MINNEAPOLIS (AP) -- Minnesota apple growers worry that a recent cold snap could kill new buds on their apple trees after early warm weather this spring.

Growers are trying to warm their orchards with bonfires and by spraying trees with special solutions. Others are using wind machines and even helicopters to drive cold air out and warmer air down.

University of Minnesota researcher David Bedford says that at 28 degrees trees could lose 10 percent of their buds. At 25 degrees as much as 90 percent. Some growers have seen temperatuers well below that this week.

Experts say it will be several weeks before they know how much damage is done to the state apple crop. They say prices probably won't go up for customers because larger national crops have not been threatened.

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