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In-Furrow Placement of Urea Products with Wheat Seed
Its that time of year I always get the question of “How much urea can I put in the furrow?”. My answer is always two fold first, I wouldn’t recommend it, its a risky venture. Even though I know some do it. Second, my research shows very little is any value from N in furrow. I like P but N just doesn’t show me any return. So for me the process is high risk, with little or no potential for return. But with blog I turn to our purple friend up north to share what their research has sown.
Brian
Guest Authors Kansas State University
Lucas Haag, Agronomist-in-Charge, Southwest Research-Extension Center, Tribune lhaag@ksu.edu
Alan Schlegel, retired
Dorivar Ruiz Diaz, Nutrient Management Specialist ruizdiaz@ksu.edu
To save time and cost, some wheat producers may be thinking about adding a little extra nitrogen (N) as urea or UAN to their phosphorus fertilizer through the drill with the seed. This would either be in addition to, or instead of, any preplant N applications.
While a minimum preplant N application of 20 to 40 lbs N per acre is often desirable, especially in no till production systems, there are risk involved when placing urea containing fertilizers in direct seed contact. Traditionally, we have suggested that no urea or UAN solution be placed in contact with the seed. With the continued adoption of air-seeders a common question we receive from producers is can urea, or enhanced urea products be placed in-furrow.
Methods of early-season nitrogen applications
If the starter fertilizer can’t be “spiked” with urea to add extra N, how can the necessary 20 to 40 pounds of N be applied? Subsurface banding (knifing) of N as either anhydrous ammonia, liquid UAN, or dry product will result in the greatest N use efficiency by the wheat crop. This is especially true for no-till wheat production.
If knifed N applications are not used, the next best application method would be surface banding (dribbling) of UAN solution in streams on 15- to 18-inch centers. Broadcasting urea, ammonium nitrate, or UAN applications are not generally as efficient as subsurface banding, but they are often the best choice due to equipment, logistics, or weed management considerations. Broadcast applications of N will have the most consistent performance if followed by light incorporation, precipitation, or irrigation.
Direct seed placement of nitrogen
When placing starter fertilizer in direct contact with wheat seed, producers should use the following guidelines:
The problem with placing urea-containing fertilizer with the seed is that urea is initially converted to ammonia and may be toxic to plant roots if the wheat seed is placed in direct contact with the fertilizer. Producers may hear of someone who has placed urea in direct seed contact and seemed to have no problems, but there are also many cases where urea-containing N fertilizers has injured the developing seedling and reduced or delayed emergence significantly. The risk of injury is greater in drier soils, at higher soil pH levels, and at higher N rates. High soil pH favors a higher concentration of ammonia as compared to ammonium as urea hydrolyzes. There is significant risk associated with placing urea-containing fertilizers in direct seed contact.
The chart below shows how soil texture affected the level of wheat germination when urea-N was applied with the seed in a K-State greenhouse study. The wheat was well watered in this study, but urea-N placed with the seed still reduced germination, especially in the sandy soil. The readings shown below were taken after 10 days. With the high rates of urea used in this study, it is possible that more damage to the seedlings would occur with time as the urea continues to hydrolyze into ammonia.
Field studies have also shown reduced wheat stands due to in-furrow placement of urea. Across 5 site years in western Kansas the placement of urea in-furrow has resulted in decreased stands at spring greenup compared to the control (Figure 2).
The stand reduction becomes especially noticeable at higher rate of N. One of the challenges of understanding the risk of seedling injury is that the magnitude of injury varies by field conditions an years. In some years very little reduction may be evident, even at higher rates of N, while in other years, stand reductions (and their associated impact on yield) is very evident. As an example at Tribune in 2017, reduction in stand caused by urea placement with seed, and their effect on yield were quite evident (Figures 3 and 4).
Stands were reduced 32 and 63% compared to the control when 30 and 60 lbs of N as urea were applied in-furrow (Figure 3). This resuled in yield reductions of 14 and 40%, respectively (Figure 4).
If you’d like to apply extra N directly in the seed furrow, one option is to use a controlled-release form of N, such as ESN. As shown in figure 4, at N application rates of 30 lbs/ac and less, where ESN-N was applied in-furrow, wheat yields were essentially the same as where the N was applied pre-plant, and higher compared to the same amount of N applied as urea. At the highest rate of application in the study, 60 lbs/ac, even ESN resulted in stand and grain yield reductions.
