2020 Cover Crop Conference Presentations

Deloris Pittman Author

02/28/2020 Added

36 Plays

Description

2020 Nebraska Cover Crop and Soil Health Conference presentation - Understanding Soil Health, Measuring Success and Reducing Risk - Aaron Hird, State Soil Health Specialist, Co-Presented with Noah Seim, Merrick County Farmer

Searchable Transcript

Search:

[00:00:21.420]So next I have Aaron Hird up.
[00:00:22.820]He's with USDA NRCS.
[00:00:24.960]He's the State Soil Health Specialist,
[00:00:27.410]and actually partners a lot with Nebraska Extension
[00:00:29.600]on programs across the state,
[00:00:31.500]and so appreciate having you here again
[00:00:34.190]and look forward to hearing from you, Aaron.
[00:00:35.740]Yeah, thanks a lot, Nathan.
[00:00:37.890]Really glad to be here, great turnout.
[00:00:39.850]Thanks for coming out.
[00:00:40.880]Thanks for inviting all of us to speak, Nathan and Keith,
[00:00:44.030]and all the information that we're able to share
[00:00:46.850]I think it's been a really great conference.
[00:00:49.280]Today, I wanted to take an opportunity
[00:00:51.750]to talk to you about my perspective on soil health,
[00:00:55.230]about some opportunities with NRCS and cost-share,
[00:00:58.390]and about some learning opportunities
[00:01:00.230]that we've kind of partnered on
[00:01:04.382]to facilitate spreading soil health
[00:01:07.360]across the state of Nebraska,
[00:01:09.140]and helping you have an opportunity
[00:01:10.440]to see it with your own eyes,
[00:01:11.970]kinda like Dean Krull said.
[00:01:13.230]He just needs to see it with his own eyes.
[00:01:15.473]So, at the end of this, I'm gonna talk about
[00:01:17.510]a partnership with Noah Seim,
[00:01:19.250]a producer there at St. Libory
[00:01:22.581]and about their demonstration farm.
[00:01:24.100]So, I'll go ahead and get started
[00:01:26.200]and get my part out of this done.
[00:01:28.360]That way we can talk more about that farming,
[00:01:30.500]that field that we're doing that demonstration on
[00:01:32.850]and take any questions we have about that.
[00:01:35.290]So, my name's Aaron Hird.
[00:01:37.310]I'm the State Soil Health Specialist with the NRCS,
[00:01:39.700]I work in Lincoln.
[00:01:41.070]I went to Chadron State College out in the Panhandle,
[00:01:43.490]and I worked for six years in New Mexico
[00:01:45.220]before coming back to Nebraska.
[00:01:47.410]So, I'm a range management specialist by training,
[00:01:50.600]and I look at this from a wildlife biology perspective.
[00:01:53.280]So, there,
[00:01:54.646]there's a whole can of different things and perspectives.
[00:01:57.840]But the take home is it's all ecological science.
[00:02:00.670]We're all just in an ecosystem,
[00:02:02.630]and everything needs food, water,
[00:02:04.650]air, space, and shelter to live,
[00:02:07.400]and everything wants to survive.
[00:02:10.200]And so it's an ecosystem
[00:02:12.050]and we're managing an ecosystem underground.
[00:02:14.670]And that's a perspective that I try and hold to.
[00:02:18.000]So I think understanding soil health and what it is
[00:02:20.580]helps us move forward in the conversation.
[00:02:23.580]We can measure success, and we can reduce risk.
[00:02:28.750]I think these pictures kind of captured,
[00:02:31.610]I tried to capture some of the things
[00:02:33.810]that I've experienced here through my career,
[00:02:36.920]working for the NRCS and extremes.
[00:02:39.280]I would call it extreme weather.
[00:02:41.330]I think 2019, two thirds of the state
[00:02:44.140]saw a flash flood event
[00:02:48.468]and not just the river systems
[00:02:50.110]that flooded and out of bank,
[00:02:51.370]all the flood plains, saw that destruction,
[00:02:54.070]but our uplands saw an enormous amount of destruction,
[00:02:57.010]erosion across that area of the state.
[00:02:59.570]And then the other third of the state got the blizzard.
[00:03:02.060]So they saw after that the melting event,
[00:03:04.920]and runoff, and flooding.
[00:03:06.750]So, 2019 was extreme.
[00:03:10.330]I captured some pictures from an opportunity
[00:03:12.920]I had in Thayer County in 2015.
[00:03:16.600]We had a 15 inch rain event in one night
[00:03:20.220]and that was extreme weather.
[00:03:23.020]A producer I worked with there said
[00:03:24.720]he thought he experienced 40 years of erosion in one night.
[00:03:29.800]I could relate, there were 20 foot wide,
[00:03:31.800]20 feet deep gullies there,
[00:03:34.030]that weren't there the day before.
[00:03:37.647]And we saw just enormous amounts of earth get moved,
[00:03:40.810]and trees, and bridges, and everything,
[00:03:43.000]it was a mess.
[00:03:44.630]I went around that morning, and captured a bunch of photos,
[00:03:48.350]and these photos capture some of the things that we saw
[00:03:53.332]that spring, it was May, right,
[00:03:55.340]May 8th, I think, we got that rain.
[00:03:57.980]And most of the corn was planted and up,
[00:04:01.521]and we saw some hill tops flood out,
[00:04:04.430]cause there was just so much water
[00:04:05.760]in places that we'd never seen water before.
[00:04:08.040]Some of these words sound familiar to 2019.
[00:04:10.990]There's water in places that
[00:04:12.090]we'd never seen water stand before,
[00:04:14.500]and the corn was drowning out on top of hills,
[00:04:19.380]where it was a 3% slope right there.
[00:04:21.560]It was just so much water in the profile,
[00:04:23.440]it couldn't stand it.
[00:04:25.240]And we saw gullies,
[00:04:26.630]this is on like a little 40 acre watershed,
[00:04:29.210]gullies coming down the hill,
[00:04:30.950]big thermal gullies, lots of erosion.
[00:04:34.800]But then I came across an opportunity
[00:04:36.550]to look at this field,
[00:04:38.220]and I was working with a producer,
[00:04:39.810]we'd planted a temporary grass waterway, I called it.
