Squeezing the fluids from dairy effluent and mixing the resulting solids with sawdust offers a comfortable surface for cows to stand on for a farm in a high-rainfall area. Anne Hardie reports.

The squeezed solids from Brent and Kathy Page’s dairy effluent on their Golden Bay farm is going to form the base for the wintering barn next year, mixed with sawdust for the cows to stand on during heavy rain.

The Yardmaster Separator Press.

Until recently, the dairy effluent was stored very temporarily in a pond before being irrigated over the pakihi terraces on the farm that sits just across the river from the tiny Takaka township. Though compliant, Brent says things had to change and the result is the squeezed solids that will be recycled through the wintering barn.

The family runs a diverse and expanding business that centres on the farm Brent’s great, great grandfather began carving from the bush in 1852. In those early days, three acres of contract hops was grown for the country’s fledgling beer industry and over the decades the bush gave way to terraced pasture on poor, pakihi soils that have been developed to productive dairy country with a rainfall between three metres and 3.5m each year.

‘We cart all the calves over the hill and guys haven’t hesitated to buy them this year because they’re on our truck.’

Today, that first farm (number one farm) covers 310 hectares that milks 800 cows, while the business has expanded to the neighbouring farm (number two farm) where 200ha milks 550 cows through its own

50-bail rotary. Their best production has been 320,000kg milksolids (MS) on the number one farm and 230,000kg MS on the number two farm with inputs of rolled barley, maize silage made on farm and a couple of tanks of molasses at calving.

On the other side of the Takaka Hill ­ a daunting drive for tourists and notorious for slips, as ex-cyclone Gita proved earlier this year ­ they run their drystock and dairy support block, covering 400 freehold hectares and another 250 leased hectares.

It’s a valuable asset that enables them to be self-contained, raise dairy beef from the dairy herds and provide much of their supplement needs. This July, the in-calf heifers and cows returned to Golden Bay with a new system in place to handle their effluent.

The number one farm has two herds milked in a 54-bail rotary and effluent now passes through a stone trap to a swirl pool with a submersible pump working a stirrer to keep the solution in suspension, then through a Yardmaster Separator Press that squeezes the liquid from the solids.

Liquid runs into the 1.8 million litre above-ground Tasman tank with sides 2.7m high. A cover is used to keep the rain out, as the high rainfall would quickly fill the tank, and any rainfall collected on top of the cover is pumped off to a drain.

Meanwhile, that green water collected in the tank is used to wash down the yard after every milking and instead of using 30,000 litres of fresh water per milking, drawn from a bore, totally recycled water is sprayed from the backing gates.

Gone are the days when someone had to hose the yard down after milking the only hose down now is inside the dairy where fresh water still does the job.

Under the separator press, the squeezed solids are almost dry and resemble the grass that originally produced it, with only fine sediment going into the tank that can easily be irrigated through the K-Line irrigation on to 80ha of paddocks, or washing down the yard. The plan is to expand the irrigation area to spread effluent on to areas that dry out more through summer.

Brent is impressed with the quality of the separator press and the dry product it has produced. The idea of using it in the wintering barn followed a visit to a Southland farm where the solids from the press had been combined with sawdust and produced a quality potting mix at the end of winter.

A usable product.

So through the season, Brent intends carting the pressed solids to the wintering barn, ­a Redpath shelter ­to keep it dry until the cows move in next winter. The plastic-covered dairy shelter has a feed area through the middle and sits on the leased block which was a smaller dairy farm in the past. During heavy rain events at night, Brent says they put 200 cows in each side of the shelter which was quite tight, but it was an alternative to the laneways and gravel areas and the cows benefited.

Though Golden Bay has a high rainfall, it’s a temperate climate and Brent had never considered any form of wintering barn, but seeing the cows under shelter this past winter has won him over.

“The cows loved it there over winter because they generate their own heat. And there was the peace of mind knowing the cows were under cover. So we’re toying with putting one on the number two farm now because of the pakihi soils.”

The new effluent system which all-up cost about $300,000, isn’t the only addition around the dairy. The rotary was built in 2002 but has been ideal to modify over the years as technology became available. Today it has teat wands, automatic cup removers, Protrack and meal feeding­ using the silos, roller mill and molasses tank outside­ plus the latest addition to snap chill the milk going into the vat. The $40,000 Tru-Test ice bank can cool milk to 5C at peak milk flow which is 20,000l a day.

Brent’s son Nathan is the sixth generation on the farm and along with partner Emma has taken on the role of contract milker on the number one farm this year, plus operations manager for both farms. Brent helps out where he is needed, including the Motueka farm which last year earned the business another dollar for every $1/kg MS from the dairy farms. In the past, when the milk payout plummeted to $3.90/kg MS, stock sales provided vital cashflow for the business, he says.

