Nitrogen Loss in Saturated Soils

Nitrogen Loss in Saturated Soils

Nitrogen management Nitrogen Testing

We sometime hear that lots of rain will leach our nitrogen fertilizer.  My experience is that unless the soils are very sandy, most of the nitrogen loss will be from denitrification.  In other words, the nitrate nitrogen is converted to unavailable forms. Losses will be much less on recently applied anhydrous ammonia than on fields where nitrate forms have been applied, or where early applied nitrogen has already nitrified. This article out of Mississippi puts some numbers to it.  In warm weather we can lose up to 5% a day.  Some testing might be in order when soil have dried out.  When oxygen gets back into the system, There will be some renitification.  Cultivation can encourage that, but it will not take the place of fertilizer entirely.  You models such as Climate or Yield 360 can be useful too, but I do not trust them entirely.

Nitrogen Management Webinar

Nitrogen Management Webinar

Nitrogen management

Emerson Nafziger is present a nitrogen management webinar on recent research next Thursday, March 30.  Click on the link for more info and to get registered.

Should You Split Your Nitrogen Application?

Should You Split Your Nitrogen Application?

Nitrogen management

Emerson Nafiziger discussed likely changes in removal rates for P and K at this year's crop management conference. Removal is not a good way to make fertility decisions.  You need to know what you have.

He also briefly discussed return to Nitrogen Dollars.  At least in 2016, split applications did not pay. Maximun return to N was at relatively low rates.  Check out his comments on nitrogen.  I would not change my application method because of this research, but you might want to look at the Nrate calculator to help in your rate decision.  My recommendation would be to go to the high side of the chart.

If you are applying Nitrogen right now you should be treating it as a fall application and use inhibitor.  A warm wet March would denitrify a lot of N.

Carbon Nitrogen Ratios

Carbon Nitrogen Ratios

cover crops Nitrogen management

Carbon Nitrogen Ratios were studied at University of Nebraska to see how much nitrogen is contributed to the next year's crop.  It is interesting that in looking at Carbon Nitrogen Ratios in cover crops that it appears that a high tonnage crop like cereal rye may actually contribute more nitrogen than a legume crop that fixes nitrogen from the air.  I would like to do some in season nitrogen testing to confirm this, but it looks interesting enough to pass along for consideration.

Field Activity

Field Activity

field activity Nitrogen management

Weather has been good for a while now, so there is lots of field activity.  I saw someone today using a ditcher with survey grad GPS.  I am sure I could still find corn and soybeans to harvest, but harvest is 99% complete.  Lots of people were doing tillage today.  Also lots of people applying anhydrous ammonia.  Jut a reminder that it is surprising when fall applied nitrogen is reduced to half by planting time.  I saw several people applying fall weed control measures today too.

Fall Nitrogen Management

Fall Nitrogen Management

Nitrogen management

Suppliers and farmers alike seem to like the idea of fall nitrogen application.  I saw a post yesterday that soil temperatures in Mid-Illinois are at 50 degrees making fall nitrogen application seem like  a good idea.  Keep in mind that soil temperatures can vary as much as 10 degrees depending on bare soil or covered soil.  I suggest checking each field at a 4 inch depth before applying.  The Illinois Water Survey posts temperatures daily.

Last fall November soil temperatures were favorable for applying nitrogen.  Then in December we warmed up.  by April, I started nitrogen testing and found that most people had lost half of their fall applied nitrogen.  If you insist on fall application, be sure to use nitrification inhibitors.  Split applications are a better idea than applying all at once.

No-till Farmer published a list out of Illinois of 10 Practices for cutting tile nitrate loads.  Tile is only one way that nitrogen is lost.

Running out of Nitrogen

Running out of Nitrogen

Nitrogen management Nitrogen Testing

I made a trip to Virden today to have my truck worked on,  The most interesting thing I saw is that much of our corn appears to be out of nitrogen.  Especially in wet area.  If you want a post mortem to see how you did in supplying your corn with nitrogen, you should look into doing some stalk nitrate testing.  Combining with a soil nitrogen test is a good idea to.

Nitrogen Management update

Nitrogen Management update

Nitrogen management

My most frequent topic is nitrogen management.  Nitrogen management is elusive.  If you have read this blog, you probably understand that applying nitrogen based on yield goal is the least preferred method.  June Prairie Farmer did a good job of summarizing Nitrogen Management Techniques available.  Read the second page as well.

Spring Nitrogen

Spring Nitrogen

Nitrogen management

We are seeing some spring nitrogen application beginning.  There are a few concerns with applying nitrogen right now.

• Are your soils dry enough?
• Will it last until you need it?

If you are applying nitrogen to wet soils, you may be losing some because your slit is not closing well.  In addition, you may be creating compaction that will bite you if we have a dry summer. Wait until the soil is dry enough to do a good job.

