Farmers work hard to maximize fertilizer applications, both for economic and environmental reasons. Making sure all that money spent in fertilizer gets turned into crop — not lost as greenhouse gas emissions — is a key concept in today’s farming practices.
“We want to make sure a producer is realizing value from every gram of fertilizer that he or she puts into the soil,” says Gregory Sekulic, of the Canola Council of Canada. It doesn’t make a lot of sense to spend a lot of money on fertilizer that would then be subject to losses through run-off, leaching, or gassing off (also known as volatilization).
“We can measure both the carbon and greenhouse gas equivalent footprints coming off of a tonne of canola, and we’ve actually built our best management practices around maximizing economic profit in canola,” Sekulic adds.
The easiest way to achieve this is to make sure fertilizer is never left unprotected on a soil surface. “Every fertilizer application we make we want to be protected somehow, either through a treatment or a coating, or with soil,” says Sekulic.
Fertilizer applications are most efficient when they’re covered or sealed by a couple inches of moist soil, put where crops can access them, and where weeds can’t access them. Canola Council of Canada’s best recommendation for this, are to apply at the time of seeding and side-banding beneath the seed level. The research behind this goes back to the 70s, and has very solid results.
There are options for when the fertilizer can’t be incorporated into the soil right away, though — like for fall applications before freeze-up.
Fertilizer should never be applied to snow-covered soil. “Especially if the ground beneath it is frozen, what we would see is either run-off in the spring or volatilization in the spring as the snow melts before the soil thaws,” says Sekulic.
Another reason why the Canola Council prefers spring applications for fertilizer is because a lot of nitrogen losses don’t necessarily happen over winter or at the time of application, they happen in heavily saturated soils in spring, before the time of seeding.
Losses over 15 per cent over winter, especially with broadcast applications that are left unprotected, aren’t uncommon. Fall fertilizer pricing might the reason for a lot of the fall fertilizer practices, but keeping 10 to 15 per cent of the fertilizer dollar from gassing off (volatilization) or running off, will leave canola producers ahead, says Sekulic.
Check out the full conversation between Gregory Sekulic, and RealAgriculture’s Kara Oosterhuis, below: