Cover on the Coast

The Oats family use their composting mootels on the West Coast with the same dynamic approach they use throughout their farming business.

Seasons are rarely predictable and can throw some real curve balls when you least expect them, so having the flexibility to change course can make a real difference in their high-rainfall climate. Their goal is to lengthen the production curve each season to achieve consistent results and though it is still early days, the mootels are already making that more achievable.

This is Thomas and Hannah’s second season as 50:50 sharemilkers for Thomas’ parents, Tegal and Wendy, on the 169-hectare (effective) farm just south of Reefton.

They milk 370 crossbred cows at 2.2 cows per ha on a farm that has a mix of soils spilling over terraced country. Ninety-six ha is humped and hollowed land or flipped soils on the heavier ground, while a further 28ha sits on peat and 45ha is free-draining river silt.

It works out a good mix, with the peat surviving summer well and Thomas says it is beautiful soil but has an iron pan layer underneath which means it relies on evaporation in a rainfall that averages two metres a year. In a wet winter it can be tricky to manage to avoid pasture damage.

Hence the composting mootels.

Thomas says the wintering barns suit the farm and they have been a natural progression for farming on the West Coast, while acknowledging every farm is different. The couple were contract milkers for six years on the farm, before heading further down the Coast to Kowhitirangi for four years sharemilking and then returning last year.

“When we were contract milking here and walking between feed pads to crops, I thought it would be so nice to have them inside and feed in situ,” Thomas says.

The role of the mootels is to complement the farming system and Thomas says little has changed apart from feeding and calving the cows inside. They have not bought machinery to feed the cows inside the mootels and have spent little extra once the mootels were completed. It cost about $1 million to complete the two mootels which are Smart Shelters with woven plastic roofs. About $250,000 of that was spent on site preparation, while about $100,000 was poured into concrete.

The chosen site was on humped and hollowed land beside the dairy and beneath that lay glacial deposits of gravel. They removed the surface down to the gravel and then built it back up for the mootels. Once mootels were completed, about 3000 cubic metres of woodchip was added.

The mootels total 3240 square metres and are designed for 400 cows with 200 in each, which equates to about 8m2 per cow, though they are running them closer to 10m2. They chose plastic roofs on price, but also like the extra light inside and though they come with a 12-year warranty, Thomas says they are generally lasting up to 18-or-so years on other farms.

Inside, the woodchip is 900mm deep in the centre of the mootels and between the combined mootels equals 1000 tonnes of logs. Thomas says that is a small amount in the world of woodchip when questions are raised about future availability.

The two mootels were still being completed when Hannah and Thomas came back to the farm last year, so cows did not go in until June 28, 2022. Already, they are convinced the mootels are a good addition to the farm and complement the existing system.

That farm system is pretty simple and aimed at fully feeding the cows or “efficient cow centric” as Thomas says. In the past the farm had 5ha of winter crop that was generally swede and 5ha of turnips for summer. They will continue with summer crops, depending on the season. That is part of their dynamic farming approach; to have flexibility in their system. Running a lower stocking rate helps that flexibility.Part of their keeping-it-simple approach is retaining every paddock perpetually in grass.

“I don’t see the reason for resowing paddocks if we’re looking after them properly,” Thomas says. “There is grass on this farm that is 20 years old and they’ve got to a good equilibrium where the soil structure is there and everything works.” On top of pasture, the herd is generally fed 2kg of meal per cow per day throughout the season and sometimes 3kg at mating or depending on the weather, so ends

up averaging about 2.5kg. Meal is made up of 50% DDG, 25% palm kernel and 25% soya hull pellets. It is a feed mix and ratio that works on the farm, with no chance of acidosis, is palatable for the cows, while minerals can easily be added in when needed.

They also make about 400 tonnes drymatter (DM) of pit silage each year, about 240t DM from the milking platform and 160t DM off Tegal and Wendy’s support block. Last year they also purchased 130t DM of maize grown on contract on the Coast which was fed out through autumn and winter and they are doing that again this year. The mootels now give them the ability to feed it to the cows without wastage.

A concrete apron runs on the outside of the mootels to feed the cows and 400mm-high boards have been added on the outside of the feed strip to create a trough area to hold feed. That saves them the job of pushing feed back toward the cows when they flick it out on to the gravel beyond. With the benefit of hindsight, Thomas says another 600mm of concrete width would have been good to run the inside tractor wheel to make it a bit easier to pick up dropped feed. They also lowered the bar the cows reach under to feed as it was too high for the crossbred cows. If they were pushing for a feed when they first went into the mootels, the occasional cow would get under it and outside. Because of the mix of soils over the farm and high rainfall, they need to be flexible about their choice of paddocks to send the cows each day which means they do not follow a set plan for grazing. The beauty of the mootels is they now have that option in the mix and that is also based on flexibility rather than a set plan.

