Four farmhands whacked a pistachio tree with sticks, and ripe nuts rained down onto tarps. The bounty seemed plentiful but the crew was unimpressed.

"Few pistachios," Albanian worker Daso Shpata, 47, said under a blazing sun on Greece's Aegina island, among leafy trees bearing clusters of the red fruit and against a backdrop of chirping cicadas.

Climate change has slashed harvests. But there were other headaches too: children disinclined to continue the family business, trees replaced with holiday homes.

"The pistachio culture that we know is no longer viable," said Eleni Kypreou, owner of the orchard on Aegina.

"If we want to save the trees, we need to decipher what they need... Otherwise it'll be something for the museum," she told AFP.

Aegina is nowhere near the biggest pistachio p

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