Land use in organic farms 'too high'

Organic farmers will need to shrink their land use if they are to conquer the mass market, says a Swiss expert.

The director of Europe's largest centre for organic farming research, Dr Urs Niggli, said that life-cycle assessments had shown organic agriculture had the edge over conventional farming when it came to making the same amount of food for less energy, water and greenhouse gases.

The drawback was that organic farming used more land - something researchers at the Research Institute of Organic Agriculture in Switzerland where he works were looking at.

Dr Niggli said the challenge was to figure out how to get more organic food from each hectare of land without losing the environmental advantages.

"The question of how to intensify agricultural systems without losing their environmental and ecological advantages is a crucial one."

Dr Niggli, who was in New Zealand to speak to farmers at the Organics Aotearoa New Zealand at the University of Waikato last month, said organic methods could benefit New Zealand because a large proportion of the country's greenhouse gas emissions came from farming.

About half New Zealand's total emissions under international limits are from agriculture.

Dr Niggli said studies dating back to the 1970s suggested there was potential to cut emissions using reduced tilling and other organic farming methods.

Trials in the United States, Switzerland and Germany had compared organic methods with state-of-the-art conventional farming methods and found that, over two or three decades, organic farming could store up to 590kg more carbon in the soil a year for every hectare of land, he said.

The organic tests tried techniques such as using composted manure as fertiliser, and rotating crops with a large proportion of legumes to trap nitrogen - a major source of greenhouse gases in New Zealand.

"By recycling manure, you permanently bring organic matter into the soil again," said Dr Niggli.

The 130-strong Swiss research centre is working on cures for other common ailments facing farmers.

Dr Niggli said scientists and vets were also looking for ways to treat mastitis - one of the major reasons for lower productivity in organic dairy farms, which are not supposed to treat animals with antibiotics.

A study of 120 farmers found half could cut chemical treatment of cows to almost nothing without losing productivity or milk quality, by keeping cows healthy with better feed, better housing, better milking techniques and more thorough veterinary advice.