When you think about compaction, you might think an ounce of prevention is better than a pound of cure. Controlled traffic farming is a system that may be both cure and prevention.
Controlled traffic farming separates crop from traffic zones. “Wheel tracks are confined to specific lanes or tramlines,” Peter Gamache told delegates at Crop Production Week in Saskatoon in January. Gamache heads Controlled Traffic Farming Alberta (CTF Alberta), an on-farm research organization.
Chatting with reporters after his presentation, Gamache said farmers are showing lots of interest in the system, but it’s still early days. He estimated that about 15 Alberta farmers have converted to controlled traffic, at least in part. Producers “have lots of healthy scepticism” about whether it will make sense on their farms, he added.
Controlled traffic is more widely used in Australia, but Gamache told reporters Australians have been at it for 20 years.
“I think the biggest thing is Australia has had their backs against the wall because of climatic conditions,” he said. Much of the adoption in Australia took place during a prolonged drought, he said, and controlled traffic farming performs well during droughts.
So how well does controlled traffic farming work in Alberta? And what are the pros and cons of the system? More work needs to be done, but CTF Alberta is starting to yield answers.
The research so far
CTF Alberta completed a project between 2011 and 2013, and is now into its second three-year project. The project collects data from five co-operating farmers located in various parts of Alberta.
During the first project, farmers implemented controlled traffic on plots ranging from 140 acres to 480 acres. A plot with regular random traffic served as a check. Gamache said they’re now using replicated plots to gather statistically-valid data. The co-operators have also switched most of their acres to controlled traffic in the last few years, although some may still be changing pieces of the system, Gamache said.
Farmers switching to controlled traffic don’t need to stick to small equipment. They can scale up by using ratios. For example, Craig Shaw of Lacombe used a 30-foot combine header, 30-foot seeders and a 120-foot sprayer, according to a CTF Alberta report. Gamache said co-operators’ seed drills range from 30 feet to 80 feet.
One benefit they’ve seen is risk management. Controlled traffic farming systems work well during droughts and excess moisture situations, Gamache said.
And controlled traffic systems give farmers an edge when it comes to completing field operations in a timely manner. Most of the Alberta co-operators said they were able to spray on their tramlines a little earlier than their neighbours, Gamache said.
“The tramlines are packed. They’re hard. They hold traffic.” Gamache added that if they can stay on tramlines, farmers can harvest in “horrendous” conditions, if need be.
Controlled traffic farming is also a good platform for on-farm research. “Pass-to-pass accuracy is phenomenal. The elimination of errors and odd-ball things” such as random field traffic creates better, more reliable data, Gamache said.
The system also makes it easier to do inter-row seeding, Gamache said. Co-operating farmers can then leave taller stubble. By leaving cereal stubble at 16 or 18 inches, Morrin-area farmer Steve Larocque was able to boost harvest speeds from two to 4.2 mph, according to the CTF Alberta report. That stubble also makes the following year’s pea crop easier to harvest, even if it gets nailed by hail.
Farmers have also seen better water infiltration and more even crop maturity, Gamache told delegates.
University of Alberta researchers will be looking at rooting depth, root size, pore space and biological activity in the soil. “All those we would expect to improve,” Gamache said.
Asked whether controlled traffic fields were less likely to develop ruts, Gamache said there probably was a gain in that area with controlled traffic. “But we need to probably have some more variety in weather, too,” he said.
Gamache said most tramlines have held up well, but are now at the stage where they need a tune-up. The tramlines tend to dish and rise in the centre, he explained. How often ruts will need to be fixed will depend on weather, he added.
Drawbacks and unknowns
Australian researchers have noted yield gains in controlled traffic systems. But so far Alberta yields are “kind of flat,” said Gamache. So far they haven’t seen a consistent, real difference between controlled traffic and random traffic plots, he explained.
Gamache hopes that will change.
“We do think that soils take time to repair and some soils may not repair very quickly just by nature of their texture and those kinds of things,” he told reporters. Some soils, such as cracking clay, seem to respond quicker, he added.
In England, farmers are routinely told to do some deep working of their soils while they’re establishing tramlines, Gamache said. He added the Alberta group hasn’t tried it yet, but has talked about it. The layout of a controlled traffic system would lend itself to such an on-farm experiment, he added.
Controlled traffic farming is also a rigid system, Gamache said. Farmers can’t buy machinery without making sure it’s the right size, he said. Sometimes a machine’s working width is less than the manufacturer’s specs, so farmers need to measure.
And for controlled traffic farming to work, farmers can’t deviate from the tramlines. “If you have a lot of custom guys, you’re not likely set up to do this,” said Gamache.
Fields dotted with sloughs, bluffs or other obstacles aren’t ideal, either. “Long straight runs are helpful,” said Gamache.
Gamache said controlled traffic farming has a big learning curve. Co-operating farmers have been doing it for a few years but are still refining their systems, he said.
Weed control on bare tramlines has been a problem in Australia. Alberta farmers are seeing more weeds on their tramlines, too. “There’s less competition. That’s also where we get good seed to soil contact,” Gamache said.
There are also capital investments. Most farmers upgrade to RTK, which is a more precise guidance system than GPS. Farmers might also need to modify existing equipment.