Queensland macadamia growers say there are early signs more record harvests could be on the cards, and native bees are being credited with some of the success.

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The Australian Macadamia Society said growers were on track for a record harvest of 47,000 tonnes-in-shell this year, up from a bumper crop of 43.600 in 2014, and the current blooming indicates 2016 could be a record-breaker too.

Suncoast Gold Macadamias technical officer, Chris Searle, said lots of flowers evenly distributed through the trees can predict a good year.

"That means that those flowers are going to get plenty of energy from all the different leaves throughout the tree."

Macadamia trees flower differently from other nuts like almonds or fruit trees, in that rather than producing single blossoms for nuts, the tree grows racemes; 10 or 15cm stalks that can carry hundreds of tiny flowers.

Mr Searle said the racemes allow the native tree to manage its flowering and subsequent nuts depending on the quality of the season.

Suncoast Gold Macadamias technical officer Chris Searle says racemes contain hundreds of flowers, but set only a few nuts ( Kallee Buchanan )

"Sometimes on a raceme we'll get up to 40 or 50 little nutlets set, but the trees set many, many more nuts than they will actually hold and over the course of the season we will lose a lot of those," he said.

"In late October, early November we have what's called a nut shedding period and we can lose 70 or 80 per cent of those little nuts that were set early."

But he said that mechanism allows the trees to produce the optimum number of nuts, based on the tree's health.

"Giving them the right amount of fertilisers, right amount of water and ensuring that you've pruned your trees so you get very good light distribution throughout the tree will give you the optimum growth," he said.

"If you have optimum growth them you generally get optimum flowering and optimum yields.

"Generally everyone's pretty positive about the upcoming season, the trees are looking very very healthy and very happy, and that's really the key to this whole productivity of the region is having good, happy, healthy trees and they will perform for you as a consequence."

Mr Searle said cross-pollination, where bees jump from tree to tree and across different varieties dropping pollen on the flowers, is a critical step in the process.

"When they move pollen from one to the other, the pollen then moves on to the end of the flower, grows down, and fertilises the little egg at the base of the flower and that will then develop into a macadamia within a week," he said.

"In six month's time we'll be harvesting those nuts."

Native bees for a native nut

Kin Kin Native Bees pollination consultant Chris Fuller has been consulting on macadamia trees for about 20 years.

He said there were signs the bees were contributing to the record harvests.

"From very early on I started to notice how active the native stingless bees were in macadamia farms that were flowering," he said.

"Over the years I started to collect hives and propagate them up through a splitting process, which helps us duplicate hive numbers each season.

About a week after the flowers are fertilised, macadamia nutlets form on the raceme. ( Kallee Buchanan )

"Now we're getting hive numbers up to a point where we can do some decent trial work and we're starting to see the correlating crops increase by the use of the native stingless bees."

Mr Fuller acknowledged there were many factors that went into a good harvest, but he believed the bees played a significant role.

He said when it came to cross-pollination, the small native bees were experts at getting into the small, delicate flowers, which contributed to the creamy, buttery flavour of the nuts.

"[The bees] are extremely interested in collecting pollen, pollen is the protein that bees use to feed their babies," he said.

"The stingless beehives are coming out of a long winter, it's a time when they want rapid expansion of the brood and bee numbers within the hive.

"When it comes to spring, they want to burst of bee numbers and to do that they're collecting the pollen from the macadamias because it's got a very good protein content."

Mr Fuller said that burst of activity encouraged the bees to visit as many trees as possible, resulting in cross-pollination.

"We've found that the macadamias are extremely responsive to cross-pollination," he said

"In fact a lot of the trial work's shown that generally up to 92 to 95 per cent of all the nuts coming off an orchard are cross-pollinated nuts.

"What you want is that bee to hop from one variety to another, brushing a bit of pollen off itself and into stigma of the [receipting] flower and you get good cross-pollination of that particular flowers and a lot better chance of producing a big healthy nut."

The blossoming and pollination of macadamia trees starts in Bundaberg at the end of August, then moves south along the eastern seaboard of Queensland and New South Wales to Nambucca, where it will finish around late September.