Ashley and Lisa Mezenberg, from Denison, operate two farms, milking 600 cows; a self-replacing, predominantly Friesian-cross herd, with infusions of Normande, Aussie Red and Brown Swiss. The herd produces 3.7 million litres annually.
The home farm has a 26-bay swing-over herringbone dairy, to milk 400 cows. The second farm uses a 15-double-up herringbone system to milk 200 cows. Both herds are twice-a-day milkers.
The twice-annual AI program covers four weeks, followed by mop-up bulls. Both herds are split-calving to take advantage of spring and autumn growth. The Mezenbergs raise heifers for their self-replacing herd and the export market.
In the middle of the Macalister Irrigation District, the farms cover about 364 irrigated hectares, with 170 ha used for grazing.
The remaining farm land is used to grow out young stock and produce fodder as silage and hay. About 500 rolls of grass hay and 600 to 700 tonne dry matter of chopped grass and maize silage is harvested each season and buried in a pit.
“Grazing is 2.5 leaf stage year-round, which also enables silage and round bales of hay to be harvested each season,” Mr Mezenberg said.
“We normally do a couple of chops.
“If a paddock is not performing, we oversow with permanent rye-grass pasture.
“We also sow 18 ha of maize for winter grazing, to offset higher hay prices. Last year we sowed an additional 8 ha of maize.”
Irrigation is assisted by two re-use dams, one on each farm. On the home farm, about 120 ha is irrigated with flood; a 7 Ml re-use dam enables irrigation water to be captured and recycled through a flood system.
On the second farm, the excess flow from another 120 ha of flood irrigation is captured through drains and siphons and diverted into a 10 Ml capacity re-use dam, that enables the captured irrigation water to be recycled. Two bores also feed through a centre pivot that irrigates 40 ha and fixed sprinklers for 1ha.
The re-use dam reduces environmental damage in the MID system by minimising nutrient outflow — all fertiliser and nutrients stay on the farm.
While Mr Mezenberg’s focus is overall management and growing pasture and fodder, Mrs Mezenberg is part of the milking team.
They also employ a manager on the home farm, with a full-time employee and two part-time workers; main responsibilities are milking the cows and herd health. A couple is employed to manage the second farm and milk the cows.
Four years ago, Mr Mezenberg began a system of building compost heaps.
He contracted someone to manage multiple heaps, but decided it would be more efficient to have a large compost heap and take over responsibility for it himself. This has had a significant impact on reducing fertiliser costs and improving production.
“We’ve been composting for about four years. We had a guy come in turning compost, there were lots of small heaps. So I decided to make my own big one,” Mr Mezenberg said.
Along the way he has designed and built a compost turner that hooks up to the tractor and is driven by the PTO of a 200 hp tractor. It cost about $30 000 to $40 000 to build in materials and about six months of labour time, between farming work.
A 2000-litre capacity tub on top of the compost turner enables water and a liquid containing composting bugs to be sprayed onto the heap as it is turned.
“Any waste from the dairy farm, mouldy silage, feed pad effluent and mud, settling pond effluent, calf bedding, chook manure and sawdust when I can get it locally, a fallen tree and branches, it all goes into the compost heap,” Mr Mezenberg said.
“You have to keep turning the compost, keep it moist and between 40 to 60°C, to keep working but not create unhealthy pathogens.
“You need to check it every couple of days, turn it a couple of times a week.”
Sun and wind do not seem to have an effect on the temperature and quality of the heap, which measures 6 m wide by 2 m high and is close to the dairy on the home farm.
“It gets up to 100 m length in the area and is 10 to 12 weeks to maturity,” Mr Mezenberg said.
“The more you turn it, can mean you can use it quicker.”
It is a matter of managing the work needed doing on the compost heap with other farm jobs.
Mr Mezenberg spreads the compost with a solids spreader.
“You can spread it behind the cows if you like, over the pasture after the grazing rotation,” he said.
“We also put it onto paddocks that need a bit of attention.”
He has noted improvement in the soil over the past four years.
“The biology in the soil starts working and gets the water holding capacity up,” Mr Mezenberg said.
“Since we started using it, we’ve noticed our bulk feed is gradual-grown but consistent across the year. So we have more grass to graze year-round.
“You seem to be able to water less because there is less leaching and runoff, and more water-holding capacity in the soil.”
Previously, the annual fertiliser bill was $80 000. That is now reduced to half. The compost fertiliser can also be spread where and when it is needed, rather than waiting for a contractor to apply it.
“As a dairy farmer, we’re pretty time constrained, so making it onsite and having it available when you want to apply it, helps,” Mr Mezenberg said.
“It’s helping everything, the herd health, the soil health, we’re spraying less herbicides for red legged earth mite and other bugs. The soil is a lot healthier, which has got to be good.”
He was introduced to the process at information days in the Warragul area and has learned through trial and error and reading.
Creating, managing and using the compost heap, the couple have been able to meet their own ethical considerations about waste.
“I just want to grow more grass and reduce waste,” Mr Mezenberg said.