Practical Guidelines for Applying Anhydrous Ammonia in a One Pass Seeding Application

Thom Weir

ACE Specialist

Westco/SWP

Yorkton, Saskatchewan

We would like to offer the following tips for your consideration. They have been developed mainly from working with and observing what your fellow farmers have done in the past few years. They are not the definitive answer but may save you some time re-inventing the wheel or some frustrations.

1. Select an opener or seeding system that satisfies your requirements for soil disturbance.

2. What do you really want for a seeding system? Generally, lower disturbance will also give reduced seed/fertilizer separation.

   Understand the benefits and shortcomings of the various disturbance systems. Look at the advantages of soil disturbance for weed control as well as the advantages of low soil disturbance. These advantages will change from soil types and soil zones. For instance, higher disturbance seems to lend itself to heavy clay soils, especially in the black soil zone whereas a low disturbance system may have advantages in light soils or in the dryer soil zones.

   Direct seeding openers will give a disturbed area of approximately .25 to .50 of the width of the opener. Therefore, a 2" wide opener, with a little bit of soil build up on it, may disturb a width of 3". This will include soil throw. This width may be increased if speeds are above 5 MPH.

3. Ensure you have 3/4" to 1" separation of seed and fertilizer. Determine the separation of seed and NH₃ using the Westco NH₃ Detection Kit.

4. Separation of the seed and fertilizer is imperative to ensure the crop grows. A disclosure of the ammonia in the soil will allow you to properly determine your margin of safety. You should make a minimum of 4 disclosures / field or crop. Also, you should excavate approximately 1 ft. of row to ensure that seeds are not falling into the fertilizer row.

5. Don't over commit your horsepower requirements.

1. Packing is very important.

2. Ensure the seeding system you choose has an "on row" packing system that is matched in width to the seeding system. Ensure that the entire seedrow is being packed. The precise shape and material that your packer is made of and packing pressure will vary with soil and environmental conditions.

   Packers come in various arrangements including "Shank Mounted", Gang Packers and Individual Rear Mounted systems along with random packer system.

3. Check openers regularly for wear.

4. As openers wear, their configuration changes. This wear may result in a shallower placement of fertilizer, thus nearer the seed. It may result in the loss of the shelf that the seed is placed on so as not to fall into the fertilizer trench or it may result in a change of the angle of attack of the opener and flatten out the opener. Check behind wheels for wear first. A good idea is to carry a new opener or point to compare wear with those currently being used.

5. Insulate your ammonia tube from the metal of the opener. This will help eliminate soil freezing and building up on shanks. An insulator may be required to separate the NH₃ tube from the metal of the opener. One way to do this is to use spray foam insulation in the fertilizer port of the opener to hold the NH₃ tube in place. A piece of belting between the opener and the shank can also be useful.
6. Ensure equal distribution of NH₃ across the width of the machine. We recommend that you use a manifold that separates vapour form liquid as in a Vertical Dam Manifold (V.D.M.) system. Also make sure all hoses are the same lengths, orifices the same size, manifolds and tees are level and barbs and plugs are evenly spaced around the manifold.
7. Use an electronic metering device with a heat exchanger that will accurately apply the proper amount of product. These rate controllers will also allow for tank by tank monitoring of product. This will ensure that you are applying the rate that you wish.
8. Check your application rate when changing tanks to ensure your meter is applying accurately.

9. You may not be concerned if you have a mis-adjustment of settings and are out be 30 lbs. of fertilizer on a field if you are banding it. However this can spell the difference between having a crop or not in a direct seeding system.

10. Start out Cautiously.

Always observe recommended safety precautions when handling NH₃.