Also, air seeders that place the starter fertilizer and seed in a band an inch or two wide, or side band the fertilizer relative to the seed, provide some margin of safety because the concentration of the fertilizer and seed is lower in these diffuse bands. In this scenario, adding a little extra urea containing N fertilizers to the starter less likely to injure the seed – but it is still a risk.
Here is a great video by Dr. Haag.
Yellow Wheat the 2020 Edition.
I have been trying to write this blog addressing the yellow wheat for about two weeks now. But with finally finding a dry”ish” day or two and a lot of calls and emails about yellow wheat, I am just now getting to it.
So the short story is there is a lot of wheat out there in the state that is show signs of chlorosis, or yellowing. I wish I could say I have all the answers for you in this article, but I will have to lay heavily upon the agronomist best answer, “Well it Depends.”.
Cow pox showing up in a wheat field in Kay County.
First we will start with the things I know least about and then move on to things that are more in my wheelhouse. In the last two weeks I have been on multiple email strings trying to chase down the cause of chlorosis in fields all over the state. One of these included Dr. Bob Hunger and the Plant Disease & Insect Diag Lab (PDIDL) and in one field his final thought was “So, my best guess is cold and wet soils along with fungi colonizing the older leaves that are starting to senesce.” At the same time I am finding regular occurrence of Tan Spot and Leaf Rust increase. All these pathogen cause some level of chlorosis and if you do not get down and pull some samples you will never know the cause.
Originally thought to be leaf rust, but corrected by Dr. Hunger who suggested it is early stages of striped rust, found in Stillwater Oklahoma 3.27.2020.
A new for me this year is what I am calling the herbicide ding. I was able to get over a lot of my wheat that first week of March with a shot of herbicide, everything was almost to hollowstem. The wheat really got dinged. Very visual yellowing and stunting of the plants. Talking with Dr Manucheri, she had seen the same thing in her plots in Tipton. I have also visited several farmer fields with the same symptoms. Dr. Manucheri shared with me the Finesse label. Directly from the label “Temporary discolorations and/or crop injury may occur if herbicide is applied when the crop is stressed by severe weather conditions (such as heavy rainfall, prolonged cold weather, or wide fluctuations in day/night temps), disease or insect damage, low fertility, applications to course soils, or when applied in combination with surfactant and high rates of liquid fertilizer solutions.” This can be found on page 5, http://www.cdms.net/ldat/ldFSL002.pdf . You can just about mark off every weather and application condition mentions, on the same field.
Image collected 3.25.20. The right side was treated with Powerflex on 3.5.20. The left side was not treated so that sorghum could be planted in April.
Now to the yellow wheat I can comfortably talk about. There is nitrogen deficiencies out there. That should not come as a shock with the amount of rain we have received over the last couple months. I also believe that a fair amount of the wheat crop out there is a bit lacking on roots department.
The overarching wet cools soils that we have more than likely have led to reduced root exploration in some areas. And if you combine short roots with a nitrate leaching then the probability of N being out of the reach of the crop is high. Then the question is “Is there still time to do anything?”. The trip I look over the weekend (3/28, 3/29) that encompassed a great deal of the North Central Ok wheat belt showed me that the majority of the wheat had really progressed physiologically in the last two weeks. At this point, a positive return on N investment hinges on the stage the wheat is at.
Our delayed N work over the past several years show that we have maintained the yield on our trials even when fertilizer was delayed into the first week of April. https://osunpk.com/2019/08/14/how-long-can-wheat-wait-for-nitrogen-one-more-year-of-data/
Each graph is from a location where the delayed N study was preformed. The objective of our study was to determine the impact of prolonged nitrogen deficiency on winter wheat grain yield and protein. Eight studies were conducted with 11 N application timings in no-till dryland conditions. A pre-plant treatment of 90 lbs ac-1 of N was broadcast applied as ammonium nitrate (AN). We used AN as our source because we wanted to measure the crops ability to recover and eliminate the impact of source efficiencies. When visual symptom differentiation (VSD) was documented between the pre-plant and the non-fertilized check, i.e the N-Rich Strip showed up, top-dress applications were performed every seven growth days (GDD> 0) (https://www.mesonet.org/index.php) until 63 growth days after VSD at all sites. The only N the treatments received where applied according to treatment structure. No pre-plant N was applied on the trials other than the Pre-plant treatment.
