Curbing erosion an uphill battle
EROSION: A huge amount of farmland has simply slid into the sea. Donna Russell reports on grants to reverse the trend.
Sediment starts at the top so Northland landowners are being encouraged to consider retiring erosion-prone hill country. Northland Regional Council land management adviser John Ballinger said much attention has been on riparian planting to stop stream bank erosion and keep stock out of waterways.
“That’s all good stuff and farmers need to do that work as a priority to keep up with Government requirements.
“But we also need to look uphill to where the sediment is coming from,” he said.
Ballinger said an estimated 40 per cent of Northland farmland is prone to erosion.
“We are wanting to target marginal pasture that is difficult to farm and is prone to slipping.”
The regional council has announced hill-country farmers might be eligible for a grant that covers roughly 75 per cent of the associated fencing costs.
Its water and land working party chairman, Justin Blaikie, said the council had set aside about $600,000 to help fence erosion-prone land over the next two years.
Blaikie, who represents the council’s Hokianga-Kaikohe constituency, said that, depending on the size of the area, fencing costs could be considerable and a potential barrier to those considering retiring erosion-prone hill country.
Although a natural phenomenon, eroded sediment is Northland’s single biggest natural pollutant. Research shows the Bay of Islands alone has lost an average of 500,000 tonnes a year for the past century.
“It makes good environmental and economic sense to remove erosionprone hill country from being actively farmed to reduce potentially unnecessary erosion and either leave it to revegetate naturally or plant it out.”
The council requires retired land to be fenced with a three-wire electric fence as a minimum.
For those keen to actively plant retired areas, the regional council also has grants available.
“Grants include native retirement
It’s about protecting our soils from running off the hillsides into the harbours and protecting our water quality and kaimoana that suffer from the sedimentation.
— Glen Coulston, Mimiwhangata landowner
planting, or native and exotic production with species suited to continuous cover harvesting and council will help prepare a planting plan with landowners as part of this service.”
Blaikie said the size of the grant depends on a range of criteria including the size of the property, erosion severity and area of land to be retired.
‘About protecting our soils’
One of those who has already taken advantage of the scheme is Glen Coulston of Mimiwhangata, who this year received $10,000, subsequently retiring about 12 hectares.
Coulston had allowed the retired land to naturally revegetate due to strong manuka regrowth and was helping the process by carrying out weed control.
He plans to retire more steep sections around his 83ha property.
He encourages those looking to retire erosion-prone land to take the opportunity council and Ministry for Primary Industries are providing.
“It’s about protecting our soils from running off the hillsides into the harbours and protecting our water quality and kaimoana that suffer from the sedimentation.
“On this property we are looking towards 200-year selective native forestry, apiculture, carbon storage and harvesting of essential oils as options, while also retaining pastoralism and horticulture on the stable soil sites.”
Ballinger said the regional council aims to fund innovative replanting projects that can become inspirations for other farmers.
“Pine has a place as it will grow anywhere, but there are some interesting possibilities with native plants like manuka and totara, which grow really well in Northland and the stock will not graze it.
“Other trees that are creating interest include eucalypts and redwoods, which are among the species that can be coppiced so the roots remain as a living mass and the tree will grow back again,” he said.
Ballinger said sediment would eventually end up in the harbour and measures to stop erosion at the source would help water quality, “starting at the top of the cliff instead of being the ambulance at the bottom”.
Farmers interested in the grants or advice on retiring land can contact regional council land management staff.