It won’t surprise you to read that very little ground got anhydrous ammonia (NH3) applications this fall. In my territory in Manitoba’s Parkland region, the farms that put some down maybe covered two thirds of their acres. Across the province, maybe 15-20% of acres got covered, and in the Dauphin area they didn’t even turn a wheel.
The good news is that fertilizer prices are down substantially versus last year. This has me looking ahead to spring, when we’ll see our next opportunity to make up for lost time and missing nitrogen. As I see it, you have one (or more) of five application methods to choose from when the snow melts:
- Floating/spreading on the soil surface followed by incorporation;
- Mid-row banding;
- Dribble banding; or
- Foliar application.
Each of these has its benefits and drawbacks, some more obvious than others. For example, I would recommend a foliar spray only for top up applications, as applying all the crop nutrient requirements at once would be too harsh for the plants, but dribble banding gets right to the crop and won’t cause injury because it doesn’t cover the whole plant.
A split application might sound attractive, but I don’t typically recommend it because you can experience N losses before seeding and you would only add 50-60% of the crop’s needs after establishment. Splitting fertilizer applications can be a big challenge for large farms, as they also have to fit in herbicide applications in spring. However, it’s something to consider to limit financial risk if you have either excess moisture or drought conditions.
I prefer banding – either mid-row or banding ahead of your seeder. You can add other nutrients (for example: potash and AMS) to the N and band the fertilizer a minimum of 2 inches deep. With enough moisture, roots will naturally grow toward the nutrients and get three nutrients rather than just N when they encounter the band.
The major limiting factor – one we experienced last year – is dryness. I dug down 14 inches on one of my customer’s fields (sandy loam soil) last summer before I ran into moisture. That’s not good news for N, because it needs water to move in the soil.
With these factors in mind, I’ve identified four alternatives to applying straight NH3 or the traditional nitrogen treatments 46-0-0 (urea) and 28-0-0 (UAN) that can help you manage your time and N investment this spring. These methods are also consistent with the 4R approach (right source, right time, right place, right rate).
ESN is a urea granule made up of 44% N, contained within a polymer coating, which is designed to allow it to release over 30-60 days. Do not float or spread this product. It must get down 2 inches into the soil, and you will not want to use it in dry conditions, because the coating will not break down without water (Think of it like your dishwasher detergent capsule.). ProTip: If you buy ahead and store fertilizer on farm, mix 10-20% ESN to keep it dry and flowable.
SuperU is a granule that includes urease nitrification inhibitors infused all the way through so it stays in the soil and protects against volatilization, denitrification, and leaching. This product is a little more costly than some alternatives, but it can be quite effective.
Agrotain Ultra is a liquid urease inhibitor that is applied to urea or UAN and reduces N losses to volatilization especially if you spread urea and work it into the soil, as you likely won’t cover all the granular fertilizer. Volatilization starts within three days and it’s possible to lose 50% of your N investment in 25 days.
YaraVera® Amidas™ (40-0-0-5.5)
This product is newer to me, but it is billed as a replacement for urea and fits well with most crops. It contains N and sulphate S in every granule. The drawback is that it starts to gas off quickly. Banding or mid-row banding at least 2 inches deep will lessen the chance of volatilization.
If you’re not sure what option is a fit for your crops’ needs, your timeline, and/or your budget, contact your nearest Cargill location for more information.
ESN is a registered trademark of Nutrien Ltd. SuperU and Agrotain are registered trademarks of Koch Agronomic Services LLC. YaraVera is a registered trademark and Amidas is a trademark of Yara International.