THERE is a sweet smell filling the lungs of people around Bundaberg, but what is it?
Is it the sweet smell of sugary goodness from the sugar factory or the beautiful flowers in full bloom for spring? Not this time.
It's the smell of hundreds of thousands of macadamia trees which have gone to blossom a little early this year.
Which has left scientists and farmers racing the clock to crack the secrets of Australia's finest nut following the premature arrival.
Macadamia trees begin to flower across plantations starting in Bundaberg then drift south along the eastern seaboard of Queensland and New South Wales to Nambucca.
The blossoming, the first stage in the macadamia growing cycle, gives researchers a short window to undertake new research into pollination to boost the size and quality of the macadamia harvest.
Australia is the world's largest commercial producer of macadamias, contributing more than 30% of the global crop.
And Bundaberg is leading the way to become the largest macadamia growing region by the end of the year, producing more than 40% of this.
A forecast by the Australian Macadamia Society said this year's crop was on track to reach 46,750 tonnes in-shell, up four percent from last year.
The abnormal weather conditions meant blossoming began earlier than usual this year, signalling a longer growing season with the potential to make a promising harvest for Australia's macadamia farmers if favourable conditions continued.
During this year's blossoming, scientists and pollination experts are working with more than 60 leading Australian macadamia farms on research including self- and cross-pollination techniques as part of an extensive research and development program for Australia's biggest home-grown food export.
Less than 1% of flowers become nuts and a cluster of 40 to 50 flowers produces between four and 15 nutlets, which eventually ripen into nuts.
Despite originating in Australian rainforests more than 60 million years ago, maximising macadamia harvests through advances in pollination techniques has proved a tough nut to crack for the young but fast growing commercial industry, exporting approximately 70% of all macadamias to more than 40 countries around the world.
According to pollination scientist Brad Howlett bees may hold a key there was no "one-size-fits-all” answer, with the effectiveness of pollination methods largely depending on the breed of the tree.
"While we are in the early stages of our study, initial findings have all alluded to the fact that both honey and stingless bees do add a certain degree of value to pollination, regardless of the type of macadamia trees,” Mr Howlett said.
Cross-pollination, using bees and insects, has also delivered success with one grower reporting an increase in product using cross-pollination techniques, compared to self-pollination.
The short time frame the smell will linger in the air around the city is due to end by the end of the month.