Aiming for zero

By Hugh Stringleman

Two wetlands drain a Northland farm that has set out to have no impact at all on nearby freshwater resources

Wetland development, riparian planting and reduced sediment losses to waterways were highlighted at the field day for the 2023 Ballance Farm Environment Awards supreme winners in Northland.

Andrew and Vicky Booth of Jade Dairies at Titoki near Whangārei, are 50:50 sharemilkers on the 220ha family farm (174ha effective) for Andrew’s parents, Richard and Sharon.

They also employ Bill Hamilton, who won the 2023 Dairy Trainee of the Year national award.

Ninety percent of the farm is drained through two wetlands, one pre-existing and never modified and the other newly retired, fenced and planted under Andrew’s management.

The Booths aim to have zero impact on surrounding freshwater, so the farm is run with careful use of nutrients and a good understanding of high-risk areas.

The wetlands trap nutrient run-off before water leaves the farm.

Two-thirds of the farm is top flat plateau with volcanic and peaty soils and the remainder hillsides going down to river flats, with silty loam and clay soils, along the Mangakāhia River.

Andrew says the river, flats and wetlands have flooded 16 times in this extraordinary season of way above average rainfall.

Some smaller plants have been lost or lodged and a covering of silt remains over the hardy species like coprosma, mānuka and flax.

Andrew and Vicky are in their 13th season on the farm, where Andrew grew up as did his father before him.

They are very aware of the potential impacts of climate change on dairy farming in Northland.

“You don’t have to own the land to look after it – we would do the same wherever we are farming,” Vicky says.

Andrew is a DairyNZ climate change ambassador, and a member of the Dairy Environmental Leaders Group and the Northland Dairy Development Trust.

He is very motivated to be a positive voice for farming, following in Richard’s governance footprints, because the Booths are proud of what the industry does.

“There is so much good stuff happening in farming, not just in dairying, and these awards showcase the good.”

He told a large crowd at the Northland Ballance Farm Environment Awards (BFEA) field day recently that establishing a big wetland may look like a Herculean task but it can be accomplished by beginning with good planning, short bursts of labour and perseverance.

All avenues of outside help have been followed, including planting days by children and parents from local schools.

Andrew says the purchase of plants and the planting were not overly expensive, but some regular maintenance is required and should not be neglected.

The wetland plan was drawn up five years ago and approved and co-funded by the Northland Regional Council (NRC), which had many land management officers and elected representatives present at the field day.

NRC is evidently proud of what has been achieved on the Booth farm, and its example to other landowners within the Kaipara Moana Remediation programme, because the Mangakāhia joins the Wairoa River and the Kaipara Harbour.

The presence of the Australasian bittern (matuku hūrepo) is a welcome sign of success.

The farm follows Fonterra’s figures on greenhouse gas emissions, generated from the regional benchmarks, cow numbers and the fertiliser spreading histories.

They show that Jade Dairies is below average on biological emission figures – 9.5kg CO2e/ kg milksolids, 7139kg CO2e/ha in methane, 1566kg in nitrous oxide and 8705kg/ha in total.

“Now we have reliable numbers there are a few levers to pull, like putting on less nitrogen, increasing feed efficiencies and breeding more efficient cows,” Andrew says.

Climate change is evident through lack of frosts and more extremes in weather and the responses include reducing stock numbers, conserving more farm-grown fodder and using newer pasture cultivars to keep kikuyu infiltration down.

Jade Dairies is full autumn calving with 390 to 400 cows, having changed over from spring calving and reduced cow numbers by 25 to 35.

Milking through winter suits the farm soil types and pasture growth rates during the milder winter months. Having dry cows during the summer also takes the pressure off pastures.

Fertiliser applications are planned for each of five main soil types and nitrogen applications are light through autumn and winter.

“We use about 100 units of N per hectare, which is not high, and we apply where we will get the best results,” Andrew says. n