A rare species of macadamia trees has been found near Rockhampton in Queensland, thanks to a keen naturalist and some handy satellite imaging software.
Thirty-seven jansenii trees were located by Keith Sarnadsky, a retired cane Farm Manager. Jansenii are the smallest native Australian macadamia species, producing small, bitter nuts. Until the discovery, it was thought that there were only around 90 jansenii trees left in the wild.
“It was just a matter of looking for specific details like the colour of a new flush of growth and the habits of the known plants we had,” said Mr Sarnadsky.
“I just looked in tributaries of Granite Creek and worked our way upstream, and I think the first group of trees I found was about roughly five kilometres from the first population.”
The discovery is the second of significance for Mr Sarnadsky, who, in 1983, made the initial discovery of the jansenii species while bushwalking near Agnes Water in Queensland. Mr Sarnadsky was one of four men who had met through a local native plant society in Bundaberg.
“The day that they were found, we had been up on top of the range for most of the day and when we descended down back towards to Bruce Highway. We pulled up there and we walked up that particular creek because it was a nice little creek. That’s when Ray found them.”
Looking for new and rare plants is some what of a passion project for Mr Sarnadsky.
“It’s a good drive from home … and it’s a rough place to take your car into and there’s a lot of strenuous walking through vine scrub,” he said.
“So yes, I’ve got a personal commitment to it.”
Protection a Priority
The Australian Macadamia Conservation Trust have been particularly pleased by the recent discovery. The jansenii species has been listed as endangered for the last twenty years, and came under significant risk in 2018 when a number of bushfires threatened the area.
“The fires were withing 10 kilometres of the jansenii population and that’s the kind of catastrophe we’re scared of,” said Denise Bond from the Australian Macadamia Conservation Trust.
“If it had burnt up the valley they could well have burnt the entire population.”
Cat’s claw creeper – a woody vine and aggressive weed – is another threat to the jansenii macadamia. Given the fragility of the species, several measures have now been implemented to protect and preserve the trees. Cuttings from 42 plants were taken five years ago and planted at Tondoon Botanic Gardens at Gladstone. The Australian Macadamia Trust have also established populations in two locations similar landscape and climate features.
Trees for the Future
According to Ms Bond, developing the jansenii could be valuable for the commercial macadamia industry in the future.
“[Jansenii are] small trees rather than big trees that are harder to manage in orchards. So, I think that’s one way jansenii may prove useful to the industry. But also, it’s just valuable as an individual unique species of the Australian Biodiversity.”
Australian Macadamia nut growers have been experiencing growth in recent years as demand from Asian consumers continues to increase.