Latest / The Illinois Nutrient Loss Reduction Podcast / Episode 27 | A Watershed Approach to Adopting Conservation
Transcript
- Episode 27 | A Watershed Approach to Adopting Conservation 00:00:05:28 - 00:00:34:28 Todd Gleason This is the Illinois Nutrient Loss Reduction Podcast, episode 27 A Watershed Approach to Adopting Conservation. I'm Illinois Extension Todd Gleason. You know, there are many reasons farmers across the nation are adopting cover crops like cereal rye. Chief among these are soil and nutrient conservation. Shalamar Armstrong has been researching the topic. He started at Illinois State University and then transitioned, he says, to Purdue University in Indiana. 00:00:35:00 - 00:01:00:07 Shalamar Armstrong Originally, I started my professor at Illinois State University in the Agriculture Department. I worked there for about four and a half to five years, then accepted a position at Purdue. But, Purdue was asking that I be, you know, a national, have a national program. And so I was able to keep my work that I started in Illinois and have been for the collaborations. 00:01:00:10 - 00:01:02:16 Todd Gleason What is your research focus area? 00:01:02:18 - 00:01:49:05 Shalamar Armstrong So my research, focuses on, conservation practices for both, for nutrients, water and soil, in-field practices primarily cover crops. And also, for nitrogen management. And looking at the impact of those practices, on, the agronomics, you know, the bottom line, of the producer of the farm, as far as yield, nutrient acquisition by the plants, you know, plant crop nutrition, soil health, soil nutrient cycling, and then when you couple all that, all of that together, you have to think about how, how is the the economics of that farmer impacted due to the inclusion or the, you 00:01:49:05 - 00:02:01:12 Shalamar Armstrong know, due to that farmer adopting, these in-field management practices. So we focus on, you know, from agronomic, economics to water quality, soil health. 00:02:01:14 - 00:02:03:26 Todd Gleason Because you're conducting this on a national level, 00:02:03:26 - 00:02:06:28 Todd Gleason are you still continuing your research in Illinois? 00:02:07:00 - 00:02:19:12 Shalamar Armstrong Certainly. I'm the lead on the project, in in the town of Lexington. We've been there for about, going on 7 or 8 years now. 00:02:19:14 - 00:02:50:21 Shalamar Armstrong What we're looking at four R nitrogen management practices, coupled with, the inclusion of cover crops. And we're looking at the impact of, of those practices on, the agronomic on, on economics, on the environment as far as water quality, air quality. We're looking at emissions of nitrogen to the atmosphere, greenhouse gases. And also, we're looking at we really, study the water quality. 00:02:50:21 - 00:03:26:21 Shalamar Armstrong The implications and ecosystem services of those practices. We've been doing that, for about 7 or 8 years. And then, I'm involved with one another, collaborate, on a watershed scale. So we learned on the field scale, and then we, you know, developed a watershed scale study soon after, in the town of Towanda in the Lake Bloomington watershed, where we've, located two large, well sub watersheds, in the Lake Bloomington watershed where we, we cover crop, half of the larger watershed. 00:03:26:23 - 00:03:49:07 Shalamar Armstrong And we did not cover crop the other watershed. And we're looking at the impacts of mass adoption we've come across that we have about 500 acres of public lands in that larger watershed. The watershed as a whole is about, 1100 acres. And so that's about half of that watershed that we cover cropping versus a 770 acre watershed where we well, we don't cover crop. 00:03:49:07 - 00:03:59:09 Shalamar Armstrong And we're looking at the water quality, because both of those watershed drains into Money Creek, which then goes to Lake Bloomington. It's almost as if you have a control. 00:03:59:09 - 00:04:02:19 Todd Gleason What's the difference between the two? Can you see results here? 00:04:02:26 - 00:04:22:10 Shalamar Armstrong Yeah. So, on a watershed scale. We are starting to see, results where we assume the cover crops are affecting, not so much the concentration of nitrate in the tile water or tile drainage water, but it's affecting the volume of water. 00:04:22:12 - 00:04:50:24 Shalamar Armstrong And so when you affect the volume of water and volume, multiplied by concentration gives you load. So we have a decrease load. And we didn't see that immediately. It took 2 or 3 years of cover cropping, for that system to mature and for those differences to, emerge. And so we're also seeing that, the average growth of cover crop is about, maybe 1,000 pounds per acre of biomass. 