Managing Manure to Help Reduce Nitrogen Management Issues
In this episode of the Nebraska Cropwatch Podcast Michael and Rick Koelsch talk about using manure as part of a farmer’s fertility plan. Can manure be used to solve water quality problems? Click play and find out the answer to this question and more.
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[00:00:02.920]Welcome to Crop Watch podcast,
[00:00:05.050]a production of Nebraska Extension.
[00:00:13.130]Welcome to the crop watch podcast.
[00:00:14.880]I'm Michael Sindler
[00:00:15.720]a crop insistence extension educator.
[00:00:18.040]Today, I'm going to be talking about manure.
[00:00:21.000]Specifically how do we manage manure when we're talking
[00:00:26.240]Nitrogen management's important, manure's important,
[00:00:28.350]and they both can work together.
[00:00:30.540]I'm going to be joined today by Dr. Rick Kelsh
[00:00:33.810]from the Biological Engineering school.
[00:00:37.300]Rick, how are you doing today?
[00:00:39.160]Doing well here Mike.
[00:00:41.740]Hey, thanks for the opportunity to talk a little crap today,
[00:00:47.230]Oh, well, you know it's a subject that you have
[00:00:49.620]to have a little fun with.
[00:00:53.730]There's a lot of jokes we could throw in here,
[00:00:55.470]but we'll keep it clean here.
[00:00:59.595]You know, first off there is nitrogen in manure,
[00:01:04.270]what forms does that nitrogen take?
[00:01:08.750]And that's really a great place to start
[00:01:10.720]when we're thinking about manure is you have to be aware
[00:01:13.550]that there's a part of the nitrogen that is in
[00:01:16.660]an organic nitrogen form, which is pretty different
[00:01:20.570]from what we manage with our commercial fertilizers.
[00:01:23.220]And then there's also a part that's in a ammonium form
[00:01:26.520]which is very much like the nitrogen in our
[00:01:32.020]So recognizing what your, do you have a lot of
[00:01:39.429]Do you have a lot of ammonium nitrogen is important.
[00:01:42.040]For example, our swine manure is probably gonna be 70, 80
[00:01:47.620]90% ammonium nitrogen.
[00:01:49.360]So it's going to behave a lot like
[00:01:51.650]our commercial fertilizers
[00:01:53.870]where our dry manures like our feedlot manure
[00:01:57.630]is probably gonna be 80 90% organic nitrogen
[00:02:02.270]and that's going to behave quite a bit differently
[00:02:05.040]than some of our commercial fertilizers.
[00:02:08.500]So you mentioned the different forms.
[00:02:10.200]How do we know how much nitrogen we have
[00:02:12.882]and, you know when we're looking at this can it tell us
[00:02:15.220]how much of the two different forms of nitrogen
[00:02:17.720]or does it just give us total nitrogen?
[00:02:20.120]Good question there.
[00:02:23.810]There are rules of thumb out there,
[00:02:26.260]but the best way is just to get a manure analysis done.
[00:02:30.450]And the labs that do our soil analysis will generally
[00:02:35.050]do manure analysis.
[00:02:36.350]So just get a good representative sample of the product
[00:02:39.950]that you create, or you're going to be laying applying
[00:02:43.280]and ask for a manure analysis.
[00:02:45.750]And yes, they do differentiate
[00:02:48.160]between the ammonium fraction, the organic fraction
[00:02:52.060]and the nitrate fraction.
[00:02:53.530]But typically it's almost all in the organic
[00:02:56.030]and the ammonium fractions.
[00:02:59.570]So when we were looking at applying nitrogen
[00:03:02.890]I'm guessing it's very important to add all three of those
[00:03:05.610]up when we're looking at how much we want to apply?
[00:03:10.060]It is at least the ammonia and the organic
[00:03:14.803]The ammonium fraction and its availability
[00:03:19.730]is really determined by how quickly we get that incorporated
[00:03:24.350]into the soil.
[00:03:26.310]So if we directly inject something like swine manure,
[00:03:32.300]almost all of that ammonium fraction is going
[00:03:34.450]to be available.
[00:03:35.283]We probably assume 95 to 100%.
[00:03:38.220]If we were to leave it on the surface
[00:03:40.940]and not come back until maybe 24 hours later in disc it in
[00:03:46.591]And well, it may be more down in that 50% of the range
[00:03:49.270]that that ammonium is available.
[00:03:51.510]So the time between when you apply it and when it gets mixed
[00:03:56.850]into the soil is very critical on the ammonia side.
[00:04:02.400]On the organics side, it's a little bit more dependent
[00:04:07.620]upon the type of manure that we're dealing with.
[00:04:11.400]Historically we've said let's say something like
[00:04:16.600]our feedlot manure about 25% of that is available to us
[00:04:22.430]the first year.
