TARGETING Low Canola Seeding Rates

If you are a canola grower, high seed cost is a major input expense for your operation. To control these costs you go to great lengths to set your seeding rate and thoroughly calibrate your seeder to make certain that you do not over apply.
You also check over the performance of the drill and monitor your operating speed to ensure seed placement is accurate. Because every dollar of that precious canola seed counts you are focused on doing a great job of seeding it and monitoring the crop’s progress throughout the growing season.

There are things that you can control in your farming operation and things that you cannot; with the amount of rainfall being one of those things that you cannot. In 2019, there were many areas that received their first substantial rainfall in the latter part of June, or even later. Many producers experienced poor and delayed emergence even though the seeding operation was carried out as planned. The variance in emergence from hill tops to low spots resulted in many fields having 2, 3 or more “different” crops growing within the same field. These late emerging and poor developing crops led to a later harvest and in many cases, increased costs and reduced revenues. The primary question here being - was the delayed emergence a result of limited moisture only, or was there a combined effect of limited moisture and fertilizer toxicity / desiccation?
This past season, the Bourgault Agronomy Team had the opportunity to explore this question first hand. Various canola trials were designed comparing application rates, fertilizer placements and seeding systems. Our large scale trials and regular production crops suffered under the same ill effects as other producers. Thus, the findings from the 2019 trials provided some good insight into which seeding system and practices will achieve the best results possible in challenging conditions.
Trials were conducted with two machines and three configurations:

Unit 1
A 3320 on 10" spacing equipped with the Mid Row Bander (MRB) application system
Unit 2
A dual-shank side-banding system on 12" spacing equipped with the MRB application system.
This unit was capable of triple-shooting using MRBs or double-shooting placing all the fertilizer in the side-band.
Fertility rates in pounds of nutrients:
  • Nitrogen – 140 lbs/acre
  • Phosphate – 50 lbs/acre
  • Sulphur – 30 lbs/acre
  • Potash – 15 lbs/acre
Canola seed rate – 4.6 lbs/acre

Conditions during May 28th seeding date:
At the time of seeding, there was low soil moisture with very little appreciable moisture from the time of snow melt until June 15th when the first notable rainfall occurred.
Comparison Plant Stands in Canola - 2019
3320 & MRBs: Emergence results with the 3320 were the highest. Phosphate was placed in a common split row operation with 15 lbs of phosphate in the seed row and 35 lbs placed in mid row. All of the nitrogen, potash and sulphur was placed mid row.
Dual-Knife, no MRBs: Results indicate that emergence was statistically lower than the 3320. In fact, the dual knife produced less than half the emergence of the 3320! The dual-shank unit was configured in a typical double shoot configuration, with all of the fertilizer requirements (N, P, K, S) in the side-band.
Dual-Knife & MRBs: The triple-shoot system used the same dual-shank seed drill as in the previous test, with all of the phosphate directed to the side-band and all of the nitrogen, potash and sulphur placed in the mid row band. Emergence results were statistically better compared to when nutrients were placed in the side-band.

When comparing the typical dual-shank arrangement (where the N, K and S are placed in the side-band) to the triple-shoot arrangement (where the N, K and S are placed in the mid row), it is evident that fertilizer placement is extremely important. Since all of the other factors were the same between the two trials, it is reasonable to conclude that the benefits found with the triple-shoot arrangement were due to reduced N and S toxicity and/or desiccation levels on the seed row. Mixing of the seed and fertilizer may also be a contributing factor, however, these trials were on rather forgiving flow-able soil. This data is in line with dual-shank manufacturer’s public recommendation to ensure seed safety in dry conditions, by reducing the total amount of fertilizer placed in the side-band.

Farms that address input costs by reducing canola seeding rates must be extremely diligent in their understanding of how fertilizer placement and moisture conditions affect germination. Minimizing seed mortality in dry conditions becomes paramount to achieving a plant stand that will maximize yield. A 3320 with Mid Row Banders moves the toxic fertilizer source to a safe distance from the seed, maintains seedbed integrity, minimizes soil disturbance and provides packing directly over the seed to conserve available moisture. The emergence differences documented in the Bourgault 2019 trials were statistically better with the 3320 and triple shoot systems, achieving more than twice the plant emergence levels as compared to the dual shank system! If you are targeting low canola seeding rates you need to make every precious canola seed count. That is why it is paramount to avoid seeding systems that contribute to low emergence from fertilizer damage. A Bourgault seeding system with MRBs allows you to reduce seed costs and avoid fertilizer damage, even in challenging conditions. In addition, achieving even and healthy seed germination will support even maturity, superior grade and higher yields.
The results of this study show that even though you cannot control the weather, your choice of the seeding system and practice will minimize your risk of poor emergence due to dry conditions. You strive to control what you can in order to make your farm profitable each year. Bourgault is there to provide the best equipment and practices to help you achieve that control and place your farm in a much improved position when the weather is not cooperative.
Bourgault - Designing Equipment Around Agronomy