In the latest raid, on Sunday, thieves also broke a large branch on an old plum tree, presumably as they were climbing up to reach the higher fruit.
Ms Bigwood said Heritage NZ discouraged people from climbing the trees, even if they weren't taking fruit, because some were historic in their own right. One of the pear trees had been planted in the 1830s, making it only a decade younger than the nation's oldest fruit tree, across the road at the Pear Tree Restaurant.
She believed the fruit was being sold at markets or on roadsides, because it was too much for any one person or family to eat.
In past years the Stone Store had sold hundreds of jars of jams and jellies, made with heritage fruit from the mission station's own orchard. It wasn't a big money-spinner, but visitors liked to take home a taste of Kerikeri history.
"The money goes towards looking after the buildings. It's not a huge commercial empire by any means, but it all helps," she added.
The Honey House Café, behind Kemp House, also liked to serve treats made with fruit grown on-site, such as citrus slice and lemon posset, an old-fashioned pudding. None of that was possible if there was no fruit left.
The orchard was safe while staff were about, from 8.30am to 5.30pm, but she appealed to locals to keep an eye on the property in the evening and early morning. Anyone who saw raiders filling tubs or bags with fruit should was asked to note vehicle registration, and take a photo if possible.
On February 4 a witness saw two young men in a white van filling large tubs but was unable to get their licence plate. Kerikeri police have been notified.