[00:04:24.200]So if I've got 20 tons or 20 pounds of organic nitrogen
[00:04:28.030]per ton, I'd probably only credit about five pounds
[00:04:32.550]in this coming year.
[00:04:35.180]Some of our manures or our poultry manure as an example
[00:04:38.910]can have higher fractions available
[00:04:43.020]from that organic nitrogen.
[00:04:44.860]So knowing the type of the manure is probably
[00:04:48.510]the most important factor on that site.
[00:04:52.120]So, you know those are good points
[00:04:54.870]with the type.
[00:04:56.240]You kind of briefly touched on application
[00:04:58.810]kind of application methods.
[00:05:01.910]When's the best time to actually apply manure.
[00:05:04.670]Okay, in terms of manures that are high
[00:05:09.580]in the ammonia fraction,
[00:05:10.800]I followed the same rules I would use
[00:05:12.960]for commercial fertilizer.
[00:05:15.510]You know, typically we'd like to see those soils
[00:05:18.110]below 50 degrees here in the fall.
[00:05:20.500]If we're going to apply the ammonium fraction to keep that
[00:05:24.160]ammonium from converting over into a nitrate form that could
[00:05:27.650]leach on us next spring.
[00:05:30.320]We probably have a little more flexibility
[00:05:32.960]with the manures that are higher in organic nitrogen.
[00:05:38.760]That conversion of organic nitrogen into eventually ammonium
[00:05:42.690]and then available to the crop is nitrate.
[00:05:45.690]Most of that's not going to occur now until next June,
[00:05:49.830]July, August when our swells are nice and warm.
[00:05:53.150]So I probably got a broader window I can apply manure
[00:05:58.000]that is high on organic nitrogen throughout much of the fall
[00:06:02.318]and expect to have most of that aVailable next spring,
[00:06:06.620]next summer when it's that crop is needing it.
[00:06:10.700]So you're talking about the different kinds
[00:06:14.320]When you look across the state of Nebraska, what are sources
[00:06:17.940]of manure that are fairly common that we can use?
[00:06:22.970]Through almost all of Nebraska, we will have
[00:06:27.030]feedlots out there that are harvesting form of manure
[00:06:32.100]that's going to be high in organic nitrogen.
[00:06:34.610]So that's, you'll see across the country, across the state.
[00:06:40.730]We've seen the development of the poultry industry here
[00:06:43.750]in Eastern Nebraska.
[00:06:45.600]It's good source of nitrogen.
[00:06:47.190]The poultry litter generally is in the range
[00:06:49.260]of 60 plus pounds of nitrogen, mostly two thirds
[00:06:54.510]three quarters in an organic form.
[00:06:57.320]And we've got quite a number of swine operations
[00:06:59.550]kind of different locations around the state to that
[00:07:04.870]it's that swine manure that's coming from below our barns.
[00:07:10.010]It's probably going to be almost all ammonium
[00:07:12.230]or at least 80 to 90%.
[00:07:16.020]So then when we look at how to apply,
[00:07:18.400]'cause you you talked how it's important, like how to
[00:07:20.760]apply it or steps to do right after that.
[00:07:24.090]When you look at different sources
[00:07:25.870]what are the important steps?
[00:07:27.220]For example you said if we're putting on liquid sign
[00:07:30.880]machinery we can lose up to 50% of our ammonia if we don't
[00:07:34.520]incorporate it within 24 hours.
[00:07:36.700]Are there other tidbits or tips like that for some of the
[00:07:44.420]Any manure that's going to be high in ammonium.
[00:07:46.870]Let's get, try to get that injected into the soil
[00:07:50.580]or if it's coming through a pivot like, from a lagoon
[00:07:55.730]or a holding pond that the water that comes with is probably
[00:07:59.620]going to incorporate it in the soil.
[00:08:01.810]Our ammonia losses would be pretty small.
[00:08:04.860]For organic nitrogen we're probably going to get roughly
[00:08:10.180]the same value out of that nitrogen, whether we lay it
[00:08:13.470]on the surface and just leave it on the surface
[00:08:15.640]or whether we incorporate it in.
[00:08:17.410]So it's not necessary to incorporate manure as high
[00:08:21.340]in organic nitrogen.
[00:08:24.350]We'll still see that same availability from that
[00:08:27.500]organic nitrogen whether it's laid on the surface or not.
[00:08:32.710]So I'm guessing for those that are really
[00:08:35.340]into the no till and don't want to till no matter what
[00:08:38.760]those dry sources that are high in organic carbon
[00:08:41.060]are probably the sources they want to look for.
[00:08:43.790]Yes, you're right.
[00:08:44.957]That's exactly what I would recommend.