“In summer the cows went inside from mid-January through to early March from midday to about 3pm, depending on the day. From mid to late April they went in for their silage depending on the weather. If it was going to be wet at night they went in at night and if it was fine we fed them after milking and they went to the paddock.

“It’s about being dynamic and you need to be dynamic when you’re farming here. It’s a symptom of the farm and we farm with the sheds like that too. If we think they need to be inside, we put them in. If it’s wet weather, we don’t want them hanging around in the paddock. It’s having that flexibility and I think we’ll always tweak it.”

“Every season is going to be different,” Hannah says. “We don’t have a set plan.”

Production was up last season from previous average of 168,000kg milksolids (MS) to 186,000kg MS, despite a dry spell between December and March which led to an estimated loss of 5000kg MS. This season they achieved 505kg MS per cow, up from 470 to 480kg. They followed their usual milking regime which is twice-a-day milking through to January, when they switch to 3in2 and then down to once-a-day from about April 20.

Their season begins on August 16 to match the growth curve and the herd calves quickly without intervention. At between 11 and 14 days the herd hits its calving mid-point and Hannah says that is pretty consistent.

They mate for 11 weeks, but more cows calve earlier. It helps that Hannah is an artificial insemination technician and she says their early-calving rate revolves around watching cows throughout the day and then inseminating cycling cows in the afternoon. As Thomas says, missing a couple of cycling cows each day equates to about 11% of the herd over three weeks, so it’s worth monitoring them through the day and it is an advantage being able to AI the cows themselves.

Their later start to calving just makes sense to them and Thomas says a delay of 10 days to two weeks makes a massive difference to how the rest of the season plays out. The grass growth is beginning to take off and the cows calve, recover and get on with the season.

“The real figure is calves on the ground and consistent every year. Any intervention at mating I see as an ambulance at the bottom of the cliff.”

Hannah says one of their goals is to have their cows as fat as possible and she points out it is never the fatter heifers that are not in calf. The mootels are a good addition in the system to guarantee the ability to put weight on the cows through winter and they can do it without having to transition them on to crop to achieve that. This is the second season they have calved on the compost and it has gone well. No more checking paddocks on wet nights for cows calving. They were worried there might be more mastitis in the herd if they were calving on the compost, but it has not been an issue at all this season.

Last year they did have 12 cows with E. coli mastitis, possibly because the woodchip was not hot enough to kill nasty bacteria. Also, as the woodchip was new, the feed lanes were more compacted and preferable for the cows to lie on. That meant they tended to lie on the dirtiest woodchip. This year the woodchip has composted more throughout the mootels, so it is warmer and firmer over the entire area and the cows choose anywhere to lie down. After the E.coli mastitis, they have opted to use mid-acting dry-cow therapy and teat seal the entire herd without further problems. Plus, they flipped all the compost with the tractor bucket in winter to keep up aeration. Compost is the biggest learning curve for them. They till it every day when the cows go in the barn to aerate it down to 500mm and they plan to try a chisel plough to mix the compost more and see how that goes. Taking a scoop of compost out with the tractor bucket shows the compost is still reasonably fresh woodchip at the bottom. Steam rises from the overturned composting chip which is part of the critical heating process for good composting.

“We went into this with our eyes wide open and didn’t know how the compost was really going to work,” Thomas says. “If you got it wrong, we thought we would have to start again. But you can rectify just about anything in my opinion. But you do have to be diligent.”

On the environmental side, nitrogen loss has been reduced by 18% on the farm due to fewer urine patches on the paddocks. That is a lot less than two other farms in the composting mootel study because Hannah and Thomas’ barns are used less and they only began using them in late June. But it is significant. On a per hectare basis, the nitrogen loss was reduced from 60kgN/ha before the mootels were added, to 49kgN/ha.

Samples taken from the compost in May this year assessed it as future fertiliser as it will eventually be distributed on the farm. The total value of the compost was just over $32,000 or $92/ha that included nitrogen, phosphorus, potassium and sulphur. Thomas says that figure has probably doubled since the samples were taken due to more use.

Meanwhile, the family say the capital expenditure on the mootels will not necessarily add that figure to the value to their farm. In fact, it probably won’t. But Thomas says it might improve saleability immensely and is definitely making it easier to farm.

“It’s not all financial; it changes the outlook someone has of their farm business.”

“It would be hard to go back to farming without a barn on the Coast,” Hannah adds. “We weren’t doing this for the production – we had no production targets attached to it. We feel it is a natural progression – it’s about cow health and happiness, the environment, milking longer and less feed wastage.”