00:04:50:24 - 00:04:59:24 Shalamar Armstrong And in that thousand pounds, it's an average of 30 to 40, 30 to 50 pounds of, of nitrogen that's in that biomass. 00:04:59:27 - 00:05:21:15 Todd Gleason Because the concentration isn't different, is it that the biomass or the cover crop is holding water in the crop itself, or that the rooting system is allowing the soil to maintain a higher volume of water, or both, or something else? 00:05:21:17 - 00:05:44:28 Shalamar Armstrong It could be both. But primarily we think that, we hypothesize that the cover crop is, is growing. So therefore you have transit recreation occurring. And so it's using water. It's using water for, for its growth and for its growth. And so therefore while doing that is actually, it could be possibly drying out the soil. 00:05:45:01 - 00:06:06:28 Shalamar Armstrong Right. So, so you imagine if of soil, if this field does not have cover crops, it would take less rain to push water through the profile in order for it to be intercepted by the tile drainage, then goes to the creek. But but if you're growing a plant, you're growing plants longer. So, during more time throughout the season. 00:06:06:28 - 00:06:29:07 Shalamar Armstrong So in the fallow period, you're growing a plant when you normally would not. And so now you have this plant growing in this fallow period and it's using water. It's just causing the soil to be a little drier compared to where you don't have cover crops. And so it takes more rainfall, in order to create drainage. Right. 00:06:29:09 - 00:06:55:09 Shalamar Armstrong And so you have less of a volume of water leaving. And on top of that, now you still have the, the cover crops using or taking up nutrients, taking up nitrogen and holding it in as biomass, which is also, critical to nutrient loss reduction. Right. Because the within the biomass is not leaching and also is not denitrified to the atmosphere. 00:06:55:11 - 00:07:02:12 Shalamar Armstrong It's it's captured in the biomass to be released at some point later in time. 00:07:02:15 - 00:07:07:23 Todd Gleason Can you summarize the major takeaways you believe you have so far for producers? 00:07:07:28 - 00:07:21:20 Shalamar Armstrong Yeah. So on a on the field scale studies and at the, watersheds here, we see the same trend where you have cover crops, you are reducing nutrient loss reduction. 00:07:21:20 - 00:07:53:09 Shalamar Armstrong So you reducing the amount of nitrogen that leave in the field through the tile drainage. And we have seen reductions on the we can really be precise on the field scale. And so, 35 to 50% reduction in nitrogen loss okay. That's what we're seeing on the field scale. We can be precise there. On a watershed scale, you know, it's more difficult to come up with that precise number, but we think it's somewhere at least 30% reduction. 00:07:53:11 - 00:07:59:17 Shalamar Armstrong But it took it took time for the system to mature. After two years, we start seeing those reductions. 00:07:59:24 - 00:08:04:11 Todd Gleason What other questions about cover crops and nutrient management have you been researching? 00:08:04:11 - 00:08:15:14 Shalamar Armstrong We've been looking at the agronomic side of things. And so to be truthful, we we have not found all of the answers because we're studying the system. That's that's highly difficult. 00:08:15:16 - 00:08:42:05 Shalamar Armstrong We have cereal rye growing prior to corn. So those are two grasses, lot of antagonistic things that could occur. In fact, we recommend that you go cereal rye before soybean and some other species that cover crops like radish, oats, or clover before corn, however, cereal rye is the most common commonly used cover crop in in the region, of the Midwest and the Corn Belt. 00:08:42:07 - 00:09:06:09 Shalamar Armstrong And also it does the best job with nitrogen loss reduction, right. It keeps the nitrogen from being on the field. So, so my my group, my research group has taken on the task of trying to understand how to make it with feasible for farmers. And so we are actually, starting on a new answer, a new question that, you know, how to derive corn back to productive. 