Controlled Traffic Farming is in simple terms driving your heavy vehicles on the same wheel
tracks every time you're in the paddock.
In Australia's southeastern grain growing region Controlled Traffic Farming has been
widely adopted in high and medium rainfall zones but not so much in low rainfall zones.
Something the zone's regional cropping solutions network saw as an issue.
And the question arose is that an opportunity the low rainfall farmers were missing out
on.
Nigel Wilhelm a senior scientist with SARDI specialises in sustainable farming systems
and as a result of the RCSN's deliberations, he was appointed lead scientist for a Grains
Research and Development Corporation invested project to investigate Controlled Traffic
Farming in Low Rainfall Zones.
We surveyed the farmers at the start of the project.
I guess some of the answers we got back is, it doesn't work with our big gear, our farms
and soil types are too diverse to make it happen, not all our paddocks are regular so
we can't drive in straight lines and so it's not going to work as well.
And they are all factors but it doesn't necessarily stop you from using controlled traffic farming.
Wade Nickolls from South Australia's southern Mallee cautiously moved into controlled traffic
15 years ago and shares some of those reservations revealed by the survey.
We'd like to get as far as we can with controlled traffic but we're probably never going to
get to quite 100% we still do a lot of hay and with our bigger machinery and stuff its
hard to get everything to line up perfectly.
Robert Pocock is a 5th generation Mallee farmer 20k north west of Lameroo.
Like Wade Nickolls he introduced controlled traffic over a number of years.
We haven't been in a rush to do it, its got to fit with our cash flow obviously and I
think that will be the key to the success of the controlled traffic is to not let it
takeover the bank account.
Concerns such as these are real, however Controlled Traffic Farming or CTF can be partially adopted
and slowly, according to Nigel Wilhelm.
It is a system that you can implement incrementally and take your time at it and I suppose we
need to acknowledge that a lot of farmers are partially in controlled traffic now anyhow
with auto steer and attempting to match boom width and seeder width so that starts confining
the heavy traffic into constricted parts of the paddock anyhow.
On many farms wheel tracks can cover between 40 to 70 percent of a paddock.
So by driving on the same wheel tracks or tramlines the trafficked area can be reduced
down to 10 or 15 percent.
To measure the impact of traffic on crop production this research project took two approaches
to field trials.
One looked at how crop production was impacted by wheel traffic on commercial scale paddocks
and the other saw a series of farm plot trials established with and without wheel tracks.
The idea behind that was if we could document how much crop production is affected by heavy
trafficking then the flip side of Controlled Traffic is that those penalties should be
foregone or recovered in a Controlled Traffic Farming system because you're not driving
heavy vehicles on the cropped area any more.
At a commercial paddock scale the crop production difference between trafficked and non-trafficked
was 4 percent.
What's the 4 percent mean, it means that if you move from the current system of a semi-controlled
traffic, which is what most farmers are in now because they are on auto steer, to a full
controlled traffic system which means they reduce their footprint on the paddock by a
half to two thirds we'd expect overall they might get 4 percent increase in crop production
across their farm.
What the research also said about that average of 4 percent movement in crop productivity
in a Low Rainfall Zone was that it could vary.
On deep sandy soils the expected benefit could be much higher.
Down on the flats that 4 percent might drop back to zero according to Nigel Wilhelm.
Does that mean controlled traffic farming is a waste of time?
It still isn't because there's still that operational side.
There maybe times when you can get on the paddock early because you've got compacted
roadways which means you might get better weed control or you might be able to harvest
a crop before another rainfall event damages it.
Those sort of occasional things can happen cause you've got that setup in place.
Wade Nickolls will take the small benefits because multiplied across a big area they
become significant savings.
just being able to get back on your tracks after rainfall events quicker than usual,
small gains in using a little bit less fuel.
I mean its all good for us cost savings that we can you know over a big program can actually
add up to a substantial amount at the end of the day.
Small gains such as a 4 percent lift in crop production were a consistent finding for the
research team.
In low rainfall zones benefits from CTF were similar to those in medium and high rainfall
zones only smaller.
That's partly because crop productions levels are a lot lower so the returns per hectare
tend to be lower.
What the project's grower survey also identified is there's difference in what is understood
by Controlled Traffic Farming.
Certainly people believe controlled traffic farming is about bare wheel tracks, unless
you've got bare wheel tracks you're not fully controlled traffic.
That's not the definition we use.
We're quite happy to have and in the low rainfall faming environment we'd expect you to have
sown wheel tracks because erosion is certainly an issue on those wheel tracks and that does
undermine some of the benefits of controlled traffic because you are cultivating those
roadways which you are trying to compact for fuel efficiency issues.
But that's a compromise we need to accept in low rainfall farming environments.
Erosion of tramlines is a challenge Robert Pocock has faced.
On the sandy soils you know the wind loves to get into it and if we're lucky enough to
get a good rain and a storm you know water can get into them as well so.
And like many in the Mallee low rainfall zone their farming business is a mixed enterprise,
growing legume pastures and lucerne hay for livestock.
A farming system seen as unsuitable for the adoption of controlled traffic.
We're cutting hay on an angle to the way its sown.
Hay balers are coming in they're contractors so you know there's no-way of having that
fit on a tramline.
Moving hay out of the paddock its got to be done efficiently you know its quite challenging.
What Nigel Wilhelm wants growers to consider is that in a low rainfall zone modifying their
approach to a Controlled Traffic Farming system is OK.
So another compromise that farmers will face when they're in controlled traffic is the
issue of growing hay an increasingly handy option when you are managing grassy weeds
etc.
If you want to cross sow that to get a better header row standing up for hay again that's
not something you should be doing in controlled traffic its an exception you might have to
make, its another compromise.
Perhaps the biggest comprise of all is how to look at upgrading machinery, a cost many
farmers saw as a deal breaker.
I guess our response is that's not the model we have in mind.
Its not going out and buying a new suite of machinery that matches axil widths and swath
widths its taking it incrementally as you suggested and every time you change your machinery
which you're going to do anyhow then you change it to a setup which will fit into a controlled
traffic system.
an example with some of the modifications we've made and how we've got into controlled
traffic have been changing axils on chaser bins and jus lining machinery widths up as
we've gone.
Obviously cotton reels on tractor, just an easy quick way to take the wheel out to where
we need to be, bring the back wheels out as well.
The reason the Controlled Traffic Farming in Low Rainfall Zones project was initiated
in 2014 was to answer the question was this an opportunity growers were missing out on.
When the project was brought to a close mid way through 2019 another grower survey was
conducted.
The findings from that survey is that there's a lot of interest, a lot of awareness now
of controlled traffic and a lot of the farmers who responded were confident they knew more
about controlled traffic farming then they did previously and felt they were in a position
to make a decision about it and that decision might be its not for me but at least it's
a better informed one according to the survey so we're quite pleased to hear those results.
Although the research targeted southeastern Australia the findings will have application
in other low rainfall zones where soil types are similar.
And a user guide has been produced as well.
So its going to capture the findings from the project and it will be a place that farmers
and advisors can go to and say what are the pros and cons.
There's 8 or 10 case studies in that of famers that have put it in place and what their experiences
are and there are some guidelines about if you were to go controlled traffic farming
what are the major principles you want to keep in mind as you implement across that
farm business.