- Growers: Adam and Rebecca Smith; Richard and Di Smith
- Location: East Beverley, Western Australia
- Size: 2200 hectares
- Soil types: Sandy loam over gravel with some heavier soils
- Enterprise: continuous cropping for the past five years
- Crops: barley, canola and lupins
- Average annual rainfall: 380 millimetres, 280mm (growing season)
- Soil pH: zero to 10 centimetres: 4.8 to 6.5; 10 to 30cm: 4.4 to 6.0
When Western Australian grower Adam Smith first considered implementing controlled-traffic farming (CTF) principles on his property, he did so in an attempt to reduce trafficability issues in paddocks during wet winters.
The property is located at East Beverley, so wet winters can mean messy paddocks - or even a complete inability to get machines on to paddocks at critical times of the season.
"With machines increasing in weight, we were making a mess in the paddocks and spending critical time getting bogged," Adam says.
Despite making the decision to commit to CTF principles in 2014, this is the first season all the machines in the business are fully matched on three-metre wheel centres.
While this strategy has reduced trafficability problems, Adam has seen a range of other benefits.
"We didn't initially consider it (CTF) from the point of view of soil compaction or protection of any deep-ripping, since the majority of our soils (loam over gravel) don't seem to respond as well to deep-ripping as a traditional sandplain soil type," Adam says.
"But there have been numerous other benefits to the business, not least of which is the ease of putting seasonal employees on standard wheel tracks to make seeding, spraying and harvesting much simpler."
With machines increasing in weight, we were making a mess in the paddocks and spending critical time getting bogged.
Adam is very interested to look at the yield data after this first season to see how the numbers have changed now that all vehicles are lining up in the paddock.
"I don't yet have the data to prove the worth of CTF on paper, but last year was the first year where we saw a visual difference in the crops, particularly in the canola," he says.
"I could see significantly less flowers on the canola in the dual-wheel tracks, when compared to the untouched soil, so there would have been a definite yield response."
I don't yet have the data to prove the worth of CTF on paper, but last year was the first year where we saw a visual difference in the crops, particularly in the canola.
Principles in practice
Adam first learnt about CTF principles at university, but didn't seriously consider the idea until he and his wife Rebecca had spent several years back on the farm.
Once they had made the decision to follow the path towards CTF, all new machinery purchases were based on their 12.1m seeder bar.
The first upgrade in 2015, a self-propelled sprayer, was 36.6m, which then required a nozzle on each end to be shut-off to become a multiple of 12.1m to match the seeder bar.
Their harvester was upgraded next, to 12.1m, and the auger has been extended to allow all chaser bins to stay on the wheel tracks. The purchase at the end of last season of a tracked seeding tractor was the final piece to complete the Smiths' CTF puzzle.
GRDC has invested in production of a grower case study booklet that contains tips and tools from a range of WA CTF croppers and researchers for those interested in, or who use, CTF practices.
Apart from managing machinery movements in the paddock during wet periods, Adam says there have been many business benefits from CTF, as he outlines below.
Without permanent wheel tracks that are evident to the driver, lining the seeder up at each turn can be difficult in tighter country.
"Now, when a driver is turning a machine around and picking up their GPS line, they can also see the visual line down the paddock, in and out of crop, so there isn't this wiggle at the start of the GPS run, which is a really basic thing that I never thought of at the time," Adam says.
"The spreader driver can now clearly see where they are supposed to drive, and they have the correct GPS paddock selected before starting."
2. Accurate spraying
Adam says before CTF, weeds were more obvious where the sprayer turned around at the end of each run and didn't always line up correctly.
"If the line wasn't quite right, the boom could flick left and right which changed the spray rates and impacted on the weeds in this area," he says.
"But using CTF, everything is completely lined up and we don't have this problem any more.
"Weeds used to be a huge battle for us but now they are a minor factor."
Adam says the untouched areas of the paddocks were visually better crops than those in the wheel tracks. After this season, now that all his machinery lines up, he hopes to have a better understanding of the data behind this visual impression.
4. Soil amelioration
While Adam hasn't seen any yield benefit yet in his deep-ripping trials, a major yield constraint for the business is water repellent soils.