A decade ago, the dairy herd was predominantly crossbred cows, but that has moved toward Friesian because they decided they could feed the larger Friesian cows and they provided another income stream through the sale of Friesian bull calves. Each year, between 100 and 130 Friesian bull calves from artificial breeding (AB) are reared on contract and sold at 100kg to North Island buyers to finish.

Hereford bulls are run with the later-cycling cows and Brent says those calves are always in demand. The heifers are bought by a local farmer at four days old and the Motueka farm rears about 120 Hereford-cross bull calves which are later sold between 16 and 18 months old as forward stores.

“I don’t take them through a second winter because it’s more important we do our dairy stock well. All our R1 and R2 dairy stock run over there and the R2 come back here on the drop and sometimes after they’ve dropped, though that’s not planned!”

They’ve got a lot of stock to cart over the Takaka Hill from the two farms at the end of the season and then back again for calving, plus calves heading to the Motueka farm, so these days they have two truck and trailer units to do the job themselves. The threat of Mycoplasma bovis being spread around the country has made those two trucks valuable assets for themselves and the farmers who buy their stock.

“We cart all the calves over the hill and guys haven’t hesitated to buy them this year because they’re on our truck.”

A stirrer keeps the effluent solution in suspension before it heads to the press.

They don’t have a completely closed herd as they buy in Hereford bulls from a farmer they have dealt with for years. This year, due to M bovis, Brent will head down the West Coast in one of their own trucks for the long trip to pick up yearling bulls from the Fox Glacier breeder. The bulls are used as two-year-olds as well as yearlings which means they get two years use out of them and always have 30 Hereford bulls at any one time.

As well as yearling Hereford bulls, Brent buys 60 weaned Jersey bull calves each year ­ but not for their own use.

“We buy them from purebred Jersey farms at 100kg and the last couple of years we paid $420. We’ve been supplying the same local farmers for 10 to 12 years and they go to them as two-year-olds in October-November and we get about $1700.

“Bulls are always a hassle on a dairy farm and some of the farmers don’t even want them until they’ve finished AB and then they works them after using them.”

The trucks are also put to good use bringing balage and hay from the Motueka farm, with about 400 six-string bales of balage made each year and carted to the dairy farms when its needed.

“Some days I can do two trips a day over the hill a day with hay and it’s about an hour and three quarters one way in a truck. It’s a matter of getting windows in the weather to make the hay and we fill all the sheds here on the dairy farms and over in Motueka for feeding out in winter and early spring.”

Maize silage has also been made for the dairy herds and Brent says it’s useful for putting weight on the cows in winter, but wet ground has meant they also waste a lot of it. So this year they are trialling palm kernel at 2kg/cow which he says may also prove a better option than barley which had climbed from $350/tonne last year to $430/t. Dairy farmers weren’t using barley when the payout was down, so the barley growers didn’t produce as much and now the prospect of a $7/kg MS payout is driving price up, with barley being imported from Australia, he says.

Prices also climbed for palm kernel, which he bought at the end of July for $267/t and two weeks later would have cost nearly $100 a tonne more.

Cartage adds a hefty cost to any bought-in supplements, with anything trucked from Canterbury adding another $80 to $100 a tonne to the actual supplement. Their barley comes from Blenheim which they can cart to Golden Bay for $40 to $50/t.

An option they are considering for next year is their own maize grain which they can put in the silo and through the roller mill to feed in the shed. That way they will have a high-quality feed with no wastage.

Even though it’s a high-rainfall area, dryland farming is unpredictable and inputs add consistency. Brent says they have grown both turnips and chicory in the past for summer feed, but both take paddocks out of the round for too long and they’re now concentrating on their ongoing pasture renovation. In a drier season they will drop cow numbers and go to three milkings in two days, but have never had to dry the cows off early.

Keeping good levels of fertility in the higher rainfall, especially on the areas of pakihi soils, requires regular dressings of fertiliser which they apply themselves.

“It’s been developed out of poor pakihi soil and you want to be able to get fertiliser on before a rain. If you were relying on contractors, everyone wants them at the same time and that can cost you production. So we have our own fertiliser bins and own sowers on all three farms.”

Going forward, the family is looking at buying a neighbouring property that has been a dairy farm in the past, which would add more land to their milking platform as well as support area beside it.

Farm facts

Owners: Brent and Kathy Page

Location: Takaka, Golden Bay

Dairy farms: 310ha milking 800 cows, 200ha milking 550 cows

Drystock farm: 400ha freehold plus 250ha leased

Best total milk production: 550,000kg MS

Effluent infrastructure: Tasman tank, Yardmaster Solids Separator, green water