A few of you reading this may be old enough to remember when most seed came in burlap sacks. Farmers had to lift them by hand and manually pour the grain into a drill, which then dropped those kernels two or three feet into the soft ground to be covered over. That made for some pretty gentle grain handling.
Today, however, things are much different. Cereal grains are handled in bulk while canola seed is sold in large-capacity totes, and all of it will end up passing through an auger a couple of times before dropping into the seed tank on an air drill.
After that, it’s blown at a relatively high speed through a seeder’s piping system before coming out an opener. Each stage along that route from the bin to the soil holds a risk of handling damage for seed.
Damaged seed is less likely to germinate. And as growers increasingly target precise plant populations, seeding-rate calculations made without factoring in losses from handling may lead to reduced yields. But how do you find out if your seeder is spitting out damaged seed? Put a sock on it, says Rick Taillieu, grower relations and extension coordinator at the Alberta Canola Producers Commission.
THE FIVE CENT SOLUTION
He’s talking about tying an old sock to the end of a delivery tube on an air seeder and taking a sample of the seed that comes out. Comparing those kernels to seed in the tank, and seed still stored in the bin will provide a good indication whether or not damage is occurring at any step along the way.
“I think it’s a bigger problem than most people realize, because most people don’t check,” says Taillieu. “What happens after we run it up the auger into a truck? What happens after we pass it through a very small auger to get it into the drill, and what happens through the (drill’s) distribution system?”
Taillieu was involved in tests carried out to evaluate those very questions with canola and peas. And, he says, in many cases the results showed handling did cause damage. “If the seed was drier, it was more vulnerable to damage. And depending on how the fan speed was set — and with different drills — we saw different levels of damage.”
When evaluating seed in the trials, some damage wasn’t immediately apparent. “Often times we didn’t realize how severe the damage was until we sent the sample to the seed lab. There were splits in the seed coat you could see under a microscope, which makes them more vulnerable to disease, affects germination, lowers the vigour and a number of other things,” he says.
Fan speed is one of the most critical factors in determining the level of seed damage through a drill. “When it hits the splitter at the bottom of a double-shoot opener, the faster it’s going, the more likely it is to be damaged,” says Taillieu. “That’s where seed quality plays a role, too. When we did (the test) with pea seed and it was really dry, we saw damage. Another farmer we worked with ran a garden hose as he augered his peas to moisturize them. Then we saw basically no reduction in germination.”
On top of the risk of mechanical damage from hitting components in the distribution system, seed may be delivered along with granules of fertilizer in single-shoot applications. That increases the possibility of damage from bumping into other product within the delivery lines. “For guys that are single shooting, they’re putting five pounds of canola through the same tube as 40 pounds of nitrogen,” says Taillieu. “Now the canola is banging into the nitrogen as it’s going through the air system, too.”
“As we try to educate farmers to aim for a targeted plant stand no matter what they’re growing, we need to know if they’re getting it,” he adds. With all the handling of seed between the bin and final placement, it is likely damage will cause some germination rates to fall. “We can chip that germination rate down 10 per cent, and then suddenly you’re not getting the plant stands,” he says.
HOW TO DECREASE DAMAGE
So, what should growers do to minimize or eliminate the problem? First, Taillieu says, they should always begin by planning seeding rates to target a number of plants per square foot. To get it, they need to know the 1,000-seed weight and correct vigour number.
By finding out how much damage occurs as seed is moved from the bin to the ground, a grower
Attaching an old sock to product lines at a drill’s opener will allow producers to take seed samples and check for handling damage.
The seed sample on the right was taken from an opener spout on an air drill. There is noticeable damage from handling compared to the sample on the left, which was taken from the tank on the seed cart.
will at least know how much to boost seeding rates in order to compensate. Or, they can take steps to reduce damage levels by correcting handling procedures or drill settings. Then they can follow up by going into the field and see if they achieved their target plant population.
“Guys need to go out and dig up some plants, like canola, and see if they are all seeded where they aimed for at half an inch.” Checking fields will also allow producers to see if all openers were functioning properly. If a particular seed row shows a consistent problem, a producer can go back to the appropriate opener on a drill to see what the problem is.
As producers take on more land and are pressured to get large acreages seeded in a narrow time window, the temptation to go fast and not check seeding results is pretty strong, notes Taillieu. Because of that, having a second person available during seeding can be a valuable resource. He or she can take the time to follow the seeding operation, check seeding depth at several spots and confirm the drill is performing properly.
And doing a little on-farm research can pay big dividends, he adds. “I’m a huge fan of farmers doing little experiments in their fields, and they don’t have to be complicated.
“For a guy to do a couple of passes down the field a half mile per hour slower is priceless. I can tell you, anecdotally, everyone who tries that ends up going a little slower the next year. If they do that on all their crops, they’ll find out which ones they need to seed slower and which ones are a little more forgiving. For shallow crops like canola, any extra speed is not a good thing, it’s going to cut back on emergence.
“And they can do the same thing with fan speed,” says Taillieu.. “You either learn you’re doing something wrong or what you’re doing is OK.” He adds that it’s tempting to turn up the fan speed when the seeder plugs up and time is of the essence, but that can really cause damage; slow down instead. “Faster ground speeds require more air to deliver the product, creating a compounding negative effect,” he says.
Scott Garvey is machinery editor for Grainews.
Contact him at [email protected]