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Bruce family, Alford SA

Keeping pressure on brome grass with HWSC

Brothers Gary, Paul and Bronte Bruce farm at Alford on the Yorke Peninsula, SA have used harvest weed seed capture as an important tool in their weed management program to bring down grass weed numbers in their continuous cropping business.

For the last 15 to 20 years the Bruce family has followed a 3-year rotation of wheat – barley – legume, having exchanged field peas for lentils in the legume phase in recent years. They found that producing export hay on grassy paddocks was a very effective way to manage grass weed seedbank, to the point where they had only one paddock of hay in 2016 and no hay in 2017.

Gary Bruce, together with the family’s agronomist Chris Davey, YP-AG sets out a plan for the season, including our weed management program, with different strategies used depending on whether there is a wet or a dry start.

“Hay production is hard work and now that we don’t have much of a grass weed problem we are taking hay out of the rotation for a while,” says Gary. “The hard work was certainly worth it in terms of regaining control over herbicide resistant weeds on the farm. Now we’d like to keep more crop residue on the paddocks to improve the hardsetting nature of the soil here.”

Having used a chaff cart for many years, the Bruce’s were well aware of the benefits of capturing weed seed in the chaff stream but Gary was very interested to hear HWSC advocate and WA grower, Ray Harrington, speak at a field day about chaff lining. In 2017 harvest they used chaff line chutes on two headers for the first time. As usual they learnt a lot in their first harvest and have plans to make even better use of the system this season.

Gary is very aware of the fact that there is very limited research on the long-term impact of chaff lining on weed management.

“Our farm is partially set up for controlled traffic with 12 m and 36 m gear so the chaff line ends up on a spray track every third run,” he says. “We found starting the harvester on a spray track at the edge makes the best use of the wheeltracks. If we go to a full CTF system we will probably change to using a chaff deck system but the chaff lining chute is certainly a cheap and effective way to confine weeds to a small area of the paddock while also retaining the stubble.”

Gary’s farm is partially set up for controlled traffic with 12 m and 36 m gear so the chaff line ends up on a spray track every third run. So far they have found using the chaff lining chute is a cheap and effective way to confine weeds to a small area of the paddock while also retaining the stubble.

HWSC and late germination

Brome grass is the most problematic weed on the Bruce’s farm with limited options for control in the cereal phase. There are limited chemical control options to kill early germinating brome grass before seeding and so Gary relies on HWSC to take care of late germinating cohorts. They recognise that hay making has played an important part in keeping this weed in check and acknowledge this could be more difficult if they get out of hay production altogether.

All crops are sown to achieve greatest crop competition possible using 25 cm row spacing and cultivars that are well suited to the different soil types. Two-thirds of the farm is inter-row sown while paddocks with hardsetting topsoil generally follow the same furrow as the previous year. As the soil improves through increased residue retention Gary hopes most of the farm will eventually be sown in the inter-row.

Generally they find, Scepter wheat yields better than Mace, Compass barley produces the most straw, PBA Bolt lentils give salt and boron tolerance where it’s needed and PBA Hurricane lentils offer Group B herbicide tolerance.

“Early in April we usually speak with our agronomist, Chris Davey, about a plan for the season, including our weed management program,” says Gary. “For example, wet and dry starts need different strategies such as ensuring there is sufficient moisture to activate metribuzin and propyzamide before sowing lentils. We have also experienced more summer rainfall recently and often need to do two sprays for summer weed control.”

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Ryegrass management in the High Rainfall Zone – What have we learnt?

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Rod Birch on how the Big 6 is keeping weeds at bay at Catalina Farms

Catalina Farms is approximately 13,000 ha of 100% cropping, with 65% wheat, with the other 35% comprising of 20% canola and 15% lupins. The longterm rainfall is about 330ml per year and around 250-280ml of growing season rainfall.
Taking on a new property usually has its challenges, but there can be upsides too. Some of the challenges at Koobabbie were related to the fact it had been a livestock property and cropping machinery had never having been run through it. However, Rod explained that they have had some great news about the herbicides they are able to use.
Through the University of Western Australia’s resistance testing service, run by Dr Roberto Busi at AHRI, they found out some older chemistries were still effective, which was a pleasant surprise. Daniel Birch explains below in the Regional Update Podcast what they found out and how they used this information in their planning.

Video breakdown

1:10 Crop rotations – Rod’s favourite rotation is Lupins – wheat – canola – wheat. It provides a lot of diversity for Modes of Action, as well as allows for nitrogen to go back into the soil through the lupin phase.
2:10 Crop Competition – the Birches are big fans of crop competition and it’s an essential part of their approach to controlling weeds.
3:00 Double knock – conditions haven’t been suitable for a double knock since 2016, but when the opportunity arises, it’s an important tool.
4:21 Mix and rotate herbicides – the crop rotations used at Catalina allow for really diverse chemical groups to be used, which is a great tactic to keep resistance at bay.
5:52 Stopping weed seed set – the Birches are trying to eliminate as many weeds in the crop as possible. Crop topping is a tool that they employ, as well as late spraying where necessary.
6:49 Harvest weed seed control – seed destruction is on the horizon at Catalina, but logistically has been a bit tricky.
7:21 Acquiring Koobabbie – it has been exciting for the Birches to be able to introduce more diverse rotations. They’ve been able to use Modes of Action which have never been used before.
9:48 Soil amelioration  – liming has been a really beneficial tool for Catalina Farms. They also put out pot ash and gypsum. Deep ripping has also been a great tool to remove the compaction layer.
11:29 Big 6 benefits  – controlling weeds is such an important strategy at Catalina Farms. Rod Birch said “We’ll never have a ceasefire on the war on weeds!”.



WeedSmart Week Forum Day Videos

List of videos

Interviews with the Esperance Pioneers. Chair: Lisa Mayer, interviewing Neil Wandel & Theo Oorschot
Rotating buys you Time, mixing buys you shots
Efficacious use of the new pre-ems, Brent Pritchard
Delivering regionally focused research
Crop competition in wheat and canola, Hugh Beckie
Summer weed control
Strategies for control of ryegrass, marshmallow, fleabane, portulaca, Greg Warren
Farmer Experience
Rotations to stop seed set and preserve chemistry, Tom Longmire
Soil Amelioration, Tom Edwards
Crop competition: Reduced row spacing, higher seeding rates, east-west sowing, precision seed placement & competitive varieties, Theo Oorschot
Farmer Experience – Utilising crop competition strategies and the Big 6, Mic Fels
Weed control – farmer systems discussion panel – Chair: Peter Newman, with Mark Wandel and Laura Bennett
What’s next in spray technology? Andrew Messina
What’s next in spray technology 2? Guillaume Jourdain
Innovation Panel – Chair: Ben White, with Guillaume Jourdain, Andrew Messina
Stacking the Big 6 in farming systems in WA presented by Greg Condon, with Peter Newman


Ryegrass management in the High Rainfall Zone – What have we learnt?

This webinar was hosted by Jana Dixon, WeedSmart’s High Rainfall Zone extension agronomist.

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