[00:08:48.370]So you briefly touched on like
[00:08:55.000]Is there a role for an earner to play
[00:08:56.920]into the people's fertilization or nutrient plans
[00:09:01.380]And is that adjustment or only
[00:09:02.990]or is that complementing commercial fertilizer?
[00:09:06.897]Yeah, that's a good question.
[00:09:11.915]And you know, that the research has shown
[00:09:14.330]when you can design a fertility program where that manure
[00:09:17.700]and fertilizer are both complimenting each other
[00:09:23.960]both being used.
[00:09:25.210]That's probably some of the times where we get our best
[00:09:28.120]yield book that results from manure
[00:09:31.160]and especially true for those manures that are high
[00:09:34.460]on the organic nitrogen.
[00:09:36.590]The swine manure is I've already said
[00:09:38.170]it's going to behave very much like commercial fertilizer
[00:09:40.580]but our organic nitrogen pool from let's say
[00:09:45.410]our feedlot manure, it's not going to become really
[00:09:48.840]available to that crop until that snow warms up next summer.
[00:09:52.210]So we're talking June, July, August when that nitrogen
[00:09:56.450]really kicks in from that.
[00:09:58.780]So oftentimes we're going to need some complimentary source
[00:10:03.200]of nitrogen in the spring as that plant, that corn plants
[00:10:09.420]Our agronomist will recommend that we want to always include
[00:10:14.860]at least 60 pounds of ammonia nitrogen in a
[00:10:20.370]And if you're applying strictly beef manure
[00:10:22.570]then that means I probably ought to come in with some
[00:10:25.040]anhydrous, ammonia or urea
[00:10:26.520]or something like that to provide that.
[00:10:29.770]If I'm putting on the slime manure, well then there's plenty
[00:10:32.260]of ammonia nitrogen there and I don't need to compliment it.
[00:10:35.160]But our dry manures yes.
[00:10:37.040]Let's add in some commercial fertilizer, pre-plant
[00:10:41.800]planning time in that 60 pound range.
[00:10:45.950]So as a concern across a lot of the state
[00:10:49.110]with nitrate levels and groundwater is manure a possible
[00:10:53.630]strategy to help reduce nitrogen loss into ground water
[00:10:57.740]as putting that into our fertility plans?
[00:11:00.422]Mike, I'm glad you brought up that question
[00:11:03.083]because that's something I think there's a lot
[00:11:06.300]of misunderstanding on.
[00:11:08.100]I think we've historically viewed manure as being
[00:11:10.920]a water quality risk.
[00:11:13.910]And I think that mindset comes from the days when we applied
[00:11:18.570]manure really as a waste product, just to get rid of.
[00:11:22.690]And so we all over applied the nitrogen.
[00:11:25.560]And in those situations where manure nitrogen
[00:11:29.150]is over applied we're going to leach nitrogen
[00:11:32.983]No doubt about it.
[00:11:35.430]But boy, in today's world if you're staying in compliance
[00:11:39.700]with the regulations and you're an animal feeding operation
[00:11:42.700]that has a permit you have to credit manure nitrogen
[00:11:47.970]in your your fertility plan.
[00:11:50.040]And if it's done properly actually manure have some real
[00:11:54.230]advantages over our commercial fertilizers.
[00:11:57.640]That organic nitrogen in manure is kind of mother nature's
[00:12:02.530]low release nitrogen.
[00:12:04.540]And with our commercial fertilizers, some of us are spending
[00:12:07.090]money on buying slow release products to supplement
[00:12:11.590]our ammonia fertilizers.
[00:12:13.150]So yeah, organic nitrogen if we apply it at the right rate
[00:12:21.680]at an agrOnomic rate, it's going to become available
[00:12:25.840]in the next June, July, August, when that crop needs it.
[00:12:29.220]And it will have the least amount of risk for ever leaching
[00:12:34.200]But it all depends on are we going to apply it
[00:12:36.240]at the right rate?
[00:12:39.173]So where would we maybe find some of those resources
[00:12:41.880]on how to apply it at the right rate
[00:12:44.680]or where can we find more information on what
[00:12:47.220]you're working on?
[00:12:51.020]As a general rule, I would point people
[00:12:53.490]to a website and we regularly write on this topic
[00:12:58.140]and you can search past articles and find this.
[00:13:00.760]The website for our extension programs dealing with
[00:13:04.960]manure management is manure.unl.edu
[00:13:12.870]and then just do a search on nitrogen availability
[00:13:16.240]or whatever the manure related topic you'd be interested in.
[00:13:24.433]Well, thank you for joining us, Rick.
[00:13:26.150]You have a good one.
[00:13:27.570]Well, I enjoyed visiting a little bit
[00:13:30.100]about crap today.
[00:13:31.780]That's my life, I guess.
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