Herb Bartel and his son Craig of Lanigan have been using anhydrous ammonia in a one pass seeding system for three years with excellent results. The first year Herb seeded with ammonia it was a dryer year and he tried several strip trials of different rates. On cereals he went up to 70 lbs. of actual N. He saw no evidence of fertilizer damage. In fact at harvest time he says he wished he would have used 70 lbs on everything because of the higher yield he observed on the cereal trials. He also went up to 75 lbs on canola. Although he didn't see yield improvement there was no damage!
The Bartels seed with a 4480 Harmon Airdrill. The u nit they are running now has 12 in. spacing. This replaced the previous machine which had 8 in. spacing. One of the main differences that Herb comments on is that the narrow spaced machine sometimes plugged in heavy residue.
The opener that the Bartels use is Harmon's double shoot opener. Fertilizer is knifed in with a bullet shaped eagle beak. A paired row splitter places the seed to either side of and shallower than the fertilizer. This year Herb was able to get his air velocity down to the place where he is getting two distinct rows about 2.5 in. apart. On this particular opener the splitter can be raised or lowered in comparison to the fertilizer beak opener. This allows fertilizer depth to be varied while keeping seed placement depth constant. Another boot has been placed between the knife opener and the seed splitter. It gives Herb the option to triple shoot.
The machine is set to place the anhydrous ammonia about 2 in. deep and most of his seed at the 3/4 in. depth. Herb says when Westco used their ammonia detection kit this year they found that he had separation of about a loony and a half between the seed and the ammonia band. They said a loony would be adequate. One of the problems encountered with using ammonia is that the opener can freeze up and then soil begins to freeze to the opener as well. Eventually the opener becomes a big ball of soil. Herb finds that running the plastic ammonia line all the way to the bottom of the opener so that no ammonia touches the metal of the opener has eliminated the freezing problem. Harmon uses a hollow shank to the fertilizer beak. Herb found that the air delivery system used to place dry fertilizer down with the ammonia blew ammonia out of the soil. Triple shooting has helped to solve that problem.
Herb has spent a lot of time re-manufacturing the air seeder cart and the ammonia tank to make a system that he was happy with. Last year they used a 1500 gal tank with 16.5L-16.1 tires but the rounded surface of the tire cut too deep leaving ruts. Last winter they modified it with 18.4-26 combine tires and Herb says it really reduced compaction and saved them from getting stuck on a wet year like this one. Herb has turned a Prasco air tank into a tow behind 3 tank system using a Morris air delivery system. He has a total capacity of 300 bu. and uses 18.4-26 tires on the front and 23.1-26 tires on the back. The ammonia tank tracks inside the air seeder tank tires.
As far as doing a good job of direct seeding Herb says that one of the critical things is a good residue spread. They use a Kirby spreader but it is difficult to make it do really great job on a Gleaner combine. Herb uses a heavy harrow on heavy residue cereal stubble in the fall. They farm on soils with mainly a sandy loam texture. Although they were able to start seeding as early as their conventional neighbours they could not make as good a time because they had more slippage especially on those fields where there was a mat of residue. Herb feels that more heavy harrowing could really eliminate some of these problems.
Some other important direct seeding practices that Herb follows are a good rotation that looks like this most of the time: pea - cereal - oilseed - cereal. Spring burn-off is also a direct seeding practice Herb follows. He is starting to use more preharvest Roundup and expecting that preharvested fields may not need the spring burn-off.
Herb and Craig seeded about 4500 acres this past spring. 1500 acres were custom work. I'm sure if you have any questions about how they do it Herb would be happy to talk to you.