This table shows the application dates of the 10 site years of the delayed nitrogen study. The first column is the location, to the right of the location is two rows the top is grain yield and the bottom is grain protein. Each of the following columns corresponds to an application date. Applications began at each study when the The colors are related to whether that application was statistically (Alpha=0.05) worse than, equal too, or better than applying nitrogen at the first sign of deficiency (0DAVD). For this comparison it is important to know that at no location did preplant have significantly greater yield than 0DAVD.In the majority of those years that first week of April corresponded with the growth stage Feekes 8, last leaf just visible. As the crop moves beyond that point, catching up did not happen. Currently there is wheat out there in the state that has not hit hollow stem (Feekes 6) and there is wheat at Flag leaf (Feekes 9).
The Feekes Scale focused in on the stem extension growth phase. The period extends from hollow-stem (Feekes 6) to boot (Feekes 10).
The high rainfall totals we have could have also led to another deficiency sulfur. In the past S deficiency is fairly hard to find in Oklahoma. Our long history of low S using winter wheat and high sub-soil S levels have kept the response to Sulfur low, but not uncommon. Sulfur is a mobile nutrient and will also be lost via leaching especially in sandy soils in the northern part of the state. Sulfur deficient is different from N in that it shows in the newer growth as a general yellowing of crop. Kansas State has a lot of great resources on sulfur management in wheat. https://webapp.agron.ksu.edu/agr_social/m_eu_article.throck?article_id=2132
https://bookstore.ksre.ksu.edu/pubs/MF2264.pdf
Sulfur deficiency in wheat. Photos by Dorivar Ruiz Diaz, K-State Research and Extension
If your wheat is yellow and before you call the fertilizer applicator, first confirm it is nitrogen and or sulfur and not something else. A key point to nitrogen deficiency is that the cholorsis will be worst on the oldest leafs while new growth is green. If N deficiency is confirmed then figure out how far along your wheat is. If the crop is around hollow stem to Feekes 8, if you can get the N on soon there is a good chance to get your money back plus. Keep in mind with air temps above 60 degrees UAN will burn the tissue so it is best to use streamer nozzles, which will still burn but the tissue damage is lessened. If you do not have access to streamers you can dilute the UAN with water and use flat fan nozzles. Cutting the UAN with water reduce the impact of leaf burn, I typically recommend at least 2 part UAN to 1 part water, but a 1 to 1 is the safest.
Image of wheat with forage burn from UAN applied with streamer nozzles. Application was made two days prior with air temps where above 80 degrees.
If you have any questions or concerns please feel free to email any questions you may have.
Brian Arnall
b.arnall@okstate.edu
Nitrogen source selection, the dollars and cents.
A common question most soil fertility specialist receive goes along the lines of “Where anhydrous ammonia has been one of the cheapest N formulations available, dry fertilizers can also be competitive. From a cost and effectiveness perspective, which is going to be the better deal this year?” This question was recently posed to Agronomist Fields Notes of The Wheat Farmer/Row Crop Farmer produced by Layton Ehmke. What follows is a more in depth version of the response I provide to Layton.
WAKO NH3 applicator used for in-season application.
Unfortunately if all angles are considered this is not an easy answer as determining which nitrogen product is a multi-faceted issue.
First there is the easy aspect, N price. At the time of writing this the local quote at Two Rivers Link is
NH3: 82-0-0 $490 a ton / .30 $ lb N
Urea: 46-0-0 $340 a ton / .37 $ lb N
UAN: 28-0-0 $230 a ton / .41 $ lb N
So on the outside looking in at just the price per 100 pounds of N applied NH3 is $7.00 cheaper than Urea and $11.00 less than UAN.
However the second part of the equation is application cost. Looking at the custom rate for 2015-2016 provide in the OSU Current Report 205 which outlines Oklahoma Farm and Ranch Custom Rates. While these are higher than if the producer owns the equipment it is still a good estimate which accounts for time, service, and repair. The average NH3 application cost is $13.75 while spreading dry fertilizer is $5.41 per acre. The cost of running a sprayer is similar to sprMy Siteeader per acre. So if application and N cost is taken into account at 100 lbs N per acre NH3 is $1.34 cheaper. However the amount of N really impacts this last calculation at 50 lbs of N per acre urea is $4.84 per acre cheaper while at 200 lbs NH3 is $5.66 per acre cheaper.