[00:04:43.250]We just used cover crops right there
[00:04:44.760]where the grass waterway used to be.
[00:04:47.710]He had just terminated that cover crop,
[00:04:49.830]right ahead of that event.
[00:04:52.030]And that drains two whole pivots,
[00:04:54.280]so about 260 acres comes through that waterway,
[00:04:57.240]and he gained soil right there.
[00:04:59.780]So that would normally be a really
[00:05:01.650]kind of a problem with the waterway,
[00:05:03.120]cause you'd have a lot of maintenance issues.
[00:05:05.470]That was temporary grass waterway,
[00:05:06.880]so he just seeded it down to a cover crop again,
[00:05:10.010]and went on, and herbicide treated it
[00:05:13.460]to kill that cover crop later.
[00:05:16.690]That same summer then I was on another hill top
[00:05:18.970]and saw droughting out corn,
[00:05:21.710]and I went, we just went from too much water
[00:05:23.810]to too little water, in the same season.
[00:05:28.210]I just started scratching my head.
[00:05:29.770]This extreme weather, what's going on with this?
[00:05:33.230]And then I was in this field,
[00:05:34.273]and this guy planted corn in the six foot tall cereal rye,
[00:05:37.830]which we told him not to do.
[00:05:40.919](audience laughing)
[00:05:43.762]But we told him, well if you're gonna do it,
[00:05:45.910]put on some starter fertilizer,
[00:05:47.700]cause that's what the best people that are doing this
[00:05:49.840]tell us to recommend,
[00:05:52.260]and that was the best yield he'd ever seen.
[00:05:54.550]Otoe County 2017, best yield he'd ever gotten
[00:05:57.940]off that dryland farm,
[00:05:59.780]and I just went, now that's extreme,
[00:06:02.070]but in a different way.
[00:06:04.190]And I started looking
[00:06:05.080]at some soil health assessments we're doing,
[00:06:08.290]and I was on a field,
[00:06:09.440]this is that cracked field right there.
[00:06:11.870]I was on this field in Knox County,
[00:06:13.940]and I measured an eight inch per hour
[00:06:15.960]infiltration rate,
[00:06:18.000]consistently across that field.
[00:06:20.560]It was cover crops, after a vetch crop,
[00:06:24.380]before a corn crop, he had a full season of cover crop,
[00:06:27.540]and he was grazing it.
[00:06:28.790]Sell grazing it, high intensity short duration,
[00:06:31.900]and there was earth worms as big as my thumb
[00:06:35.120]crawling around out there,
[00:06:37.490]they were size large earthworms.
[00:06:41.290]And I tell you what, the water,
[00:06:42.940]we could just pour buckets of water
[00:06:44.500]in every ring we put on that field.
[00:06:47.090]And I went, in 2015 I watched five three inch rain events
[00:06:52.300]come through like a freight train,
[00:06:53.690]through Thayer County,
[00:06:55.050]one right after the other, after the other.
[00:06:56.800]And that was only three inches per hour, over six hours.
[00:07:01.950]That was eight inches per hour, went in the ground,
[00:07:05.397]and I went that's a different extreme.
[00:07:08.240]That's extreme soil resilience,
[00:07:11.150]that's what we're all after.
[00:07:13.100]So I started to think,
[00:07:14.680]are we really seeing extreme weather?
[00:07:16.450]Or are we seeing an extreme reaction
[00:07:18.710]to the weather by our soil?
[00:07:22.059]And I went okay, now we can start
[00:07:24.550]to measure and quantify this.
[00:07:27.270]So I wanted to just lay out soil health,
[00:07:30.350]the definition of soil health,
[00:07:31.760]USDA NRCS has stepped out with this
[00:07:35.430]as our definition,
[00:07:36.800]and I think others have.
[00:07:38.520]The continued capacity of the soil to function
[00:07:40.600]as a vital and living ecosystem
[00:07:42.430]that sustains plants, animals, and humans.
[00:07:44.680]I underlined the most important part, for me,
[00:07:47.430]it's the continued capacity to function.
[00:07:51.410]So what does that mean?
[00:07:52.600]This morning you rolled out of bed,
[00:07:54.100]and you had the continued capacity to function.
[00:07:56.950]You had your own health.
[00:07:59.000]Your health is the same definition,
[00:08:01.570]and if you stayed out too late,
[00:08:04.120]your capacity to function this morning was diminished.
[00:08:07.700](audience laughing)
[00:08:11.020]If you treat your soil like junk,
[00:08:14.020]it's continued capacity to function is diminished.
[00:08:18.160]And so we really just have to manage
[00:08:20.410]the things that are living in our soil
[00:08:22.320]to provide for their capacity to live.
[00:08:25.400]And those five things about habitat,
[00:08:27.550]wildlife habitat management,
[00:08:29.250]food, water, air, space, and shelter.
[00:08:32.110]Space and shelter are the most critical aspects
[00:08:34.510]of the habitat in the soil.
[00:08:37.680]And I've got some pictures there
[00:08:38.600]of some habitat and space.
[00:08:41.920]I walk onto a field now, and I say is this soil healthy?
[00:08:45.540]I can kind of feel it in my feet,
[00:08:47.060]I can dig a hole real quick,
[00:08:48.540]and just identify some not identifiable characteristics,
[00:08:52.530]but I think it's important to understand
[00:08:54.290]the background of soil,
[00:08:55.497]and that not every soil is identical.
[00:08:58.640]Each field has it's own set of circumstances,
[00:09:01.520]because of the five soil forming factors.
[00:09:04.360]The idea that how long that soils been there,
[00:09:08.290]the flood planes that got flooded in '19,
[00:09:10.640]that's brand new soil that got laid down by those floods.
[00:09:14.120]It's only been there a season,
[00:09:15.910]it doesn't have very much soil structure,
[00:09:18.140]it doesn't have very much soil biology.
[00:09:20.640]It has a whole lot of organic matter,
[00:09:22.780]and it has a whole lot of food and water in it,
[00:09:25.610]and maybe even air,
