Grains Research and Development

Date: 19.01.2015

Seed crusher eliminates need to burn

Author: Nicole Baxter

Harrington Seed Destructor at a glance

Peter Sadler says the best features of the Harrington Seed Destructor (HSD) include:
  • the ability to mechanically deal with ryegrass;
  • the capacity to retain organic matter and keep nutrients rather than burn and destroy them; and
  • being able to complete other jobs instead of windrow burning.
He says the HSD’s less likeable features include:
  • the need for organisation and initial set-up; and
  • the extra fuel required.

After using a Harrington Seed Destructor for the second year running, the Sadler family in Western Australia is able to offer some insights into its effectiveness to other growers keen to replace burning with weed seed destruction

Image of a grower in front of a Harrington Seed Destructor.

PHOTO: Nicole Baxter

For the first time in 20 years, the Sadler family will not have to burn narrow windrows to destroy herbicide-resistant weed seeds.

2014 was the first season Western Australian growers Peter and his son Michael put their Harrington Seed Destructor (HSD) to work across their entire cropping program, which is spread over two farms, one near Wongan Hills and the other near Bindoon.

Peter and Michael bought the HSD in 2013 after seeing a prototype in action three years earlier.

They initially arranged to buy a chaff cart, but cancelled the order after learning a HSD originally built for another grower had not sold.

“Chaff carts are OK, but you’re burning nutrient, so when this HSD came up and we did some research, we decided to buy it,” Peter says.

The HSD, bought for $210,000 from de Bruin Engineering in South Australia, arrived at the Sadlers’ farm near Wongan Hills in late October 2013; however, it was not a simple case of unloading the machine and putting it to work.

Snapshot

Owners: Peter and Michael Sadler
Location: Wongan Hills and Bindoon, Western Australia
Farm size: 5422 hectares; 3962ha arable
Rainfall (long-term mean annual):
343 millimetres at Wongan Hills; 660mm
at Bindoon
Soil types: light loams (Wongan Hills); gravel to gravel loam (Bindoon)
Soil pH: 5 to 5.5 (calcium chloride)
Typical crop rotation: wheat/wheat/lupins (Wongan Hills); wheat/pasture (Bindoon)
Enterprises: cropping and 4500 sheep
Crops grown (2014): Calingiri and Mace wheat; PBA Gunyidi lupins

Peter employed agricultural engineer Charlie Mackintosh to build an interface between the HSD and his Case IH 9120 harvester (an interface is needed to match the HSD with different harvester makes).

The work involved adding an auger, fan and belt drive to the back edge of the sieves to enable chaff from the sieves to be fed into the HSD. Mr Mackintosh also had to fit a tow hitch to the rear of the harvester.

The extra work cost about $15,000, but the time it took allowed Peter and Michael to focus on harvesting their lupins and establishing narrow windrows until the machine was ready.

Looking back, Peter says the belt drive system is the weakest part of the interface because blockages in the auger could lead to burnt belts. In his view, a hydro-motor (oil) drive would be a better alternative because a relief valve would be triggered if a blockage occurred.

After fitting the interface, Peter and Michael put their HSD to work and used it over 2700 hectares in 2013. This meant only 400ha needed to be windrow burnt in 2014.

Weeds challenge

Ryegrass and wild radish are the Sadlers’ biggest weed threats. Peter says their farm near Bindoon, sown to wheat in 2013, was “quite bad with ryegrass” because dry conditions at sowing meant Sakura® herbicide was not activated, even though they had measured plenty of rain before sowing.

By contrast, the Sadlers’ property south of Wongan Hills was relatively free of ryegrass, except for patches in their lupins. This had usually been dealt with through crop-topping and windrow burning, but from 2014 they switched to using the HSD and crop-topping.

Harrington Seed Destructor specifications

Motor: Cummins QSB 6.7-litre six-cylinder
Maximum power: 153kW (205hp) at 1800 revolutions per minute
Drive: Triple stage hydraulic pump
Cage mill rotation speed: 1400 revolutions per minute
Cage mill diameter: 0.9 metres
Cage mill width: 0.25 metres
Cage mill composition: 2 x 3-row counter rotating cages

In a paddock sown to lupins in 2013, Peter says he could not see any immediate difference in the weed population where they windrow burnt and where they used the HSD in 2014, although the expectation is to drive down the ryegrass seed population over three years.

Peter says that operating the HSD went well in 2013 except for a small problem with an oil sensor: “If the sensors play up, they close down the machine to protect it. We didn’t know what the issue was until we asked Charlie Mackintosh from Wongan Hills and Kevin Jones from Dalwallinu to take a look at it and once they found the problem, we haven’t had a hiccup.”

Peter says areas he would like to see improved on the HSD include a more efficient straw-spreading system, the addition of a few more lights and audio alarms for the header driver to observe in the cabin, and improvements to the oil cooler.

He also wonders if the addition of a straw chopper might be valuable, enabling the one on the harvester to be turned off.

“The best part about this model HSD is the oil hydro-motor,” he says. “The previous model was belt driven and we believe they were a bit of a pain.”

He says the weakest part was the cooling of the 700-litre oil reservoir, which became very hot when the radiator became blocked with dust and straw. Michael now uses compressed air to remove the dust and straw from the radiator each day.

Peter and Michael did not push the HSD hard in 2013 because they wanted to ensure there were no major setbacks: “But we gradually increased our speed over time and were sitting at about 28 tonnes per hour to 32t/hour most of the time. You could push it up to 40t/hour, although you’d be safer around 35t/hour.”

At Bindoon, where some wheat yielded 4t/ha, Peter says the HSD handled the conditions well.

In terms of running costs, Michael estimates the HSD used between 18 and 20 litres of diesel per hour.

John Millhouse, general manager at de Bruin Engineering, says the areas of improvement Peter mentioned have been taken on board. Some have already been incorporated into the 2014 model while others are still being researched. 

More information:

Peter Sadler,
08 9672 1024,
petersadler@hotmail.com;

de Bruin Engineering,
08 8721 3888,
dbesales@debruingroup.com.au

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Herbicide resistance now a matter of can-do management

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SA trial assesses different weed strategies

GRDC Project Code CGS00001, UWA00146, USA00008

Region South, West