A funeral was held at a Toowoomba nut processing plant on Wednesday for the eccentric American who convinced Australians they could grow pecans where only wheat and cotton had previously been sown.

Deane Stahmann, from the US state of New Mexico, started the Trawalla Orchard in Moree in the late 1960s, with many cockies at the time warning him he’d go broke.

Half-a-century on, Stahmann Farms is now the biggest nut producer in the Southern Hemisphere, with operations in Moree and Toowoomba.

CEO, Matt Durack, says prostate cancer claimed the life of the 83-year-old last week, but his great legacy is measured in the 40 per cent of production now exported to the world.

“Deane was the mad American who found his way to Moree by 1969 where he developed 1,800 acres of pecan trees and, certainly, many people thought, ‘This will never work’,” he said.

“Over 40 years they’ve seen that ‘crazy idea’ turn into an amazing orchard and, while he did everything slightly unconventionally, the end result is extraordinary for anyone that’s been through [the operation].”

Matt Durack says Deane Stahmann’s work has helped Australia become one of the leading pecan producers in the world.

“There’s a growing industry across Australia now and the market for pecans in Australia was virtually zero when he arrived, and that included the planting of the trees, getting the irrigation system set up and figuring out how to grow them, produce them and process them,” he said.

“He also invested heavily in exposing the Australian public to pecans and how good they taste and how good they are for you.”