[00:09:27.730]but it hasn't been there long enough
[00:09:29.130]to form aggregates,
[00:09:31.240]and so that matters.
[00:09:33.540]Aspect, the direction that a soil faces.
[00:09:36.670]I learned about aspect in New Mexico.
[00:09:39.920]The direction it faces, if it's facing north,
[00:09:43.100]that's some of New Mexico's most productive land,
[00:09:46.100]because it stays moist longer,
[00:09:47.770]it's cooler soil,
[00:09:48.775]and so the plants have an opportunity
[00:09:50.720]to grow with the resources they need.
[00:09:53.100]A south facing slope is almost a desert, guaranteed.
[00:09:56.900]In Eastern Nebraska here, that's not so important,
[00:09:59.760]because we get enough rain to counteract
[00:10:01.960]the temperature differences,
[00:10:03.530]and so really the south facing slope
[00:10:05.210]can be more productive here,
[00:10:06.480]because of the amount of precipitation
[00:10:09.700]overcomes the heat.
[00:10:12.120]So what it's made out of, parent material,
[00:10:14.370]really matters of course.
[00:10:15.790]We talked a lot about heavy clays,
[00:10:17.640]to silty clay loams, to sands,
[00:10:20.750]that really matters,
[00:10:22.030]and we can't change that very easily,
[00:10:23.860]or very cost effectively,
[00:10:25.500]so understanding what your soil texture is really matters.
[00:10:29.230]Climate, of course, Eastern Nebraska versus the Pan Handle,
[00:10:33.050]that's really gonna dictate
[00:10:34.290]the soil characteristics that we're talking about.
[00:10:37.800]And then the last one that I have on the list
[00:10:39.540]is biology.
[00:10:41.670]Biology, who manages the biology?
[00:10:44.660]Well, that's what we do.
[00:10:46.570]We put a corn crop out on that field for a season,
[00:10:49.920]and manage what is growing there,
[00:10:52.610]and what the corn crop associates with underground.
[00:10:55.920]That's our management.
[00:10:57.400]We're managing the plant, and the plant associates
[00:11:00.070]with certain organisms underground.
[00:11:03.110]Soil function, so those things that soil needs
[00:11:06.910]to continue to do, day in and day out.
[00:11:09.710]Every day we make assumptions
[00:11:11.690]about what the soil should do for us.
[00:11:14.550]Everyday we drive down the road,
[00:11:16.260]and we want that soil to stay stable,
[00:11:18.170]no big sink holes.
[00:11:20.650]That's a pretty common assumption,
[00:11:22.570]everyday I make it myself.
[00:11:24.710]How about when it rains,
[00:11:25.750]I expect the water to go in the ground.
[00:11:28.550]I expect it to hold that water and give it back to a plant,
[00:11:31.300]there's three more functions.
[00:11:33.570]How about nutrients?
[00:11:34.840]Let's apply it, take it in, hold it,
[00:11:36.780]and give it back to the plant,
[00:11:38.700]three more functions.
[00:11:41.110]I don't want the soil to be a disease,
[00:11:42.980]or harbor a disease, so,
[00:11:44.830]or be a pollutant,
[00:11:46.230]I'd like it to be a buffer and a filter,
[00:11:49.480]and I'd also like to to be a habitat.
[00:11:53.790]So, a habitat, that's an interesting term.
[00:11:59.100]Soil function is influenced by biology,
[00:12:01.180]which is impacted by management.
[00:12:03.150]That's what I spelled out here.
[00:12:04.440]90% of what we ask the soil to do
[00:12:07.170]is managed by what's living there,
[00:12:09.290]not by the soil itself, not by the dirt,
[00:12:11.960]but by the living biology.
[00:12:14.290]Supporting the biological activities
[00:12:15.950]can improve the soil functions.
[00:12:19.290]So I've been on hundreds of fields,
[00:12:21.130]all across Nebraska,
[00:12:23.340]and I've done the NRCS Nebraska Soil Health Protocol,
[00:12:26.850]we have a worksheet that we walk ourselves through
[00:12:29.070]on every field that we investigate.
[00:12:32.040]And the common problem in Nebraska that I've seen,
[00:12:34.530]that is the most limiting, on our sheet,
[00:12:38.477]is a tillage induced, root restrictive compaction layer.
[00:12:42.490]Well I still haven't been on a field
[00:12:44.360]that hasn't been tilled, 100% hasn't been tilled at all.
[00:12:49.260]I think I heard of one of those in Thayer County,
[00:12:51.420]where they just sprayed out rangeland
[00:12:52.840]and started planting,
[00:12:54.660]but that doesn't happen very often.
[00:12:57.180]So every time that we pull
[00:12:59.010]a piece of implement through the soil,
[00:13:02.570]it moves forward.
[00:13:04.480]And I grew up discing,
[00:13:06.170]I grew up on a farm in Central Nebraska,
[00:13:08.400]and I always think of discing
[00:13:10.290]as moving forward through the field.
[00:13:13.130]But I start to think about how much pressure
[00:13:16.300]that thing's putting down on the soil,
[00:13:19.405]and I looked up some numbers.
[00:13:20.290]A disc, just a standard tandem disc,
[00:13:23.560]it's about 250 pounds per disc blade, per square inch, psi.
[00:13:29.350]That's like two of me, standing on a one inch cube.
[00:13:33.540]I could shove that cube in the soil no problem.
[00:13:36.180]That's a lot of down pressure.
[00:13:38.260]And so the soil actually buckles underneath of that disc,
[00:13:42.000]it's like an accordion,
[00:13:43.500]and it rebounds some,
[00:13:45.060]but every time we put pressure on it,
[00:13:46.560]it destroys structure.
[00:13:49.170]And so we start thinking about discing and tillage
[00:13:52.070]as down pressure,
[00:13:53.640]then we start to understand where
[00:13:54.840]that compaction layer comes from,
[00:13:56.543]because it's compacting.
[00:13:59.160]And it compacts the layer right underneath of it,
[00:14:02.100]where that disc blade touches the soil.
[00:14:04.750]We've all dug holes in heavy played soil,
[00:14:07.630]and seen the smear on the side of the pit.
[00:14:10.990]That smear is what we leave horizontally
