"My decision comes after deep consideration of what is best for the co-operative going forward," Mr Roadley said.
"When I agreed to accept the challenge of leading our co-operative. . . I made it clear that I saw the role as comparatively short term, to steer the business through the high risk and difficult period of establishment," he said.
"I set myself three goals -- to ensure our shareholders agreed to the merger, to see the co-operative through the risky transitional first year, to achieve consensus among the board and management on Fonterra's future business strategy."
Mr Roadley said the various problems that have plagued Fonterra since its formation, such as Powdergate and milk collection problems had nothing to with his leaving.
Mr van der Heyden was the only nomination for the chairmanship which raised questions as to why deputy chair Greg Gent did not step up.
He said he had two priorities as chairman: to maximise the payouts to farmers in spite of the difficult international market and to focus on achieving the $300m a year merger benefits.
Mr van der Heyden said John Roadley was the only person who could of got the two formation companies "over the wire " to form Fonterra.
Mr Roadley was recently awarded Melbourne's Monash University Sir John Monash gold medal for his part in setting up the company.
He was the chairman of the Dairy Board and the chairman-designate of the industry's mega-cooperative in the lead-up to the official formation of Fonterra last October.
With the creation of the company from the Dairy Board, New Zealand Dairy Group, and Kiwi Cooperative Dairies, Mr Roadley took over leadership of 13,000 dairy farmers and nearly 20,000 staff in 120 countries.
Mr Roadley began publicly agitating for the mega-cooperative in 1995, while chairman of Alpine Dairy Products in Canterbury.
The previous year the nation's biggest dairy company, New Zealand Dairy Group, pushed to corporatise the Dairy Board, but Mr Roadley said in April 1995 he had serious doubts about how smaller companies like his would fare under a corporate industry structure dominated by NZDG.
In July 1995, Mr Roadley unveiled a study by four smaller companies, Alpine, Northland, Tui and Bay Milk, which identified potential revenue boost of $280 million -- equivalent to an average of $20,000 annually for each dairy farmer.
He pushed for the plan, which required the total integration of manufacturing and marketing in the industry's then 15 co-operative dairy companies, to be taken up by the wider dairy industry.
Mr Roadley later oversaw the merger of his own company with Southland Dairy Co-operative to form South Island Dairy Co (SidCo) to give it greater clout in future mergers.
When SidCo was later taken over by NZDG, rejecting a bid by Kiwi, Mr Roadley became a director and later deputy chairman of NZDG, and after the cornerstone merger of NZDG and Kiwi, became head of both the Dairy Board and the "Global Dairy Company" that became Fonterra.
Mr Roadley grew up on a dairy farm near Maungaturoto, north of Auckland, and began farming there.
In 1980, he and his wife Lois moved south, buying a 149 hectare property near Ashburton. Growth and acquisitions over the last 20 years have seen Roadley Farms grow to 1000ha, split into three farms and 2200 cows.
Mr and Mrs Roadley have two sons, a doctor and a dairy farmer.
- NZPA and HERALD STAFF
nzherald.co.nz/dairy
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