Corn turns dairy business on its ear

The addition of maize silage to the nutrition program is helping to power an ambitious expansion program for Gippsland dairy farmers, Alex and Olivia McArthur.

Together with their team of eight full-time staff, the McArthurs milk about 1000 Holstein, Jersey and crossbred cows across 440 ha of owned and leased blocks on the Macalister River outside Maffra.

The aggregation has nine centre pivots and a 250 ML irrigation licence. The McArthurs are about to plant and their third ‘home grown’ maize crop.

“The introduction of maize silage has turned this business on its ear,” he says.

“The improvement in our cows has been phenomenal.

“There’s only so much you can feed a cow.

“Maize is allowing us to keep the grain at 7 kg/day but increase the starch and fibre content.

“Our production has jumped to about 600 kg milk solids per cow.

“Better nutrition is not just about production, it’s about health and fertility.

“Cows are putting on weight during the lactation and some are even getting fat.”

Alex says the maize is extremely cost effective.

“It’s much cheaper to grow than buying grain or hay,” he says.

“Regardless of its cost, the real beauty of maize silage is that I know what it is and where it is.

“As a dairy farmer, I am always going to be a price-taker, but at least with silage, I have some control of my input costs.

“Maize is a bit daunting to grow but it’s better than waiting to find out what happens.

“You have to be in control of your destiny.

“A couple of years ago, we got caught out and had to buy hay.

“Until then, I hadn’t completely realised that 700 cows don’t just need hay, they need hayshed’s of it.
“At one stage, we were paying up to $400/t for really poor-quality hay.”

After experimenting with strip-grazing millet and sorghum with mixed results, Alex grew his first maize crop in 2021.

“We had just purchased another block with a 24 ha centre pivot, which meant we could grow a dedicated forage crop,” he says.

“We did everything right but we had a terrible year with a flood and then two inches of rain.

“There were carp swimming in the paddock!

“You can always recover a moisture-stressed crop but a flooded crop never recovers.

“We lost two hectares outright but we managed to get 20 t/ha from the rest.”

Undeterred, he planted a second 41 ha crop last year across five elevated paddocks.

“We managed our inputs a little more conservatively,” he says.

“We planned for a yield of 18 t/ha and harvested 20 t/ha.

“This year, we are going to plant 60 ha of maize, which should produce about 1200 tonnes of wet silage.”

Alex relies heavily on Maffra-based Nutrien Senior Agronomist, Jim Colquhoun, and Yarram-based silage contractors, Wayne and Hayden Bowden.

“We do everything ourselves, except the maize, and for that, we rely on Bowdens to plant and harvest the corn,” he says.

The stack is built on a shaped ‘hump and hollow’ gravel base above the flood line.

Harvested forage was treated with MAGNIVA Platinum forage inoculant during processing. It combines a patented strain-specific bacterium, L.hilgardii CNCM I-4785, with the industry standard, L.buchneri NCIMB 40788. It contains a number of special enzymes to assist with rapid fermentation.

The 20 x 100 m stack was then covered with SiloStop oxygen barrier film to limit the growth of spoilage-causing yeasts and moulds. The 45 micron film is protected by an outer layer of SilageKeeper UV covers, designed to protect against the impact of UV light and damage caused by animals and environment.

The two layers are sealed with SealKeeper gravel bags, which are re-useable and environmentally-friendly alternative to car tyres. In addition, cement-stabilised sand was used to seal the edges. Alex says moving to bulk silage was reasonably cost-effective.

“People think you need to spend a lot of money but we didn’t,” he says.

“We picked up a second hand wagon for $10,000, we already had another tractor to tow it and we feed out into the paddock, the same as everyone else.

“It’s not ideal but it’s working for us at the moment.

“The most expensive thing we’ve bought so far is a used wheeled loader with a 4.5 cubic metre bucket for $50,000.

“We are saving at least an hour a day compared to using a tractor and a bucket.

“Ideally, we should be using a shear grab to prevent oxygen from entering the face, but we’re removing a lot of silage every day, so we are keeping ahead of potential spoilage.

“We’ve probably only thrown out three cubic metres, max.”

Alex says maize silage is underpinning his growth plans.

“I wish we’d done this years ago but we had a dozen other projects that had to be completed first,” he says.

“Olivia and I did a training course with our bank a couple of years ago and it emphasised the importance of doing the little things that count.

“Maize is the most important ‘one percent’ we’ve done.

“Being able to produce our own source of high quality fodder is going to enable us to grow.

“Currently we are running the cows as two herds and milking them in separate dairies.

“The ultimate plan is to expand to 1200 or 1400 cows and construct a new dairy and feed pad.

“In the meantime, we’re looking at other crops, such as fodder beet.”

Alex still produces approximately 500 tonnes of tube-wrapped silage for feeding during the shoulder season.

“If you can’t do pit silage, then tube-wrap silage is the next best thing,” he says.

“We used to cut about 2000 4’ bales but the amount of spoilage was horrific.

“Every time you grab a bale, you squeeze air out of it, which simply sucks back in when you put it down.

“You can easily waste a third due to spoilage and we had lots that were cooked half-way through – that’s three quarters of the bale gone.

“Plus they produce enormous amounts of waste plastic.

“Now we are wrapping two 5’ bales, which is the equivalent of three 4’ bales, with significantly less spoilage and half the plastic.”

Alex and Olivia purchased their first 100 ha block outside Maffra in 2006.

“Our original intention was to get into lambs and beef but we decided to go dairying instead because it made more sense,” Alex says.

“There was already a dairy on the farm and that’s the main industry around here.

“We bought 180 cows and got started.

“I grew up on a beef and sheep farm and had never milked a cow in my life, so it was a very steep learning curve.

“We had a drought and then a flood in our first year.

“When we started, we were 100% focussed on getting the pivot going and growing more grass.

“Now we’re focussed on growing better feed and nutrition.

“You can have the best grass and the best genetics, but if you don’t have the feed in front of them throughout the lactation you’re never going to see a return.

“It’s all come together in the past two or three years.”