[00:14:12.990]through the field, with that piece of iron.
[00:14:15.210]And that leaves this layer right here
[00:14:18.510]at four inches, we have a lot of field cultivator
[00:14:23.520]compaction pans,
[00:14:25.140]some light tillage events occur at four inches.
[00:14:28.510]A lot at 6-8,
[00:14:30.010]every field that I've been in,
[00:14:31.340]I see a 6-8 inch compaction layer,
[00:14:34.300]and that's from discing.
[00:14:35.780]Sometimes it's flat,
[00:14:37.580]and sometimes it's in little ribbons, little waves.
[00:14:41.340]And I think those disc blades
[00:14:42.610]leave little waves across the field.
[00:14:46.380]I get a question almost every time I present this,
[00:14:48.680]can't I just deep grip it, and tear all that up,
[00:14:50.670]and flip it over?
[00:14:52.160]Yeah, those compacted aggregates stay compacted though,
[00:14:56.320]and the root still can't penetrate that soil,
[00:14:59.630]and it fractures it so they can get around it.
[00:15:02.290]And then we leave this compacted layer right down here,
[00:15:05.000]that looks like this,
[00:15:06.880]and I've seen those big waves underground,
[00:15:09.610]and the deeper we put that compaction,
[00:15:12.250]the less biology there is to address it at that depth.
[00:15:16.127]And so you're just moving your problem
[00:15:17.870]deeper, and deeper, and deeper in the soil.
[00:15:20.720]And the less root activity we see down there,
[00:15:22.730]the less earthworms,
[00:15:24.190]the less biological activity there is at depth,
[00:15:26.700]so it's really something to consider.
[00:15:30.030]In many soil types we have farmed the soils ability
[00:15:32.760]to withstand disturbance out of the top soil.
[00:15:35.480]I put that in because tillage works,
[00:15:39.310]tillage decreases bulk density,
[00:15:41.570]it increases infiltration rates,
[00:15:43.360]it cycles nutrients, it increases productivity,
[00:15:47.420]for one season.
[00:15:49.831]Then, after that season,
[00:15:52.010]it's settled back down, just like flour in a cup.
[00:15:55.240]If you tap that cup it settles back down
[00:15:57.450]tighter than it was when you started,
[00:16:00.360]and then it requires more tillage.
[00:16:02.690]And great-great-grandpa, or whoever broke your land out,
[00:16:06.440]had really healthy soil, it was black,
[00:16:09.030]it was prairie soils, it was highly aggregated,
[00:16:11.610]it had resilience.
[00:16:13.920]And when we tilled it, tillage worked,
[00:16:16.540]and the soil was resilient,
[00:16:18.120]so the aggregate stayed stable,
[00:16:20.050]and we had really high productivity.
[00:16:22.400]And for 100 years,
[00:16:23.520]or however long you've been farming your field,
[00:16:26.490]we've just continued with the same tillage event
[00:16:29.690]to create that productivity.
[00:16:31.710]And what we're mining is carbon,
[00:16:34.430]carbon leaves the system.
[00:16:36.230]And so we've come down to a very low amount
[00:16:39.040]of carbon in some of our fields.
[00:16:41.080]Just like Abby mentioned,
[00:16:42.280]one to half a percent organic matter
[00:16:44.960]in crop fields is not uncommon.
[00:16:47.010]That's really low.
[00:16:48.730]So that carbon is what makes soil resilient,
[00:16:52.410]that's where the aggregate stability comes from,
[00:16:54.300]that's the energy that's stored in the soil
[00:16:56.060]for the biological community,
[00:16:57.900]and the space and shelter that they need.
[00:17:01.250]So I looked at the root restrictive bulk densities,
[00:17:03.980]and I found a couple charts.
[00:17:06.280]This one on the right here, shows a standard field
[00:17:09.580]with some tire compaction and a disc plow pan, at depth.
[00:17:14.440]And a standard soil density in a crop field
[00:17:16.830]is supposed to be about 1.43,
[00:17:19.170]that's with a little bit of disturbance,
[00:17:20.690]and bare ground, and crop residues.
[00:17:23.970]Our engineering standard is 1.33,
[00:17:27.280]that's 50% air, and 50% soil.
[00:17:30.820]So 100% soil is 2.66 grams per cubic centimeter,
[00:17:35.840]that's if it was all soil and no air.
[00:17:38.740]So half of that is 1.33,
[00:17:41.310]so that's our engineering standard, that's normal.
[00:17:44.520]A field is 1.43, that's what the science tells us,
[00:17:49.170]and when I look at this chart,
[00:17:51.830]all these soil textures have different ideal bulk densities.
[00:17:55.430]That's because texture does matter,
[00:17:57.930]every texture indicates how hard it can compact,
[00:18:02.510]and how much space exists in that compacted area.
[00:18:05.310]And so ideally, in a silty clay loam,
[00:18:08.100]which I'm gonna stick with silty clay loam,
[00:18:09.650]cause that's what we've got here
[00:18:10.740]in Eastern Nebraska somewhat,
[00:18:13.270]less than 1.4 is ideal.
[00:18:15.610]Okay, so 1.43, that's not far off,
[00:18:19.010]and that's good.
[00:18:20.950]Well right here, at this eight inch,
[00:18:22.540]this one says seven inch compaction layer,
[00:18:24.660]that's the top of the plow pan.
[00:18:26.460]And a plow pan will exist in one inch layers
[00:18:28.820]if it's a really bad compaction layer.
[00:18:30.960]It comes apart in kind of pieces, one inch strips,
[00:18:34.970]and every strip has a different bulk density,
[00:18:37.150]just like this depicts.
[00:18:38.830]The top one, 1.9 grams per cubic centimeter.
[00:18:42.990]I've seen that, I've measured it,
[00:18:44.460]it's true, and 1.9 bulk densities
[00:18:48.420]that restrict root growth,
[00:18:51.250]1.9 stops roots in all soil types.
[00:18:55.470]And I think it's achievable
[00:18:56.780]and some of our worst compaction is in sands.
[00:19:00.090]That's where we can really achieve high densities,
[00:19:02.850]because it will compact and lock together.
[00:19:05.450]And so while sand seems like some of the lowest,
