European producers have long been testing low- disturbance, shallow-injection manure application systems for growing crops to reduce nutrient loss and help control odor, which opens up a valuable application window in the spring.
Ontario pork producer Jake Kraayenbrink was so impressed with European results that he set out to replicate those findings in trials on his farm near Moorefield, Ontario.
So far, Kraayenbrink’s results have been mixed. In April, he applied 5,000 gal./acre of manure to 3-in.-tall winter wheat. The manure from a sow gestation barn was injected into 1-in.-deep slots in the soil every 7.5 in. using a Veenhuis disc injector. But he soon realized that his tank was too small to hold enough manure to make a complete pass across the field. That meant he had to stop and refill the tank too often.
“I did about 10 acres like that,” he says. “I went, ‘boy oh boy, this doesn’t look very good.’”
For the next 10-acre field of wheat, he switched from sow manure to finishing pig manure and went back to broadcasting it the old-fashioned way.
Since the nutrient levels in finishing manure are three times higher than that contained in sow manure, Kraayenbrink was able to achieve the fertility levels he wanted with a 2,500-gal./acre rate.
Applying manure in-crop had a positive impact on production. Wheat yields from the field where finishing manure was broadcast averaged 2.7 tons/acre compared to the field with shallow-injection application of sow manure that came in at 3.1 tons/acre.
Kraayenbrink credits the half-ton-per-acre yield advantage to the fact that the manure was injected closer to the root system, plus the application timing gave a boost to the wheat just when it needed it most.
“I think that by injecting that manure 1 in. into the soil, it’s just that much closer for the roots of the plant to get into,” he says.
Unfortunately, finishing manure wasn’t injected in another wheat field as a control to make sure it was the injection that made the difference.
Still, the findings confirm what he’d seen in wheat and hay fields in Europe. But it is still too early to tell how shallow injection performed on his soybean and corn fields.
Kraayenbrink worried that the high salt concentration of manure applied broadcast right on the soybean plant might kill it. It looked like it had for a while, but he says the beans “really bushed out” later.
Another benefit to shallow injection is that the liquid manure doesn’t have a chance to evaporate. “It stays with the plant, which is a real bonus, especially with the drought this year,” he says.
The Veenhuis applicator worked fairly well, Kraayenbrink says, but it will require some adjustments. The biggest change may be to increase the size of the low-clearance discs so they don’t plug up and rip out corn when stones get caught in them.
Kraayenbrink notes he’s also had some damage to the discs from hitting rocks. “The discs will need to be spring-loaded so rocks don’t hurt it as much,” he says.
Sam Bradshaw, an environmental specialist with the Ontario Pork Industry Council, says producers generally have done a good job of keeping manure in the soil and out of the waterways since the nutrient management act came into effect in the early ’90s. The government inspects about 10 to 15% of farms each year; 90% of inspected farms last year got a rating of higher than 70% on their environmental report cards, he notes.
In Bradshaw’s opinion, Kraayenbrink is a true leader, always experimenting and researching. His low-disturbance technology project for in-crop application of liquid hog manure qualified for a $50,000 grant funded through the farm innovation program (FIP), a federal-provincial program open to non-supply managed farm organizations such as Ontario Pork, which supports innovation and encourages commercialization of research.
It is Kraayenbrink’s second FIP project, and his second collaboration with Bradshaw, who administers the program for Ontario Pork. Kraayenbrink’s first project was a system to reduce tire pressure and compaction, which is now commercially available (see
Bradshaw credits Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA) researchers Greg Stewart, Christine Brown and Bonnie Ball-Coelho for their technical support, which helped bring the project to fruition. Unfortunately, it sounds like Kraayenbrink will be on his own to continue working on the shallow-injection project. “The FIP program is winding down,” Bradshaw says. “We’re hoping they’ll restart the program, as it has been very effective.”
Suzanne Deutsch is a freelance writer from Quebec, Canada.