Tuesday, April 19, 2011

Anhydrous Ammonia Application

Today is a cold, damp, yucky day.  So, I'm going to take you back to about 10 days ago when it was warmer, drier and we were applying anhydrous ammonia (NH3). 

Anhydrous ammonia (NH3 for short hand) is the form of nitrogen we use in our farming operation.  There are several different forms of nitrogen fertilizer - liquid 28% and 32%, urea, ammonium sulfate - but in our operation NH3 is the best form to use.  Corn being a grass plant requires nitrogen to grow. The soybean is a legume and manufactures it's own nitrogen.

Tractor, NH3 Tool Bar and NH3 Tank
The NH3 applicator is the first tool we take across our fields in the spring.   Behind the tractor is what is called the NH3 tool bar.  It is 47 feet wide.

A view of a coulter.
View of the front of tool bar.

On the front of the tool bar is a row of large, sharp, round blades called coulters.  The coulters cut through the plant residue. 

Next, there is a row of knives.  There are 17 knives on this bar.  Each knife is curved and has a plastic hose running down the side of it.  This tube carries the nitrogen from the tank into the soil.  The knives go about 8 to 10 inches deep and this is where the nitrogen is placed.  The closing disks then seal the nitrogen  
View of a knife and closing disks.
into the soil right behind the knives.  There are two disks behind each knife that form a V to get the soil over the knife opening.

Behind the tool bar we pull the anhydrous tank.  There is enough nitrogen in this size tank to apply about 17 to 20 acres at the rates we use.  Anhydrous ammonia has an extremely low boiling point so the tanks are pressurized.  The NH3 is a liquid in the tank but when it hits the soil it turns to the gas form.  That is why it is important to have good closing devises behind the knives. 

A large hose runs from the NH3 tank to the cooling tower on the tool bar.  From the cooling tower smaller hoses take the NH3 to each knife.  Joe will probably cringe when he reads this since I have skipped a lot of the details but that is the gist of this implement. 

It takes us about seven days of running to get our nitrogen applied.  Joe usually starts in the morning about 5:00 am.  My dad replaces him about 7:30 am.  Joe then replaces Dad again about 8:00 pm and runs until midnight.  We have a retired gentleman who hauls NH3 tanks all day long back and forth from our supplier's facility and our fields.  
 I should make one comment about these pictures.  When we were putting on NH3 it was very dry.  We had not had any precipitation for a few weeks so it was very dusty out in the field.  So that is dust not NH3 behind the tractor.


  1. man pretty hard work.All day until midnight.Plus there was a dude who did this for the whole day. ISn it just nitrogen fertilizer you guys use,or is it mixed fertilizer containing nitrogen?

  2. We apply the NH3 prior to planting. Then after we have planted we spray another 40 units of N using 28% with herbicides pre-emerge.