[00:19:09.040]it is some of the worst.
[00:19:12.390]And then every layer after that gets a little less dense,
[00:19:15.980]down to 1.78 at the bottom.
[00:19:18.270]That's just a two inch zone right there,
[00:19:21.600]that's super dense at eight inches.
[00:19:24.100]And that's what we're seeing in fields all across Nebraska.
[00:19:28.170]So how do we fix that?
[00:19:30.490]No tillage, we can stop recreating the problem yearly,
[00:19:35.567]no tillage.
[00:19:37.220]And then crop roots, yep they certainly
[00:19:39.780]address that compaction underneath the row,
[00:19:43.560]so we see a lot of root action underneath of there,
[00:19:45.660]and we begin to address that with no-till systems.
[00:19:48.640]Freeze-thaw, we can form some vertical structure
[00:19:51.900]with freeze and thaw events,
[00:19:53.500]but in a no-till field we're not freezing very often,
[00:19:56.180]one or two times a year, to eight inches.
[00:19:59.610]That's not very often, and that's not enough time
[00:20:01.780]for that vertical structure to form.
[00:20:04.160]And so that's why we're really looking at cover crops,
[00:20:07.550]you can have a higher rooting pressure tolerance,
[00:20:11.400]cover crop roots maybe aren't hybridized,
[00:20:14.170]maybe they're, they just are a different kind of plant.
[00:20:17.890]So tap rooted plants, like a grape seed, or a sun flower.
[00:20:23.550]Those tap roots have a lot higher
[00:20:25.380]rooting pressure tolerance.
[00:20:27.130]So that chart right here is for cash crops.
[00:20:30.780]Cover crop roots can withstand a lot higher pressures,
[00:20:33.570]so they'd blow right through that compaction layer,
[00:20:35.900]and we've seen it time, and time, and time again.
[00:20:38.460]So we can utilize the cover crop energy
[00:20:41.370]to blaze a trail through that compaction layer.
[00:20:46.240]Jay Fuhrer, I asked him a question,
[00:20:48.149]when can you see the first indication of success
[00:20:50.920]with a cover crop,
[00:20:52.060]he said year one, when a cash crop root
[00:20:54.490]follows a cover crop root channel.
[00:20:57.870]Always, you'll see a cash crop root
[00:20:59.520]go down that cover crop root channel,
[00:21:01.430]right through that compaction layer,
[00:21:02.970]because it wants to go there
[00:21:05.184]and access the soil profile.
[00:21:07.470]So we need to use biological activity
[00:21:09.530]to regenerate the soil structure.
[00:21:12.260]Everything that lives underground wants
[00:21:13.840]it's space and shelter,
[00:21:15.840]and everything, just like an earth worm,
[00:21:17.540]is gooey, it has an exudate,
[00:21:19.930]that soaks into the soil around it,
[00:21:22.210]and when it leaves, that exudate dries,
[00:21:24.810]just like Elmer's Glue,
[00:21:26.690]and it creates a little stable environment
[00:21:28.930]around that channel.
[00:21:30.580]Everything that lives underground has an exudate,
[00:21:33.580]and so it's all building stability
[00:21:35.940]within the soil profile,
[00:21:37.550]that's what creates aggregates, it glues itself together.
[00:21:41.410]And if we'd stop destroying that, annually with tillage,
[00:21:45.250]we can retain that benefit,
[00:21:47.230]and we can increase it.
[00:21:49.050]So we can accumulate it through time.
[00:21:53.200]This is an accumulation of benefits from Paul Jasa.
[00:21:55.830]Paul's sitting back here.
[00:21:58.070]We have a really great opportunity
[00:21:59.540]to partner with Paul, and all of UNL.
[00:22:02.570]We're doing a lot of research with them,
[00:22:04.560]and just walking through these trials.
[00:22:07.750]Thanks Paul for letting me borrow this slide,
[00:22:10.080]I put it together and got
[00:22:11.740]some pictures here to go with it.
[00:22:13.670]I think this is a really neat opportunity,
[00:22:15.920]this is one of the longest term tillage studies
[00:22:18.100]in Nebraska for sure,
[00:22:19.410]and probably in our region.
[00:22:21.450]If you've never been to Roger's Memorial Farm,
[00:22:23.540]try and get to his Field Day in the summer.
[00:22:25.850]It's a great opportunity to see this 40 year
[00:22:28.512]no-till versus tilled plot.
[00:22:32.210]He's got randomized replicated plots
[00:22:34.230]on top of a hill, it's 3-6% slopes,
[00:22:38.290]it's on an Aksarben soil,
[00:22:39.900]which is widespread in Eastern Nebraska,
[00:22:42.940]and so it's really a common experience,
[00:22:45.780]that you can share with Paul,
[00:22:47.160]and look at the results.
[00:22:49.690]So when I talk about bulk density and no-till,
[00:22:53.250]40 years of no-till on this field
[00:22:55.550]has resulted in this difference
[00:22:57.660]between this tilled plot and this no-till plot.
[00:23:01.750]When I say tilled, it's fall plowed,
[00:23:04.550]and spring double disced,
[00:23:07.270]every year,
[00:23:08.200]except for this year, because it was too wet.
[00:23:10.670]Paul said he didn't plow this last fall,
[00:23:13.470]and so he is trying to use good farming practices,
[00:23:16.740]he's not just in this for the science,
[00:23:18.760]he's trying to be a good farmer, using his plow.
[00:23:24.440]So it's pretty phenomenal that the bulk density
[00:23:27.760]has changed, separated itself that much.
[00:23:30.870]So that's more than 50% air in that no-till soil.
[00:23:35.010]Now we're below 1.33,
[00:23:38.650]so that's more space in the soil
[00:23:41.820]than there is soil itself,
[00:23:44.860]and at depth it's just as far of a separation.
[00:23:50.450]What that does is it increases the infiltration rate.
[00:23:53.780]For water to go in our soil,
[00:23:55.870]air has to come out.
[00:23:57.510]It's like a loan, we have to replace volume for volume,
[00:24:01.680]the air and the water.
[00:24:03.300]So saturated hydrologic conductivity,
[00:24:06.530]that's infiltration, while it's saturated,
