The woman stood at her back door and screamed to divert the bear's attention from the dog. She told police the bear then charged her.
"The bear growled and was very aggressive and tried to come inside of her back door," Maricelli said. "She was able to stop the pursuing bear by improvising."
The bear took a swipe at her with its paw and tore her jeans. The woman jumped back and grasped the nearest object on her kitchen counter inside the doorway - a 12-inch-long zucchini she had harvested earlier from her garden.
She flung the zucchini at the bear from a distance she estimated to be 3 feet. The vegetable bopped the bruin on the top of its head and the animal fled, Maricelli said.
State wildlife officials were searching for the bear on Thursday. Radio station KGVO in Missoula first reported on the attack.
The woman received only minor scratches that did not require medical attention, though she was going to get a tetanus shot on Thursday as a precaution, Maricelli said. Police did not release her name.
The woman also planned to take her collie to the veterinarian. The dog didn't appear to have any bite wounds, but was a bit shaky on Thursday, Maricelli said.
"I don't know if it tried to bite him, but it rolled him around a little," he said.
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