If you successfully maintained your stored crop in good condition through last winter and this spring, pat yourself on the back: last year’s harvest and storage conditions were about as challenging as they come. Due to terrible weather at harvest across much of the Canadian Prairies, a large percentage of harvested grain went into bins wet or variable last fall, leaving producers fighting for weeks or months to pull it into proper storage condition.
Why it matters: Farmers who are ready for challenging harvest and storage conditions may minimize spoilage risks in the bin.
Grain storage experts and farmers usually agree that canola is one of the most challenging crops to store. The storage experts at the Canola Council of Canada (CCC) had some advice on how farmers might best tackle storing a challenging crop if another difficult harvest season occurs.
The CCC’s first words? If you had trouble getting your crop into good condition last year, know you weren’t alone. While the organization doesn’t have any formal reporting mechanisms for deterioration in storage, losses certainly occurred.
“Based on what we know about safe storage, I don’t think I would be going out on a limb to say we likely had more deterioration last year and this spring,” says CCC’s Manitoba agronomist, Angela Brackenreed.
“Last year’s harvest conditions were incredibly difficult. Producers did their best to manage but really nowhere on the Prairies did we have any significant amount of time through harvest where we could dry with natural drying: we were at less than 10 C or more than 70 per cent relative humidity right through.”
Know what you’re dealing with
As all farmers know, successful storage comes down to managing temperature and moisture. The first step is knowing exactly what you’re dealing with. Last year, many farmers faced something arguably more challenging than a wet crop: they faced significant moisture variation throughout the crop. Poor harvest conditions meant many farmers started and stopped and started harvesting, often switching fields in search of the driest grain. When they did manage to get the crop off, mostly dry fields still often hid wetter spots.
“In years like last year, when you are dealing with rain and snow, you can get a real mixture in your bin. What that means is you think (the grain) is at a certain moisture in the bin, but you’ve got pockets of higher moisture. With canola, spoilage just needs a starting point. Once it gets going, heating can take off very quickly,” says Shawn Senko, CCC’s southern Saskatchewan agronomist.
Also, the starting and stopping of harvest meant grain was harvested and subsequently entered the bin at varying temperatures: another significant risk factor for spoilage.
“The goal with managing canola in storage is to get grain as uniform as possible. When you have layers of different temperatures, that’s when things get really volatile,” says Brackenreed.
Senko’s advice for successful storage in any year — especially a year with challenging conditions — is to be extremely vigilant and proactive both during harvest and storage about temperature variation, moisture levels and potential moisture pockets.
“Last year’s harvest lasted forever. When you’re in the middle of combining, recommendations get pushed because getting grain off is the highest priority. But, you really need to be checking bins. And if you’ve got a break in harvest, you need to be turning them. Every time you auger in and auger out a bin, you’re mixing up pockets and layers, which minimizes opportunities for spoilage.”
Another important factor in spoilage is green seed. Unfortunately, there hasn’t been much research into how varying levels of green seed impact storage time.
“The trouble with storage research is there’s a humongous amount of risk there: you often have to take a large volume of grain to the point of deterioration to get meaningful data, so that’s incredibly expensive,” says Brackenreed. “But, it’s so frustrating not having good research on this. I want to be able to tell producers, ‘at that level of green seed, you need to move it as soon as possible’ or ‘at that level of green seed, you can confidently store for X months.’ As of now, we just don’t have that research.”
While there’s no official research to solidly confirm the correlation between green seed volume and storage time, Brackenreed does have one recommendation.
“I heard a great rule of thumb from a researcher at the University of Manitoba, though he was careful to put a caveat on this advice by saying it was only his personal experience. He said, ‘For every per cent increase in green seed, you need to drop the length of safe storage by five per cent.'”
Grain harvested at higher moisture that couldn’t be dried needs to be cooled significantly to stabilize it. Last year’s unusually cold fall nights meant it was possible to bring the temperature down quickly — a saving grace at the time. Choosing when to turn off a fan is a delicate decision-making process influenced by harvest temperature, outside temperature, moisture readings and the variability within the bulk. As a simple rule, keep fans going until the temperature front has moved through the entire bulk, creating uniformly cold conditions in the bin, ideally below 0 C. Restart the fans to cool again once ambient conditions are significantly cooler than the bulk.
While cool weather in fall brought bins’ temperatures down quickly, an unseasonably cool spring made early-season conditioning difficult, compounding moisture issues for those without supplemental heat.
“Canola needs at least a solid three to five days of optimal conditioning weather to remove the moisture that a lot of producers had this spring, and we just didn’t get that weather,” says Brackenreed. “Some farmers were turning on fans at 15 C, but there just weren’t enough hours. Now you have grain that’s been warmed up but isn’t actually dry, and you’ve got even more of a problem.”
To make matters worse, while early spring temperatures stayed low, the spring sun beating down on grain bins created spring heating before farmers could successfully condition the grain.
Even some farmers with supplemental heat were challenged by the cool spring, as choosing the right timing to turn on that heat proved difficult.
“Some years are just hard,” says Senko. “You can do everything as well as possible and still run into challenges. That’s farming.”
Farmers are an optimistic bunch who bank on the fact that next year will be better. Brackenreed cautions that weather statistics suggest future years may, in fact, have increasingly unreliable weather. As such, she recommends farmers start to look at harvest slightly differently.
“I think we may need to be ready for years like last year more than ever. I wouldn’t want to prescribe anything to farmers, but it’s worth thinking about maybe starting a little earlier with harvest to hedge your bets a little and get that crop off, especially if you invest in capacity to manage it (in the yard).”