[00:24:10.060]that's the slowest water moves in,
[00:24:11.830]after it's already all wet,
[00:24:14.650]and he has controlled traffic,
[00:24:16.770]Paul's got a great demonstration
[00:24:18.670]of a controlled traffic system there,
[00:24:20.210]so he's got tire tracks versus non-tire tracks.
[00:24:24.470]Less than 50% of the field sees a tire track,
[00:24:27.760]and in his wheel tracks,
[00:24:29.750]in the no-till it's 0.6 inches per hour.
[00:24:33.290]And in the tilled plot,
[00:24:35.980]in that wheel track, it's 0.2.
[00:24:38.600]Those are the measurements that I measure
[00:24:40.620]across Nebraska almost everywhere.
[00:24:43.280]A half an inch per hour infiltration rate,
[00:24:45.600]if that fields been tilled ever before.
[00:24:48.740]That's the condition that we're maintaining with no-till,
[00:24:54.230]but if we stop compacting it,
[00:24:57.820]with the controlled traffic system,
[00:24:59.690]just that change alone took it to four inches per hour
[00:25:03.250]compared to 0.4 inches per hour.
[00:25:06.790]And that's over 50% of the field,
[00:25:09.640]in a no-till system, without a tire track,
[00:25:12.200]has that much of an increase in infiltration rate.
[00:25:14.980]That's what I'm after,
[00:25:16.520]because if we can impact
[00:25:17.700]our infiltration rates in a watershed,
[00:25:20.180]there's less run off, there's less soil movement,
[00:25:22.610]there's less nutrient loss,
[00:25:24.090]and there's less flooding in that watershed.
[00:25:26.890]And when we talk about small watersheds,
[00:25:28.940]that you control,
[00:25:30.360]you can control the runoff from your field,
[00:25:32.840]but when we start accumulating that benefit
[00:25:34.720]across the larger watershed,
[00:25:36.860]say the Missouri River Watershed,
[00:25:39.330]we could really change our flood stage events
[00:25:41.490]with an increased infiltration rate.
[00:25:43.680]So as far as a regional, or worldwide impact,
[00:25:46.980]it's in our control.
[00:25:50.150]And then, I really like that these plots
[00:25:52.230]come with yield data,
[00:25:53.520]this is kind of an average that we just accumulated
[00:25:56.370]from the slide that Paul shared with us for efficiency.
[00:26:01.900]Corn, over those eight years, of the data that I saw,
[00:26:06.570]yielded 204 versus 184,
[00:26:09.280]and beans were 55 versus 51.
[00:26:13.620]That's an important fact,
[00:26:16.060]that it's still returning a good yield
[00:26:19.790]in a no-till system.
[00:26:23.160]This is what's actually happening
[00:26:26.070]on the soils surface.
[00:26:27.180]Now we have space, we don't have a crust,
[00:26:31.070]so when there's residue covering the soil surface,
[00:26:35.410]those pores can stay open.
[00:26:37.300]There's air, and water can replace it,
[00:26:40.330]and we can get infiltration,
[00:26:41.990]and roots can move through theses channels.
[00:26:44.830]But as soon as we have exposed soil,
[00:26:47.667]the soil aggregate stability goes to zero,
[00:26:52.070]and we get that crust formed.
[00:26:54.340]And when we form a crust, when it's raining,
[00:26:56.620]the water runs off,
[00:26:58.050]and that's what creates lateral movement of water.
[00:27:01.000]We stop infiltrating vertically,
[00:27:02.850]and we start moving laterally,
[00:27:04.700]and as soon as we do that,
[00:27:05.630]there's velocity that picks up soil and nutrients
[00:27:07.910]and carries it off the field,
[00:27:09.720]and that's where erosion occurs.
[00:27:13.000]So NRCS has developed these Soil Health Principles.
[00:27:17.955]We are promoting these four principles,
[00:27:21.140]minimize disturbance with no-till,
[00:27:23.110]we're really good at that in Nebraska.
[00:27:25.090]In 2017 over 52% of the harvested acres
[00:27:28.480]were under a no-till system.
[00:27:30.800]We're the number one state in the nation
[00:27:32.430]for no-till acres harvested.
[00:27:35.010]So that's a really big deal,
[00:27:36.520]because of some of the research we're showing
[00:27:38.320]when we add cover crops to no-till systems,
[00:27:41.530]maximizing soil cover with an active plant.
[00:27:44.930]We can increase that infiltration rate,
[00:27:47.670]we can maximize biodiversity,
[00:27:49.800]and more importantly, we can provide
[00:27:51.180]that living root to do that work underground.
[00:27:54.740]So, we do the soil health assessments across the state,
[00:27:58.760]I'm gonna skip through a couple of these
[00:28:00.860]and get to the Soil Health Initiative.
[00:28:03.070]We have demonstration farms across the state
[00:28:05.680]at 17 locations.
[00:28:07.470]Partnerships are our main focus,
[00:28:09.330]partnering with UNL extension,
[00:28:11.240]partnering with On-Farm Research Network,
[00:28:13.390]and UNL agronomy and horticulture, has been a big deal.
[00:28:18.810]These five year studies that were funded,
[00:28:21.510]starting in 2016, and '17, and '18,
[00:28:24.878]are on real fields, field-wide research,
[00:28:29.160]we're capturing the data with On-Farm Research Network,
[00:28:32.090]and we're using a lot of really neat tools
[00:28:34.440]to capture crop differences, and make comparisons.
[00:28:38.920]These 17 projects are looking at
[00:28:40.580]cover crops versus no cover crops in five of them,
[00:28:43.690]and all these other topic areas.
[00:28:47.040]Here's a map of all the farms across the state,
[00:28:50.280]we're hosting Field Days at each one of these farms.
[00:28:54.000]And specifically today I wanted to talk a little bit
[00:28:56.900]about Noah Seim's farm, there at St. Libory.
[00:28:59.960]There's a case study in your folder,
[00:29:02.600]this is brand new, hot off the press.
[00:29:05.250]This is the first time this has been released
[00:29:06.970]from On-Farm Research Network.
[00:29:09.100]It's the case study for the '19 results,
