Australia’s Wild Macadamias… a Rare Gene to Cope with Climate, Illnesses

While grown in huge numbers commercially, macadamias are a vulnerable crop. A group of wild Australian nut hunters is seeking to change that, according to The Guardian. Ian McConachie has always been partial to a macadamia nut. As a boy in Brisbane in the 1940s he used to climb fences to steal them from people’s back yards. “We’d put them in a little hole in the concrete under the house and hit them with a hammer.” Now 90, he has spent much of his life devoted to the nut, including developing a tree that has raised $2 million in royalties for the Macadamia Conservation Trust, which seeks to preserve this scrappy rainforest plant. Today macadamias are a $2 billion global industry, grown in industrial quantities in subtropical climates in Hawaii, the Americas, Africa and Asia. But there was a time when Aboriginal people traded them for rum and tobacco with the white settlers here on this country. “It is the world’s finest nut,” McConachie said. “It is an Australian icon and our only native plant that has become a commercial food.” A couple of kilometers from here lives Macadamia integrifolia, which genetic testing has shown is the genesis tree of 70% of macadamia trees grown commercially around the world. There are three other species: M tetraphylla is also grown commercially, while M ternifolia and M jansenii are almost inedible, wild and rare. Macadamias have been cultivated commercially since the 1920s, starting in Hawaii. Australia didn’t start commercial production until the 1960s. Only two to three generations out of the wild is “terribly young in the world of horticulture”, McConachie said. “So we simply don’t know what the potential of the wild macadamia tree is.” All four macadamia species are native to a tiny patch of Australian subtropical rainforest in south-east Queensland and northern NSW. “Which is pretty much where everyone wants to live,” said Denise Bond, executive director of Wild Macadamia Conservation. “They [the trees] like expensive real estate, which makes them incredibly endangered because we’ve got so little rainforest left.” Wild trees may hold the key to the next generation of climate- and disease-resilient nuts. McConachie said for commercial macadamia farming, “one of the very few things Australia has got going for it is the wild trees and their genetic potential.” But more than 80% of the habitat that these trees evolved in over 120 million years is reduced to remnant now. One of the macadamia species, M jansenii, is seriously endangered, so rare “a bushfire could totally wipe them out,” McConachie said. Their locations are kept secret to protect them. While the nuts are too bitter to eat, “it could be a major tool in terms of climate change because it is so hardy.” The other three species are listed as threatened or vulnerable. McConachie has spent decades walking the remnant rainforests not far from where he lives, to find and document wild macadamias in situ. In August, he and fellow macadamia conservationist Russell Bennet took The Guardian on one of their hunts. Bennet, a Kabi Kabi man, custodian and elder, who is driving, is known for his ability to spot them. “It’s some genetic ability handed down through the ancestors, I reckon,” he said. First Nations Australians, though, have received vanishingly little financial benefit from the nut’s global popularity. When he finds a new undocumented tree, Bennet said: “it’s almost like finding gold. You can go through a lot of rainforest and not see one.” Except in September, when they flower and put on a show. The rest of the year, their dark leaves retreat into the rainforest, easily overlooked. In 1981, McConachie and his wife, Jan, bought a rundown dairy farm near Wolvi. He flirted with other trees, mangoes, lychees, stone fruit, but quickly came back to his great love. After an extensive selection trial, he found a particularly hardy and accommodating tree, named it MCTI and secured planter breeding rights. “It has sold about a million and a half trees,” he said, “and raised about $2 million in royalties.” All of that has been donated to Wild Macadamia Conservation. “We’re probably all a bit eccentric,” he said of the group, “but we’re passionate about the need to conserve the wild genetics.”