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A New Approach To NPK

The fertilizer is in the ground, but Ken Dechant still has a wait-and-see attitude on whether a relatively new concept in banding anhydrous ammonia and other nutrients will produce all the benefits manufacturers of the system claim.

Dechant switched his whole farm near Manning in Alberta’s Peace River region to the Exactrix and TAPPS fertilizer system last fall. Both those terms — Exactrix and TAPPS — are not exactly household terms for most farmers in Western Canada.

Exactrix, developed in the 1990s with the first unit sold in 1998, is equipment for pressurizing anhydrous ammonia on your seed drill or fertilizer tool, so the NH3 maintains consistent pressure and remains in the liquid form until it is banded into the soil. There are other similar systems on the market. The concept is that without consistent high pressure through the delivery system, the anhydrous can convert to gas, freeze the tip of the opener at the ground and cause balling up of soil and spotty application in the band row.

TAPPS, which actually has been around since 2002, stands for tri-ammonium poly phosphate sulfate, the name given to a fertilizer created when anhydrous ammonia and liquid phosphorous and sulphur are combined in the soil. The three components in TAPPS are anhydrous ammonia, or NH3, ammonium polyphosphate (APP) in liquid form (10-34- 0) and ammonium thiosulphate (ATS) with a analysis of 12-0-0- 26. Often zinc is included in the blend as well.


Guy Swanson, developer of the Exactrix system and marketer of the TAPPS process says TAPPS isn’t something you can buy, it has to be created in the soil. “When anhydrous ammonia, APP and ATS collide in the soil there is a chemical reaction as they combine to create TAPPS,” he says. At the moment of contact the compounds actually crystallize in the soil.

Swanson, who is based at Spokane, Washington, says researchers have known about the process that creates TAPPS for some time, but it wasn’t until he developed the Exactrix formulator for injecting and combining all three products that it became possible to bring the products together in the field to form TAPPS.

In a fall application setting, the crystallized TAPPS material is very stable, and remains in the soil and breaks down with temperature and moisture to become “the most plant-available form of placed nitrogen, phosphorus, sulphur and zinc,” says Swanson.

And that’s the big selling feature — it’s billed as a system that requires less fertilizer and increases yield.

Nitrogen, phosphorus and sulphur are banded together in the soil to create TAPPS, and seed is planted directly above the banded fertilizer. Swanson says his research and dozens of on-farm trails across the U.S. and Canada shows the form of the nutrient is very stable, but because it is also so much more plant-available, less fertilizer is required.


Swanson says that TAPPS provides 166 per cent more crop available nitrogen and 200 per cent more crop available phosphorus than the dry form of these nutrients.

“Applying 100 pounds of nitrogen through TAPPS is like making 166 pounds of N available to the crop,” he says. “And because the phosphorous is 200 per cent more crop available, if you normally apply 40 pounds of 11-52-0 per

acre, you can reduce that to 20 pounds of P with TAPPS.”

With February 2011 pricing, Swanson says these forms of fertilizer are much more cost effective. He says anhydrous ammonia costs 40 cents per pound compared to urea at 50 cents. But because urea is less efficient its true cost is more like $1 per pound. And while he notes that liquid poly phosphate is 150

per cent the price of dry phosphate 11-52-0, again because it is twice as efficient, the real cost of the liquid is 97 cents per pound compared to 11-52-0 at about $1.34 per pound.

Swanson says farmers cannot only reduce the amount of fertilizer applied, but should also see yield increases. His research with farmers shows through using TAPPS long-term nutrient efficiency is improved, increasing crop yields by 10 to 20 per cent.


“The additional net margin from using TAPPS to grow wheat is $30 to $120 per acre,” says Swanson. The Exactrix system itself isn’t cheap; a basic injector system costing about $30,000 and up to about $150,000 depending on size and features. He estimates it may cost about $45,000 to adapt the system on a 25-to 30-foot toolbar.

“But the system can more than pay for itself the first year,” says The Exactrix system delivers anhydrous ammonia, liquid phosphorus and sulphur at once. The system costs anywhere from $30,000 to $150,000 depending on size and features.

Swanson. “A producer cropping about 2,000 acres, for example, should realize an extra $50 per acre margin. That’s about $100,000 increased return, for an investment of less than $50,000, and that’s in one year.”

Swanson does offer a buy-back guarantee, but only for a portion of the original purchase price. Farmers need to establish a series of test plots comparing Exactrix and TAPPS to the conventional system. These plots are to be properly monitored. And the Exactrix and TAPPS formulator is to be used with a single disc tool bar set up on a minimum of 10 inch to no more than 15-inch row spacing. If, following those parameters, the system does not improve crop margins, Exactrix will buy back the system at one-third the original investment at the end of two years.


Dechant, who is always open to trying new ideas, says he hopes the yield increases materialize, but he’s also looking toward other benefits from the Exactrix/TAPPS system. Those other benefits include saving time and increasing crop quality.

He says applying anhydrous and liquid forms of phosphorus and sulphur should be much more efficient and less time consuming both in handling and in application.

“We have a very short growing season here, so every day counts,” says Dechant. “You don’t have to go too many miles south of us here, and they can be out seeding two weeks earlier than us in the spring and be combining two weeks earlier in the fall. So it is important that we are as efficient with our days as possible.”

Dechant developed a 64-foot Case SDX toolbar to apply the anhydrous, phosphorus and sulphur products, which are carried on a 70,000-pound track cart behind the cultivator. The cart has 8,556 square inches of track which carries the load with no sign of soil compaction. He pulls the unit at eight miles per hour with a John Deere 9530 T track tractor.

The system was used for the first time in the fall of 2010 and the first crop will be seeded this spring. Dechant says he plans to use the Exactrix/TAPPS system right behind the combine, and he also hopes to incorporate an RTK guidance system into his seeding system so he can seed directly over the banded fertilizer row.

“I don’t have enough experience with the system to know whether it will do everything it is supposed to do,” he says. “It is a more efficient way of handling large quantities of fertilizer which saves us time. Hopefully there is a yield increase, but I’m also hoping there is an improvement in wheat protein. We’ll see what the system does over the next few years.”

LeeHartisafieldeditorforGrainewsat Calgary.Contacthimat403-592-1964orby emailat [email protected]


TAPPS isn’t something you can buy, it has to be created in the soil

About the author

Field Editor

Lee Hart

Lee Hart is editor of Cattleman’s Corner based in Calgary.



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