[00:29:11.560]2019 results from this farm,
[00:29:14.430]and the soybeans that we harvested there,
[00:29:17.990]or that Noah harvested there,
[00:29:20.550]and the cover crops he used.
[00:29:22.230]So in October I was able to go out and take
[00:29:24.380]soil health assessments in every plot.
[00:29:27.550]There's 18 plots on this field.
[00:29:29.960]We replicated the treatments six times,
[00:29:33.850]and there's a control, no cover crop.
[00:29:36.910]There's a strip that only sees cover crops after corn,
[00:29:40.860]or in corn, interseeded, right.
[00:29:42.860]No, dormant seeded.
[00:29:45.770]So there's a dormant seeded plot,
[00:29:47.260]and then there's a plot that sees dormant seeded
[00:29:49.350]plus interseeding, in the corn.
[00:29:52.030]So it's almost two cover crops in that one.
[00:29:55.380]And so as you look at this chart, and this case study,
[00:29:58.800]I didn't put this on the slide,
[00:30:02.090]you can see that we took baseline soil tests,
[00:30:04.610]with Haney tests, and standard soil samples.
[00:30:07.350]We're gonna follow-up with that
[00:30:08.710]in year three and year five,
[00:30:10.550]so that we get a trend of the soil test results,
[00:30:14.570]and that'll come out next year.
[00:30:16.490]On page two there
[00:30:17.890]we have some of the soil health measurements
[00:30:20.690]that we performed, or conducted.
[00:30:24.010]And it also shows the statistical analysis,
[00:30:26.700]and that's the wonderful thing about working
[00:30:28.280]with UNL Agronomy, and On-Farm Research Network,
[00:30:31.050]is all of this is statistically analyzed for confidence,
[00:30:36.060]and shows whether it's statistically valid
[00:30:38.180]or statistically the same.
[00:30:40.240]The differences are provided confidence that way,
[00:30:43.610]and it's peer reviewed,
[00:30:44.720]so we have a group of peers that looks at this
[00:30:47.190]and makes sure it makes sense,
[00:30:48.790]so that we're not just shouting in the wind.
[00:30:52.730]So when I look at the infiltration rates on this,
[00:30:56.410]while the p-value doesn't provide,
[00:30:58.580]that it say that it's confident,
[00:31:00.210]that there's any difference,
[00:31:02.070]anecdotally there's two inches difference
[00:31:04.310]between the check and the dormant plus interseeding,
[00:31:07.530]and when we come across here,
[00:31:08.930]soil respiration showed to be statistically significant,
[00:31:13.513]and then table two, there's the management,
[00:31:16.270]the, let me look across here,
[00:31:19.290]thought there was another one.
[00:31:22.480]Nope, just the field management of course.
[00:31:26.079]So what I point out then,
[00:31:29.247]is, we go down to the margin, and that return on the yield,
[00:31:31.970]on the bottom, table three there.
[00:31:35.671]And for two years running,
[00:31:36.830]you'll see on page three,
[00:31:38.210]there's last years results from the corn,
[00:31:41.150]and for the two years that we've captured results
[00:31:44.250]the dormant plus interseeded strip
[00:31:46.560]has out yielded the other strips,
[00:31:49.430]and I think it's two bushels more
[00:31:53.380]than the dormant seeded,
[00:31:54.607]and two or three bushels more than the check strip.
[00:31:58.410]And that's playing out, and accumulating through time.
[00:32:02.050]Noah was pointing out that this field
[00:32:03.580]has a really poor history,
[00:32:06.079]it's really sandy, and it was full with tillage
[00:32:09.780]for a number of years,
[00:32:11.570]and it's really really low organic matter.
[00:32:14.120]So we're starting with basically a sand box,
[00:32:16.840]and we're moving forward from there,
[00:32:18.660]so the rate of change is gonna be slow,
[00:32:21.920]and accumulate through time.
[00:32:23.460]That's where these five year studies really come in handy,
[00:32:26.170]cause we're gonna watch the system
[00:32:27.920]through the whole amount of time.
[00:32:29.930]So Noah, I think you have a mic on,
[00:32:33.970]is there anything that stood out to you
[00:32:35.540]from your experience with On-Farm Research,
[00:32:38.560]your experience with this trial,
[00:32:39.970]or from 2019?
[00:32:42.910]You know, probably the biggest thing
[00:32:45.439]is just getting some data that's quantifiable
[00:32:49.860]to what we've been doing.
[00:32:50.900]You know Dean was up here before,
[00:32:53.080]and showed you guys some of those pictures.
[00:32:54.840]I was sitting in the back,
[00:32:55.790]that was my family that put together that redneck machine
[00:32:59.470]that had the insecticide boxes on it,
[00:33:02.567]and the rotary hose that you guys all laughed at.
[00:33:05.260]So, you know, that was some of the stuff
[00:33:06.530]that we started with,
[00:33:09.521]and where we started and had questions.
[00:33:12.060]You know, none of us have the education background
[00:33:15.280]that Aaron, or some of these other speakers have had.
[00:33:17.260]So we're seeing stuff change in our fields,
[00:33:19.450]but we wanted to be able to put some proof behind it,
[00:33:23.900]and so being part of the On-Farm Research
[00:33:26.560]has provided that,
[00:33:28.700]to bring in the University,
[00:33:30.050]to work with Aaron and the NRCS,
[00:33:32.890]to say that we can put stuff on paper that,
[00:33:35.370]yeah we see it in the field,
[00:33:36.470]changing and improving, but there's evidence
[00:33:38.840]that shows that it is improving also.
[00:33:41.490]Yeah, and like Aaron said,
[00:33:42.840]we started with, this farms got about
[00:33:45.400]25 foot elevation changes on it,
[00:33:47.650]which isn't much, right, for you guys out here,
[00:33:49.790]but for us, most of our ground's table top flat.
[00:33:52.770]But Valentine Thurman sand,
[00:33:55.740]a little bit of Kennesaw silt loam,
[00:33:57.530]and like I said, I mean, chisel plowed,
