Gusty winds blew a tree over in Motueka, hitting a 70-year-old woman from behind.
The Nelson-Marlborough Rescue Helicopter went to the scene, where the woman had been working in a paddock.
A spokesperson said it appeared the tree had been blown over in the wind and struck the woman.
She was treated at the scene by St John, and transported to Nelson Hospital in a serious but stable condition.
She suffered serious injuries to her leg, chest and back.
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