00:09:06:11 - 00:09:29:27 Shalamar Armstrong And so we're looking at what we call skid row technology. So when we drill the cover crop, the cereal rye prior to the corn, we, we drill in strips. We're leaving the space for the corn to grow, to be planted, where cereal rye was not planted. Right. So you're talking about non intersecting zones of growth of cereal rye and corn. 00:09:29:27 - 00:09:57:10 Shalamar Armstrong So we're using precision agriculture that normally is just used for corn and soybeans. But we're using that same precision, to plant the cereal rye. To leave a space with where the corn can be planted in the spring where cereal rye was not planted. And so we're doing that, and we're studying investigating that to determine if we are reducing some of this antagonistic, relationship between cereal and corn. 00:09:57:12 - 00:10:24:23 Shalamar Armstrong You know, by planting them in non intersecting zones across the field, we want to see, you know, can we get optimum yield doing that compared to the old way we planted which, which was broadcast or drilled. And that can be in a skid row. Do we have any negative trade offs with the environmental ecosystem services such as nitrogen loss reduction when we have this skid row technology? 00:10:24:26 - 00:10:50:02 Shalamar Armstrong Okay. And then, you know, could we use less seed and get the same environmental, ecosystem service and get equal or greater yield, which would be great. And so we in our first year of studying this, I have some colleagues in SIU, studying this, and we were working together across the entire state, to do this. 00:10:50:02 - 00:10:51:00 Shalamar Armstrong And also in Indiana. 00:10:51:04 - 00:10:55:23 Todd Gleason Any particular advice from you for producers when they want to try cover crops? 00:10:55:25 - 00:11:10:10 Shalamar Armstrong Yeah. So when you when you think about adopting cover crops, you need to first know, you know, what do you need in your field. You know what's. So we think about cover crops and all of that species, as tools in your toolbox. 00:11:10:13 - 00:11:33:04 Shalamar Armstrong You know what? What do you need? Erosion control. Because you have greater than 2% slope. Or do you have, you know, flatlands, you 2% slope and you have tile drainage and you want to reduce the nitrogen that’s leaving. So when you understand, the problem that you're trying to address, then you can select the proper cover crops. 00:11:33:04 - 00:12:00:15 Shalamar Armstrong And the other thought is this plan ahead. We recommend, you know, non grass cover crops before corn until we figure things out. Right. So if you're going to do if you're going into corn, you coming out of corn and going into something out of soybeans, going into corn. But you want to put something that's going to produce a low C/N ratio, carbon to nitrogen ratio of biomass, that releases the nitrogen quicker. 00:12:00:18 - 00:12:24:15 Shalamar Armstrong That's antagonistic to your corn, right. If you're going into soybeans, you can eat. There's no worries, you can use cereal rye. And so, think about your crop rotation. And you might want to rotate your cover crops with your cash crops and think about the problem that you're trying to solve. Think about cover crops as a tool in order to help you solve those problems. 00:12:24:17 - 00:12:52:10 Shalamar Armstrong And I think if you do that and plan, and, you know, tap into your resources, tap into your extension services, Midwest cover crop counsel, if you Google that, there's, there's, you know, decision making tools there to allow you to select and know when to plant and know, you know, the best timing to plant, and also know how to if you want to do a mix right, to get some diversity. 00:12:52:12 - 00:13:02:08 Shalamar Armstrong The tools there on that website will help you determine, the mixture, of that. The right the ratios can be to mix your current crop plant the species. 00:13:02:15 - 00:13:05:04 Todd Gleason Shalamar, it was great to talk with you. Thank you so much. 00:13:05:09 - 00:13:05:25 Shalamar Armstrong Thank you. 00:13:06:00 - 00:13:12:12 Todd Gleason Shalamar Armstrong is an assistant professor in the Department of Agronomy on the West Lafayette campus of Purdue University. 00:13:12:14 - 00:13:36:13 Todd Gleason You’ve been listening to episode 27 of the Illinois Nutrient Loss Reduction Podcast. The program is produced in conjunction with the Illinois Extension Watershed Outreach Associates. Jennifer Woodyard Jones and Haley Haverback Gruber. As described in the State of Illinois Nutrient Loss Reduction Strategy, Woodyard Jones works in phosphorus priority watersheds and Haverback Gruber's work is with nitrogen priority watersheds. 00:13:36:15 - 00:13:38:29 Todd Gleason I'm Illinois Extension's Todd Gleason.