The owner and staff of a Hawke's Bay vineyard have been stunned by a night-time attack on their vines which damaged about 500 plants.
The manager, who did not want to be identified, said the incident destroyed about $10,000 worth of fruit.
"They know viticulture because they have done what they know will harm the plants," he said.
He said it appeared cutting tools used in the grape-growing industry had been used.
Damage, spread over a half-hectare area, was discovered yesterday and appeared to have been carried out overnight.
The manger said the attackers damaged three grape varieties, merlot, pinot gris and chardonnay.
It would take a year for the damaged plants, which had been in the ground about four to five years, to recover.
"It is bizarre and it's just gutting. It's been a lot of work getting to this stage and everything was looking good.
I have no idea why anyone would want to do this or if anyone's got a grudge for some reason.
"It's such a spiteful thing to do."
The owner of the property had been growing there for about a dozen years and had not experienced any other problems.
Taradale Police Senior Constable Pete Gimblett described the attack as "gutless".
In the 20 years I've been with police I've never come across something like this," he said. "(Management) are scratching their heads as they have no idea why they have been targeted."
Mr Gimblett said the culprits would have been in the vineyard for up to two hours.
"They have covered a significant area on foot."
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