The third consideration should be the efficiency of the fertilizer. I could and should right a blog solely on the efficiency of nitrogen fertilizer applications. However that is a big mud hole I do not quite have the time to get into. So what follows are a few general consideration. Spring applied urea on no-till will have a significantly higher potential for N loss, from urea volatilization, than NH3 knifed in. Surface applied urea not quickly incorporated in via rain or tillage (added cost) is easily subject to losses greater than 33%. While NH3 applied with proper soil moisture and good seal will have losses in the single digits. The losses from UAN is somewhere between Urea and NH3 as only 50% of the N in UAN is urea. Also method (steamer/flat fan), percent canopy coverage, residue level, and weather will play a part. However is all in is applied pre-plant and NH3 but urea or UAN is applied in season there may be more losses from NH3. The loss of N should be taken into account and added to the cost of N. Lost in could be estimated in two ways, the cost of replacing lost N or the cost of lost yield. To figure replacement take the pounds of N needed (100 lbs) divide by the efficiency, in this case lets say you will lose 20% so 100/.8 = 125. So to get 100 lbs of N to the crop you much apply 125, which increased total N cost to $46.25 per acre. On the flip side if you lose 20% of 100 lbs and needed all 100 lbs of N then you stand to lose (20 lbs N / 2 lbs N per bushel) 10 bushel at $4.00 per bushel.
High clearance sprayer out fitted with streamer bars for UAN application and GreenSeeker RT-200 optical sensors for on the go variable rate nitrogen application.
The final consideration is the ease and or efficiency of use. Some will choose a high priced product because they would prefer not to work with NH3 due to its challenging properties. The ease of use is also where the liquids (UAN) shine. On sight storage of UAN requires the least amount of infrastructure and transport is fairly easy.
The application cost of liquid is nearly the same as dry so considering the prices above 100 lbs of N as UAN will cost $4.00 per acre more. However a 100’ sprayer can cover approximately 30 acres per hour more than a spreader with a 60’ swath (Iowa State Pub). Below is a table that provides a few common applicator widths and speeds. If you consider the average NH3 rig will run 6 mph while spinners commonly run at 12 mph, you can cover significantly more ground with urea. Add to the equation a big sprayer and flat long field and applicators can covers a lot of ground quickly with UAN. So if time is of the essences it makes perfect sense to spend more per pound of N to get it on faster.
Acres covered per hour based on width and speed. High speed not applicable for NH3 application.
In the end the right source often comes down to the specific situation, time, and personal preferences. If you take all of the variables into account, you will be making best decision possible based upon the information available.
If you have any questions or comments please feel free to contact me.
Brian Arnall
Precision Nutrient Management
b.arnall@okstate.edu
2015-16 Wheat Crop Nitrogen Review
From trials to phone calls (and text messages, and tweets, and ect. ect) I have gathered a fairly good picture of this years winter wheat nitrogen story. And as normal, nothing was normal. Overall I seen/heard three distinct trends 1) Did not take much to make a lot 2) took a ton to make a lot 3) saw a response (N-rich strip or cow-pow) but fertilizer never kicked in. Covers most of the options, doesn’t it.
The N-rich strips really came out over all very good this year. N-Rich Strip Blog. On average many of those using the N-Rich Strip and SBNRC (SBNRC Blog) producers have been getting in the neighborhood of 1.0-1.3 lbs of N applied per bushel produced. This year the numbers ran from 0.66 to 2.3 lbs of N per bushel. In both extremes I believe it can be explained via the field history and the N-Cycle.
Nitrogen Cycle Pete’s Sheet
In at least two fields, documented with calibrated yield monitors, the N-Rich Strip and SBNRC lead to massive yields on limited N. One quarter of IBA bumped 86 bpa average on 47 lbs of N while a second quarter, also IBA, managed 94 bpa average on about 52 units of N. We are currently running grain samples from these fields to look protein levels.
