you can start to pick out differences in um soil uh texture because you’re gonna see certain parts of the field which maybe have a different uh coarser texture, more sandy, not as much water holding capacity, potentially those are gonna start turning yellow a little bit quicker and so we’re starting to see that. We’re starting to see these patterns in the field where some parts of the field are turning yellow, some parts aren’t but those do actually occasionally line up with with weed control treatments as well.

So we had a couple, we had one experiment this year where we were applying a bunch of different soybean herbicides that are not labeled in dry edible bean, but we’re trying to see if there’s potential to expand a soybean label and a soybean herbicide into dry edible beans. And we’re seeing some delayed maturity from some of those treatments now that delayed maturity likely is not going to result in the yield impact but we’re going to find out but some of the plots that are now quite yellow, right next to it, they’re they’re still in the midst of flowering. And so there’s, there’s pretty noticeable differences between some treatments and so that’s sort of, just what we’re seeing now, um we’re making notes of that,. But that’s going to get teased out when we go for for yield so we’ll know what the moisture content is of those beans and that’s going to give us a comparison of of what the maturity is at that time of the year.

5:54 E: And Bob, how about you?

Bob: Well, there hasn’t been a lot of disease from any anywhere in our in our plots. We did find a few lesions um periodically, but not enough to to uh need a application of the fungicides for for a grower.

But because of the studies that we are doing, we’re trying, we will go ahead and spray; either if it’s not this afternoon, then we’re going to spray tomorrow just to test the treatments that we said we were going to use. And then um just see what happens, even though the disease has not been um has been formed in our plots very readily. And but and I still don’t understand why, but it has not done that. But it is it – but it is present, I guess. and the spore catcher thing that we were trying to use – the spornado – has never told us that has – never detected any spores. So that would be with the disease triangle, that would be one of those uh points that were taken off. Which is then what we want to do to, to to manage that and they have not been conducive for the the disease to occur to a great extent. Although we have found a few here and there.

7:04 E: Well folks, there you have it. Today we talked to Jeff, Nevin, and Bob about where their research projects are at and what’s been going on in their fields over the month of August.

Stay tuned as we continue to delve into the science and education behind farming in plant pathology, entomology, and weed science. Follow us on Twitter @TheFarmSciEd and visit our website at farmsci-ed.com for transcripts and more updates. Have a good one!