To combat this, last season Adam tested a Plozza - or one-way - Plough, which buried the repellent topsoil, over a 20-hectare on-farm trial.
Results from the trial showed a 900 kilogram per hectare response. Because of this positive yield increase, he plans to plough up to 15 per cent of his program each year for the next five or six years. CTF will protect his investment in this amelioration treatment.
As a result of the CTF system, the Smiths now have a chaff deck system to manage harvest weed seeds and all chaff lines are left on the tramlines, which Adam says has meant a significant reduction in weeds across his paddocks and reduces his reliance on burning in the busy autumn period.
Weeds used to be a huge battle for us but now they are a minor factor.
Adam's wife Rebecca is a research agronomist, so the couple is committed to grains research through numerous trials on their property, all of which are much easier to manage and monitor now because of CTF.
"We would regularly have anywhere between three and six trials on our farm in any year, and now that we use CTF principles, we can easily track the responses and the results through the header yield monitor," Adam says.
"I can also lay out our own farm trials far more accurately."
During the planning phase in 2014, Adam says he based all machinery measurements on the width of his seeder bar (12.1m). Their seeding machine, while very reliable, is quite old and will need to be upgraded in the near future.
"In hindsight, I think I should have gone with a standard metric measurement, rather than using 12.1m which is halfway between the two popular widths, because it doesn't quite match any new seeders off the shelf at 12m or 12.2m," he says.
"Dad and our workman are great at maintaining this seeding machine, so for the moment the system works well, but since it's an older piece of equipment it will need to be upgraded at some point, and quite possibly it could be difficult to find a new machine based on that custom width."
Adam's advice to anyone considering moving towards a complete CTF system is to upgrade the seeding bar first, if possible, and base all other machines on that.
He says one of the most talked about issues on social media regarding the adoption of CTF is the difference between metric and imperial measurements.
"Since a lot of machinery comes from the United States and Canada, we have a lot of machinery here in Australia that is still measured in feet," he says.
"So, the big question really is, do you go imperial measurements, or base everything on a metric system?"
Adam says he won't know how important this question is until he has researched new seeding equipment.
The other major challenge is the length of time it takes for a business to fully transfer over to a CTF system.
Adam began the process in 2014 and it has taken five years to have all the machinery and wheels lined up.
"You have to meticulously plan your future machinery purchases. Getting the widths the same is relatively simple but getting all machines' and implements' wheel spacings the same takes more time and investment. This is a long-term commitment."
Planning the key
Department of Primary Industries and Regional Development (DPIRD) research officer Wayne Parker agrees planning is the key to the success of any CTF system.
He says CTF uptake in WA has been relatively slow, despite the many documented and proven benefits, with only 22 per cent of growers across the state considered fully guided by CTF principles.
This figure was determined in 2016 and early figures from a 2019 survey indicate there has been growth of adoption in WA during the past two years.
"We understand why there has been a slow uptake of CTF - because it requires significant fiscal investment in machinery," Mr Parker says.
"This can't happen in one season, however, there has been a positive shift in the levels of CTF adoption in the west in recent times.
"What is required is a change of mindset: an understanding of the yield damage caused through compaction, taking ownership of the problem, then developing a responsible plan to move to CTF."
Mr Parker encourages growers interested in moving towards a CTF system to participate in the numerous social media forums now available on the subject.
"Growers learn from other growers, and there are now many examples on social media demonstrating how individual growers have utilised the benefits of CTF principles," he says.
What is required is a change of mindset: an understanding of the yield damage caused through compaction, taking ownership of the problem, then developing a responsible plan to move to CTF.
Mr Parker says there will continue to be face-to-face learning opportunities for growers about implementing CTF strategies on-farm, such as recent the National Controlled Traffic Farming Conference in Ballarat, Victoria, which attracted growers, researchers and advisers from across the country and the world.
Adam was one of 10 young growers who participated in a Western Australian No-Tillage Farmers Association (WANTFA) tour in the lead-up to the National CTF Conference in February.
WANTFA chairman Clint Della Bosca and WANTFA vice-chair Trevor Syme led the group of growers on the GRDC-invested tour, visiting farming businesses in South Australia and Victoria that have implemented some level of CTF strategies.
More information: Adam Smith, firstname.lastname@example.org; Wayne Parker, email@example.com