The other side of the boat were those with N-Rich strip calling for +2.0 lbs N per bushel. I had received notes from producers without N-rich strips saying that they could predict yield based on the amount of N applied and it was a 2 to 1 ratio. Not always but many of these high N demand fields where wheat following a summer or double crop or corn or sorghum. While many of the low N demand fields were wheat after wheat or wheat after canola. In a rotational study that had been first implemented in the 2014-15 crop year I saw big differences due to previous crop. The picture below was taken in early March. The straw residue in wheat after wheat had just sucked up the nitrogen. While it was evident the residue from the canola broke down at a much more rapid pace releasing any and all residual nutrients early.
The yield differences were striking. The canola rotation benefited the un-fertilized plots by 22 bpa and even with 90 lbs of N applied having canola in the rotation increased yields by 12 bpa. We are looking and grain quality and residual soil sample now. I am sure there will be a more indepth blog to follow.
Canola Wheat Rotation study year two yield average. yields average across previous years N-rates.
Another BIG story from the 2015-16 wheat crop was the lack of benefit from any N applied pre-plant. It really took top-dress N this year to make a crop. Due to our wet early fall and prolong cold winter N applied pre was either lost or tied up late. Work by Dr. Ruans Soil Fertility Program really documented the lack luster pre-plant N effect. The figure below shows 4 location of a rate by timing student. The number at the bottom of each graph is a rate by time (30/0 means 30 lbs Pre-0 lbs Top, 60/30 means 60 lbs Pre-30 lbs Top). At every single location 0/60 beat 60/0. Top-dress N was better than Pre-plant N.
Figure 1. Work from Ethan Driver and Dr. Bill Raun. Study looked at rate and timing of N fertilization in wheat. Treatments are ordered by total N applied.
The last observation was lack of response from applied N even though the crop was deficient. Seen this in both the NE and NW corners. I would hazard with most of the circumstance it was due to a tie up of applied N by the previous crops residue. The length at which the winter stretched into spring residue break down was also delayed.
Take Home
Here it is folks APPLY NITROGEN RICH STRIPS. Just do it, 18 years of research preformed in Oklahoma on winter wheat says it works. Hold off on heavy pre-plant N even if anhydrous is cheap. It does matter how cheap it is if it doesn’t make it to the crop. Will we see another year like 2015-16, do not know and not willing to place money on either side. What we do know is in Oklahoma split applying nitrogen allows you to take weather into account and the N-Rich strip pays dividends.
There are several fact sheets available on top-dressing N and the application of N-Rich strips. Contact your local Oklahoma Cooperative Extension Service county educator to get a copy and see if they have a GreenSeeker sensor on hand.
Some thoughts on pre-plant nitrogen and a little outside the box thinking
It is that time of year, every Co-op I drove by the other day had a line of trucks pulling anhydrous tanks and the spinner spreaders were being loaded. For those of you who haven’t applied your nitrogen yet lets discuss the options traditional and nontraditional.
Anhydrous Ammonia, 82-0-0: by far the most widely used N source is the southern Great Plains. While it is not the most enjoyable to work with it is the cheapest per pound of N and that leads to its wide spread use without Oklahoma wheat production. Just a few simple rules with NH3, get it in the ground and close the row behind you. In conventional till this is usually easier unless the ground is too wet or too dry. In no-till this may be a little more challenging but usually easily accomplished. With the rise in low disturbance applicators I am seeing more and more acres of no-till receiving NH3. Last year I was in a field of stripper stubble and I had a hard time finding where the rig had run, minus wheel tracks.
Urea, 46-0-0: is second on the hit list in nitrogen sales in our state. It is a safe source that is easily handled and applied. In a conventional till system where the urea can be worked in shortly after application it is a very efficient and effective source. Unfortunately when it is applied to the soil surface and rain is the method of incorporation we can experience between 5-60% N losses. The losses come from how urea is converted to plant available ammonium (NH4). For urea (NH2)2CO2, to be converted to plant available NH4 it needs the enzyme urease. Urease is present everywhere but in the highest concentrations on plant residue. The figure below shows the reaction, urease converts urea into NH3 as soon as the prill dissolves. In the presence of moisture the NH3 (gas) is turned immediately to NH4 (solid) and is absorbed onto the soil particle.
Graphic of Urea’s conversion to plant available ammonium.