[00:34:00.880]disced, you know, full tillage.
[00:34:04.340]We started farming it six years ago,
[00:34:07.420]so, you know,
[00:34:09.330]I'm trying to change a lot of things out there.
[00:34:11.050]The biggest things we've seen
[00:34:13.023]is erosion control's been huge,
[00:34:14.700]just from doing the cover crops.
[00:34:17.480]Wind erosion you mentioned.
[00:34:19.080]Yeah, wind erosion, even water erosion,
[00:34:21.340]but wind erosion, you know, when it was full tillage
[00:34:23.574]by the previous owners,
[00:34:26.970]it was nothing to see a third of it just get
[00:34:29.380]mowed off by the sand blowing out there.
[00:34:31.860]So the wind erosion, soil erosion,
[00:34:33.630]because of the slopes that we do have out there, so.
[00:34:37.930]You know, we've got some other stuff
[00:34:39.410]we do some cover cropping on,
[00:34:41.537]and a lot of our stuff that we've seen
[00:34:43.320]great results with has been water infiltration,
[00:34:47.230]those kind of things, so
[00:34:48.610]weed suppression's been huge,
[00:34:49.960]like a lot of these guys have talked about.
[00:34:52.550]It doesn't take, it doesn't really take that much
[00:34:55.050]of an amount of pounds of product
[00:34:58.736]to get a result, when it comes to any of those things.
[00:35:01.960]Yeah, so rates, cover crop rates,
[00:35:05.276]have been a learning curve for you.
[00:35:07.640]Yeah, we've done some stuff,
[00:35:09.960]Dad's got a mix, he was being cheap,
[00:35:12.110]it's six pounds of cereal rye and four pounds of red clover
[00:35:14.800]that we've interseeded every year
[00:35:16.300]since we started doing this.
[00:35:18.090]And most of you guys that do cover crops pretty intensely
[00:35:21.640]are probably laughing at that,
[00:35:22.820]because it doesn't sound like anything,
[00:35:24.380]but we've seen it be enough to increase
[00:35:27.980]our infiltration rates,
[00:35:29.210]and we've seen it be enough to suppress the weeds.
[00:35:32.100]Especially, you know, you guys saw some of the pictures,
[00:35:34.010]the interseeders, you come out to a pivot arc,
[00:35:36.040]like you can see on the left hand photo there.
[00:35:38.170]You've always got that piece of pie where
[00:35:39.510]you picked your implement up, turn it around.
[00:35:41.610]If you go on through the field harvesting,
[00:35:42.990]and not have a single week,
[00:35:44.050]and you come on to that little piece of pie right there,
[00:35:45.960]at the edge of the field on that arc,
[00:35:47.860]and where there weren't any cover crops planted
[00:35:50.510]it'll be full of weeds.
[00:35:52.020]So, you know, we're seeing those benefits
[00:35:54.630]here and there, all over the place.
[00:35:56.870]Yeah, so the opportunity to work
[00:35:58.310]with On-Farm Research Network
[00:35:59.930]has been really huge,
[00:36:01.000]working with their extension agent Dean Krull,
[00:36:03.130]has been a huge opportunity,
[00:36:05.240]just data collection and continuity of service,
[00:36:08.310]and then just learning together,
[00:36:10.210]has been a key.
[00:36:11.043]Yeah, that's been the biggest thing
[00:36:11.876]is just sharing the knowledge,
[00:36:13.040]and obviously coming to events like this.
[00:36:16.087]The contacts, you know,
[00:36:17.760]somebody had a slide up there before
[00:36:19.130]about the networking of somebody talking to you,
[00:36:22.070]or talking to somebody else,
[00:36:23.790]and just how that spider webs out.
[00:36:25.610]So I'd like to leave with this,
[00:36:29.510]On-Farm Research Network is hosting
[00:36:31.950]their annual results update meetings
[00:36:34.270]here at the end of February,
[00:36:36.180]and they're all across the state.
[00:36:37.610]There's one right here,
[00:36:39.120]do you know what date that is here?
[00:36:41.189]I can't remember.
[00:36:42.627]Thursday?
[00:36:43.460]Is it Thursday?
[00:36:44.293]No Tuesday, Wednesday night.
[00:36:45.860]Wednesday next week.
[00:36:46.693]Yep.
[00:36:47.526]Those results update meetings are real research
[00:36:51.510]done on real farms, with farmers,
[00:36:54.050]and the farmers usually present their material,
[00:36:56.400]and then there's a group discussion and questions,
[00:36:58.880]and then the next study, and the next study,
[00:37:00.618]it just goes on and on.
[00:37:02.690]It's such really intriguing information.
[00:37:06.200]This year on February 28th we're gonna host
[00:37:08.670]a soil health-centric On-Farm Results Update meeting,
[00:37:13.370]in York, and so all the cover crop studies
[00:37:16.230]and any soil health-centric topic area
[00:37:19.870]is gonna get covered at that one,
[00:37:21.930]and we're gonna co-host that,
[00:37:23.390]and showcase some of these demonstration farms,
[00:37:25.700]that the NRCS helped provide,
[00:37:27.770]as well as the studies that
[00:37:29.380]On-Farm Research Network hosted too, so.
[00:37:33.400]On CropWatch is a really great place
[00:37:36.000]to find all of this information,
[00:37:37.790]not only On-Farm Research Network, but
[00:37:39.666]the Soil Health Initiative,
[00:37:42.010]and our case studies are found there.
[00:37:43.740]And so, with that, I would leave you with this,
[00:37:46.740]how can you help improve Nebraska's soil health?
[00:37:49.970]Dig a hole, learn a lot,
[00:37:52.980]and find your compaction layer.
[00:37:56.370]There's my contact information,
[00:37:57.940]thanks a lot.
[00:37:58.773]Yep, thanks Noah and Aaron,
[00:38:00.590]give them a round of applause.
[00:38:01.866](audience clapping)

The screen size you are trying to search captions on is too small!

You can always jump over to MediaHub and check it out there.

Comments

0 Comments

2020 Cover Crop Conference Presentations

Description

Searchable Transcript

Comments icon comment

Related Channels

Comments