More lambs, less weeds in systems
Whatstarted as a drought mitigation measure for Horsham mixed-enterprise farmers Sam and Emily Eagle in 2014 has proven to be a valuable long-term livestock production and weed control tool.
Livestock containment areas allow the Eagles to rest their pastures and fodder crops, efficiently use a variety of feeds and restrict the spread of weed seeds. On top of this they have also seen benefits in growth rates and lambing percentages.
Sam said their six or seven hectares available for containment was not expensive to build and had made it much easier to manage their livestock and cropping enterprises.
“I’d definitely recommend building containment areas for sheep,” he said.
“It is such a simple concept that has so many benefits. They really help to manage ground cover on your pastures and cropping paddocks, and in dry times they make feeding out much less stressful.
“In the last drought we had up to 6500 sheep in containment, including lambs, and I could feed them all in less than three hours, and didn’t have to feed every day.”
Sam and Emily use the containment areas for several purposes throughout the year.
Although they generally keep their pasture and cropping paddocks separate, the sheep play an important role in weed management across the whole farm.
“The containment areas allow us to bring in feed from outside if necessary and feed out screenings from our own grain, being confident that any weed seeds that come with that feed won’t be spread around the farm,” Sam said.
“It is easy to manage any weeds that germinate in such a defined and small area of the farm.
“When we buy in sheep we shear them as soon as they arrive to remove any risk of them introducing weeds.
“We use the containment areas to avoid overgrazing pastures, so the sheep eat the weeds like barley grass as well as the more palatable species.
“They also provide an effective double-knock effect for weeds that have herbicide resistance.”
The Eagles cut weedy paddocks for hay or silage and feed it out in the containment areas where they can control any weeds that germinate.
Sam said above-ground pit silage had been very cost effective at about $10 a cubic meter, to cut the silage and store it under a tarp before feeding out in the containment paddocks.
“Silage is a very good weed control tactic,” he said.
“You cut it early, so you are stopping weed seed set, and after three days of
good weather you can spray out the paddock for a spray fallow.”
The Eagles prefer to either graze a crop fully or grow it for grain, having found the ‘grain and graze’ tactic for dual purpose crops had an unacceptable yield penalty and opened up the canopy to allow weeds to grow through and compete in the grain phase.
Sam said Moby barley plus clover was the best cover crop to graze and then spray out.
“Oats and pasture are both cut either for hay or silage to conserve fodder and remove weed seeds,” he said.
“In the cropping paddocks sheep will eat most of the weeds that have developed herbicide resistance, like wild radish, annual ryegrass, fleabane and whip thistle. They also generate
cash flow from cover crops and from grain crops that don’t go through to harvest due to drought, flood, weeds or frost.
“Over summer the sheep reduce our herbicide costs and reduce the stubble load, which makes sowing easier.
“Once the feed supply runs out, we put the sheep into containment until they start to lamb. This allows the pastures and crops to get ahead and gives us good feed to put the ewes into for lambing. The sheep can make interrow sowing more difficult in our CTF system so we have to be careful to cut the stubble 300mm or less above ground level so the stalks don’t lodge across the inter-row as the sheep graze the stubbles.”
Having used narrow windrow burning as their harvest weed seed control tactic for six years, Sam and Emily used a contract harvester with an impact mill for their harvester for the 2018 season.
Sam said they were pleased with the job the mill did and were looking to purchase one of their own once the technology matured a little more.
“We use crop-topping in pulses and windrowing in canola to stop weed seed set and also spray herbicide under the cutter bar in canola,” he said.
“We test weeds for herbicide resistance so we know what still works and plan out a diverse herbicide program with multiple chemical groups used in a broad crop rotation.”
Other than the grazing and weed management benefits, Sam and Emily have also found numerous productivity benefits for their 2500-strong merino flock.
Sam said using the containment yards for joining had seen increased conception rates.
“After preg-testing our ewes we make separate mobs for the twins and singles so we can better manage the ewe’s nutrition while in containment,” he said.
“Once the lambs are weaned and are brought into containment their growth and feed utilisation rates are higher than when paddock grazed, meaning the returns on feed inputs are higher and we are able to either turn off hoggets earlier or at a higher weight.”