The problems come when there is no soil particle for the NH4 to bind with. It usually takes 0.50 inches of rain or irrigation to fully dissolve and incorporate urea into the soil. So if we only get a few tenths or hundredths, even heavy dews, some of the urea will dissolve, be converted to NH3 then NH4 and be left on the plant/residue. When the moisture dries, some or all of the NH4 goes back to NH3 and will gas off into the atmosphere. I have even seen this happen when urea is applied on a wet/damp soil, not incorporated and it doesn’t rain for significant period of time. If the temps are cooler the urease is slower so less of the urea is converted to NH4, but if the temps are warm 60+ degrees these little enzymes can act very quickly.
Urea placed on the surface of a wet soil under two temperature regimes. White text is the number of hours after application.
Urea placed on dry soil, Top row: dry soil no water added, Bottom left, moisture added from subsurface, Bottom right : simulated rain fall event of 1/2″. White text is the number of hours after application.
Below is a short video on using urea fertilizer.
While the recent rains are a blessing and will surely help germination, it is not aiding our N use efficiency especially in no-till. That is why in some parts of the state you may see some grain drills running right now. Some of those producers are not planting wheat they are actually applying there pre-plant urea. I have even been told in the SW part of the start some producers are using air-seeders to apply their urea. While this seems like a costly venture I have worked with the Ag Economist to create a calculator to figure up the break even for when it would pay to use an air-seeder over the traditional spinner spreader in no-till. We hope to put the finishing touches on it in the next few days. When it is completed it will be shared on this blog.
Liquid Urea Ammonium Nitrate, 32-0-0 or 28-0-0: while this is one of the more expensive forms of N many producers are utilizing this source because the can pre buy and store on site and as sprayer get larger they can cover a significant amount of ground quickly. For the most part UAN is used in no-till and is a great source. I always recommend that applicators use streamer nozzle or streamer bars to apply UAN. When UAN is applied via a flat fan nozzle it spreads the fertilizer across the residue allowing a significant portion to be tied up. The streamers concentrate the fertilizer into streams/bands reducing contact with residue and increasing the amount of UAN that reaches the soil surface.
Timing and Rates
The cost of anhydrous, about $0.1 to 0.12 less per pound N less than urea is driving its use this year. The lower price is also driving a significant about of producers to go with 100% of their N pre-plant. While this makes for sound economics now having all of your N upfront is like putting all of your eggs in one basket. If we do get that cold and wet winter as some are calling for this presents a great chance for the N to move down the soil profile and down the slope. I have always recommended split application. This allows a producer to judge the crop throughout fall, winter and even yearly spring and adjust his or her N plan accordingly. For those who plan to graze there is still a need to get enough N down to produce fall forage, this may be 50 to 80 lbs of N, but for grain only production planted later in the fall a typical crop may only need 20-30 lbs of N before going into winter. The old rules of thumb, 2 lbs N per bushel and 30 lbs N per 100 lbs of gain still work and are better than a guestimate but we have better ways. Right now is the time to plan to apply N-rich strip, a strip in the field with 40 to 50 lbs more than the rest of the field. These strips can be applied with a variety of applicators, but as long as the N goes down in at least an area 10 ft wide by 300 ft long it is good to go.
Just a few of the applicators used for putting out N-Rich Strips. ATV Sprayer, Receiver Hitch mounted Sprayer, Road sprayer with a rear boom, pull type spinner, large sprayer, push spreader. Not shown is NH3 applicator.
Below is a N-Rich Strip 101 video.
If you have got the N-Rich strips out you can set back and watch to see when and if they develop. If you can see the strip you know you need too fertilize.
While many are not ready to think about top-dressing yet, it is never too early. Don’t be afraid to think outside the box. Oklahoma’s springs tend to present the perfect conditions for N loss when urea is the primary N source. This year in a 4R Top-dress Nitrogen Application Demo, at Lahoma and Chickasha, we are going to apply just about every available commercial source in about every possible manor. Urea will be broadcast, coated with inhibitors, applied with a grain drill, NH3 will be knifed in, and UAN will be applied with flat fan nozzles, streamer nozzles and knifed in. As technologies improve and the cost of N remains relatively high the options for top-dress N application will continue to improve. The economics of wheat production don’t look great right now so don’t be afraid to think outside the box, even if it does raise the eyebrows of your neighbors. Fill free to contact myself or your local extension educator if you have any questions about N application.
John Deere double disk drill used to apply urea in-season.
WAKO NH3 applicator used for in-season application.
Down and Dirty with NPK 