Dairy development helping environment

20:47, May 28 2013
Merv McCabe
PROOF IN CROP: Little Ben dairy farm director Merv McCabe on his farm near Omarama. In the background is a winter feed crop of fodderbeet.

A controversial dairying development near Omarama is leading the way with its environmental practices.

It is still early days but the structure, fertility, health and depth of Little Ben dairy farm's soil has significantly improved over the past three years.

Farmers saw the progress the farm had made at a field day last week.

The 470ha farm operates as a partnership between Richard Gloag and Merv McCabe.

McCabe said the environmental improvements were a consequence of their farming policy rather than an intention.

"We haven't gone out of our way to do this for the environment point of view, it just so happens that this policy fits with the environment and is better for the environment."


There was also satisfaction at the farm's environmental progress after a two-year legal battle to get it established.

In 2010, the directors successfully appealed Environment Canterbury's decision to grant Little Ben a consent for 750 cows for 10 years.

The directors appealed the decision on the grounds that it was too "restrictive".

The appeal granted Little Ben Dairy effluent and land-use consents to farm more than 1400 cows for 25 years.

The court's decision was criticised by the Green Party and the Aoraki Conservation Board.

"The consent cost us $500,000 and we went round and round in circles.

"At the end of the day they granted us our consent and we virtually didn't have to change any of the structure that we had went to them in the first place."

The farm was a subdivision of Buscot Station and prior to the conversion, it was a barren, dust filled landscape situated beside the Ahuriri River and protected as Department of Conservation land.

Environmental considerations weighed heavily on the minds of the farm owners when making farm polices.

"We are very aware of our surrounding environment so we do everything possible to protect the river," McCabe said.

He is a strong believer in the benefits of ploughing and cultivation, saying it is the best way to add to the topsoil and improve fertility.

On one block alone McCabe estimated he gained about four inches of topsoil.

"Where we once had dust and sand, we now have that much black [soil]."

Environment Canterbury land management officer Ian Lyttle said increasing the soil mass was positive for the environment.

"It's contributing organic matter to the soil so there would be nutrients hanging onto the organic matter."

It would also build soil structure and help extend the pasture's root structure.

"It is a good thing to extend your root zone." Lyttle said the owners should be commended.

"Merv and Richard are looking after their soil pH and managing their nutrient application and effluent to minimise nutrient loss." 

The 5mm of irrigation water applied to pastures did not penetrate below the soil's root zone.  This meant there was less chance of losing nitrogen out of the soil. 

Little Ben's pastures are one to three-years-old ryegrass and clover, along with 100ha of fescue and lucerne planted the last year. 

McCabe favoured the deeper rooting system and grass grub resilience of fescue and lucerne compared to ryegrass. 

He does not use urea, instead favouring a Hatuma-produced dicalcic phosphate aglime blend of 700kg/ha.  Sulphate of ammonia is added to each application at a rate of 50kg/ha. 

He also applies biomax liquid fertiliser through the farm's irrigators at 6.2ka/ha on nitrogen per application. 

He uses dicalcic phosphate because of its non-soluble nature, which helps mitigate N leaching. 

His none-use of urea meant the farm was probably carbon positive because urea burned off carbon in soils. 

There was also evidence in the soil of worm castings, indicating the presence of a growing worm population and improved soil fertility. 

McCabe also uses pasture stimulant Pro-gibb mixed in with Biomax and applied through a boom sprayer during the shoulders of the dairy season. 

The farm has a 10 per cent improved production over the past two seasons, increasing from 546,000-598,000kg milk solids.  

The Timaru Herald