Corn does not really need much nitrogen until it is nearing the reproduction stage.  Early applied nitrogen will start to nitrify as soil temperatures warm.  The process does not take long.  Once you have nitrogen in the NO3- (Nitrate) form, it can be leached or dentrified.  Both processes make it unavailable to the plant later in the season.  I think you should use nitrification inhibitors for early spring applications.  The question is, "Will it Pay?"  Maybe, maybe not, but it is a good practice environmentally and therefore pays off long term instead of short term.  This can be one of your strategies for the nutrient loss reduction program.  Keep it out of the Gulf.

Illinois Nutrient Loss Reduction Strategy

Illinois Nutrient Loss Reduction Strategy

Nitrogen management Nutrient Management

Today I attended a meeting on the Illinois Nutrient Loss Reduction Strategy.  It looks like the information push is on; there was an article in FarmWeek News this week.  The meeting went over what can be done to reduce nitrogen loss and phosphorous loss.  Then  there was a discussion on programs available.  The final presentation was on drainage water management.

One of the things that caught my eye is that water testing is available so you can have your drainage water tested for nitrates.  I have always thought this was a good idea, but never got anyone to do it because I had to charge for it.  Click on the link to find out how to collect you samples and where to take them.  The testing is confidential, but gives yo an idea whether or not you need to do something about nitrogen management on your farm.

Nitrogen Management on Wheat

Nitrogen Management on Wheat

Nitrogen management Wheat

Years ago, it was common practice to apply nitrogen to wheat at this time of year on frozen soils.  For environmental and agronomic reason, that practice is no longer seen as a good one. Illinois researchers have found that mid to late March is good timing for many growers in Illinois.  This information out of Kansas discusses Top-Dressing Nitrogen on Wheat.  

Nitrogen Management in Illinois

Nitrogen Management in Illinois

Nitrogen management

Last week I attended the Illinois Crop Management Conference in Mt. Vernon.  One of the presentations was by Emerson Nafziger.  Dr. Nafziger is the senior agronomist at the University of Illinois.  He discussed his latest research on nitrogen management and use efficiency.  He was looking at the effects of such things as split applications or late applications.  He explained the value of the N-Rate calculator which I have previously discussed.

His results were sort of spotty.  In some cases, the split rate did as well as the full rate applied in spring.  In some cases, split rates did better.  His point was, that later in the season application rates can get expensive and troublesome considering extra machinery required and weather issues.  He says you should think twice before jumping in with both feet.  His results were not necessarily consistent with what others have found.

One of the flaws in his study that I caught, was that he equated dribbling UAN in the middle of the row with using Y-drops.  This misses the point of Y-drops entirely.  The Y-drops put the UAN neat the base of the plant where there is at least theoretically a little extra moisture to stabilize the UAN and maybe help with uptake.  I thought Emerson made some good points, but his research results were only from one year.

My bottom line is that you should not draw any conclusions from the U of I work at this time.  If you are using some sort of split application method, don't let these results deter you.  If you are considering a big purchase however, I would hold off on it especially in these lean times.

Nitrogen Loss from Recent Rains

Nitrogen Loss from Recent Rains

Nitrogen management

A wet fall in general , and recent rains in particular have people thinking about nitrogen loss where it was fall applied. Fall applied nitrogen that was applied late, will experience less loss than early applied nitrogen especially when soil temperature are above 50 degrees Fahrenheit since it has been applied.  There is not much that can be done at this point whether you have nitrogen loss or not.  The best time to look at it is shortly before or after planting.  A soil test is the best way to find out what is going on with your nitrogen.  Another alternative is to take advantage of chlorophyll sensor technology at sidedress time.  The sensors will help to deal with the fact that losses are expected to be higher on low areas.  No-Till Farmer has written about 5 factors that affect nitrogen loss.

Fall Nitrogen Application

Fall Nitrogen Application

Nitrogen management

Some producers are starting to apply fall nitrogen.  Whether or not this is a good idea remains a big question.  Iowas State offers some advice on Determining Whether to Apply Fall N.  In Illinois, the recommendation is to use nitrification inhibitors and don't apply south of Route 16.  Also, wait till soil temperatures drop below 50 degrees Fahrenheit with little chance to warm.  My advice would be no fall application south of I-72 and no fall application before Veterans Day in any case.  Illinois Soil Temperatures are cooler than I expected according to Illinois Water Survey.  Keep in mind that temperatures on your farm may vary up to 100 degrees depending on conditions.  Check at a depth of 4 inches at 10 AM.  A $5 meat thermometer works fine.  Let it in for at least a minute.

Stalk Nitrate Testing

Stalk Nitrate Testing

Nitrogen management

As we see corn get more yellow every day, we might want to know how we came out on nitrogen.  One way to make that estimate is to take a stalk nitrate test.  The test should be done after black layer or maturity.  I took Stalk nitrate test and also pulled soil samples for nitrogen analysis. It is possible that the tests will not match.  The soil test gives you a chance to do extra thinking about what might have gone wrong, or right.  No-Till Farmer has an article on late season nitrogen assessment.

