Paradigm Shift
Introduction of Side-Banding
When side-banding was first introduced, nitrogen placed one inch below and to the side of the seed was accepted as the ideal location for adequate fertilizer separation from the seed. Many companies released various side-banding systems which were developed with the belief that this distance would protect the emerging crop.
The first major downfall that was realized with side-banding systems was the openers could not produce an adequate field finish, allowing the seed and fertilizer to mix, seed to germinate at various seed depths, and the soil moisture to evaporate.
Manufactures attempted to redesign existing side-band openers, release new openers, or suggest practices that would help improve the seedbed quality, but seriously impede the producers efficiency. Minor improvements were noted in certain locations or conditions, but overall the results were similar to before.
Initial Recommendation for Side-banding
Poor Seedbed Results from Double Shoot Seed Boots
Fertilizer Proximity an Issue
A second major downfall to side-banding began to emerge at this time. Fertilizer damage was being noted more as the implementation of side-banding grew. The initial assumption of 1" x 1" of separation was found to be too close to the seed. Studies were conducted that confirmed that nitrogen fertilizer can have negative effects on the seed due to its proximity.
Manufacturers now scrambled to increase the seed-to-fertilizer separation of their systems. New side-banding products such as paired row openers and dual knife came onto the market which advertised a greater degree of separation. Again, each of these systems were prone to both seedbed disruption and inadequate fertilizer separation. In some cases, additional issues of poor residue flow, reduced seeding speed, and increased draft resulted from these new designs.
Toxic Ammonia from Fertilizer Band Puts Seed at Risk
Fertilizer Damage will Create Serious Setbacks in the Crop
Fertilizer Management in One-Pass Seeding Systems
from a January 2005 AAFC Presentation
  • Side-banding places the fertilizer to the side and below the seed;
  • Often the entire nitrogen needs can be met;
  • One inch by one inch separation may be insufficient;
  • Two inches to the side by two inches below may generally be safe;
  • High distribution may dry and disrupt seedbed;
  • Side-banding safer than seed placement of nitrogen
Note that 2” by 2” separation is considered safer than 1” by 1”, yet few if any side-band system can deliver this range of separation. An opener that provided this amount of separation would create even more soil disturbance and soil fracturing than existing systems.
Soil fertility considerations when dealing with dry seeding conditions
Manitoba Agriculture from Apr 26, 2002 report
  • Side banding of N to the side and below the seed will decrease the risk of ammonia toxicity compared to seed placing. Often the entire N needs of the crop can be met through sideband placement, but recent research indicates that placement 1" to the side and 1" below may NOT be sufficient separation for crop safety.
  • If the entire N needs are to be applied, the side band should be at least 2" from the seed row for solution or dry fertilizer and at least 2-3 inches from the seed row for anhydrous ammonia. If the spring remains dry and side-banding causes high disturbance of the soil, seedbed quality and germination may suffer.
  • Mid-row banding the N between every second row at seeding maintains the greatest degree of seed safety. Less soil disturbance and hence more moisture retention would be achieved with a disk type mid-row bander unit compared to a shank-type.
 
Soil fertility Considerations when dealing with dry seeding conditions
Again, research is indicating that 1" x 1" separation may endanger crop safety. To reduce risk, 2" of separation is recommended, and greater than 2" for anhydrous ammonia. Mid row banding is identified as being the best application method for seed safety.
Guidelines for Safely Applying Fertilizer with Seed - Manitoba Agriculture
from May 2004 report
  • Anhydrous ammonia cannot be placed with seed, however, in recent years equipment has been modified to allow anhydrous ammonia to be placed at seeding time in a band or other arrangement, separated from the seed.
  • The anhydrous ammonia must be separated from the seed by at least 2 to 3 in. and be placed below and to the side of the seed, or to the side of the seed. It should not be applied directly below or above the seed.
  • The anhydrous ammonia reaction zone with the soil is pear-shaped. The anhydrous ammonia tends to follow the furrow upward, so attempts at placing it beneath the seed will likely lead to seed damage.
  • In liquid nitrogen (28-0-0) half of the nitrogen is in the form of urea and the other half is in the form of ammonium nitrate. Safe rates of seed-placed N as liquid nitrogen are only slightly higher than for urea.
  • The main phosphorus fertilizer used in Western Canada is monoammonium phosphate (NH4H2PO4) with various analyses such as 12-51-0 and 12-52-0. Monoammonium phosphate has a low salt index and does not release much ammonium, so it has a relatively low toxicity to seedlings.
 
 
Though this report discusses seed-placed fertilizer, it still explains the effects of various nitrogen fertilizers to the seed. Anhydrous must not come into contact with the seed at all. UAN (liquid nitrogen) has half of its N in the form of urea, but still is almost as dangerous to the seed as urea. This is due to the fact that the salt index rating of UAN is almost as high as dry urea. Phosphate (12-51-0) is shown to be relatively low in toxicity, but still must be used in the recommended rates.
Fundamental Issue of Side-banding Systems
Each side-banding system developed (double shoot boots, paired row openers, dual knife systems) and all of the variations under each system were released to the market in the attempt to address the issues of the previous side-banding system. Each claimed to have the new correct seed-to-fertilizer separation, and design to minimize seedbed disruption. But each of these side-banding systems build on legacy of the initial and incorrect assumption, that 1 inch vertical by 1 inch horizontal separation was safe.
Mid Row Banding Proven One-Pass Seeding System
For over 10 years, Bourgault Seeding Systems with Mid Row Banders® have been providing farmers with a low-risk, highly efficient method of one-pass seeding. Unlike side-banding, the Mid Row Bander® system works in a wide range of soil and moisture conditions to maintain a good seedbed while at the same time placing the nitrogen fertilizer in the ideal location.

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