Illinois Nutrient Loss Reduction Strategy

Illinois Nutrient Loss Reduction Strategy

manure Nitrogen management Nitrogen Testing Nutrient Management

Illinois is implementing a voluntary nutrient loss reduction strategy.  The strategy was developed by the Illinois Department of Agriculture, the University of Illinois, The fertilizer industry, and commodity groups active in Illinois.  The purpose of the strategy is to reduce nitrogen and phosphorous entering the hypoxia zone in the Gulf of Mexico. You can help to implement the strategy by applying phosphorous and potassium according to soil test indications.  You should consider applying nitrogen according to the Nrate calculator.  In season nitrogen tests and chlorophyll sensors are practices that might be useful to make in season corrections.

Another key to reducing nutrient loss is reducing soil loss on your farm.  High residue levels and no-till are very effective in soil loss reduction.  Sediment basins, grassed waterways, and filter strips can also be useful in keeping nutrients on the farm.  Safe manure handling is also part of the strategy.  It is time for farmers to get serious about the strategy to avoid further regulation.  A lot of environmentalists are saying it can't be done.  We all need to work together to prove them wrong.  

Nitrogen Sampling Time

Nitrogen Sampling Time

Nitrogen management Nitrogen Testing

We have been sampling for pre-sidedress nitrogen testing the last few days. This is not one of my favorite jobs, but it is the best way to find out what is going on with your nitrogen. Corn in Western Jersey County is 6 inches tall.

Soil Fertility - Nitrogen

Soil Fertility - Nitrogen

Nitrogen management

I think nitrogen management may be the topic I have written about most. In our seminar on Friday, the most covered topic was nitrogen management. Everyone wants to manage nitrogen in such a way that they maximize corn yields.  With concerns about Chesapeake Bay, Lake Erie, and Gulf Hypoxia, good nitrogen management is also needed to be environmentally sound in our practices.  In addition, many people are concerned about the nitrous oxide released into the atmosphere.

Testing for nitrogen to determine rates can be done in a number of different ways.  Our Soil Health Test can help determine how much nitrogen release to expect from the soil.  The Presidedress Nitrate Test can help determine if additional nitrogen is needed at sidedress time, or at any time you can apply.  The stalk nitrate test, done after black layer, can help determine if the crop had too much, too little, or enough nitrogen available to take the crop to maturity.  Nitrogen sensors are available if you are comfortable with them to do rescue treatments on wet soils.

Setting a base rate is also a challenge.  Emerson Nafziger made a good case for using the Nrate calculator to initially determine how much to apply.  He did present some information to show that producers can come up just a bit short with the Nrate calculator.  One way to adjust for that issue would be to go with the maximum rate on the chart instead of the average rate. I was not overly impressed with the results of using the Adapt-N program.  The bottom line is, some producers should be looking to low nitrogen rates to be more environmentally sound.  If you are still looking for ways to cut back on inputs this year, the Nrate calculator might help you make sound decisions about the economics of your nitrogen rates.

Applying Nitrogen to Winter Wheat

Applying Nitrogen to Winter Wheat

Nitrogen management Wheat

I can remember  a time when nitrogen was applied to winter wheat in February.  Researchers have found that this is not a great idea.  There is some discussion about split application in wheat.  In my mind DAP applied in the fall constitutes the first application of nitrogen.  If the DAP is applied later in the fall, cold weather will help preserve the nitrogen for spring growth.  The early boost of nitrogen can increase tillering.  It is much more efficient to apply nitrogen later in the growing season.  Nitrogen can be applied well into April, putting on the crop when it is most needed.  Pioneer Seed looks at nitrogen on wheat and refers to Illinois research.

Judge Rules that Manure is a Pollutant

Judge Rules that Manure is a Pollutant

livestock Nitrogen management

A Federal Judge has ruled that a dairy farm in Washington is polluting ground water by over application of manure.  His ruling may change how manure application is regulated.  I suspect the case will go to the Supreme Court because the judge is ruling based on an act that specifically exempts manure application when it is used as fertilizer.  The Yakima Herald Republic seems to have the most complete story.  Click on the link. 

My comment is that farmers need to be diligent in how they manage manure and fertilizer in order to be seen as good neighbors.  In Illinois at least, Farmers must prove in their CNMP that they have enough land to properly apply the manure at rates that will minimize pollution.  The ruling also cites the fact that application records are incomplete.  One of the things we stress, is to keep good records.  One of our consultants works with a manure hauler who keeps application records on rate and location by GPS.  I am not sure how the plaintiff in this case proved that all of the pollution was caused by the dairy farm.  It seems to me that it would be a difficult case. 

This case certainly goes hand in hand with the case where the City of Des Moines is suing counties upstream for excessive nitrates in the Des Moines River.