Arizona: Recent hard freeze likely will be death knell for many weaker saguaros

A prolonged freeze three weeks ago almost certainly was a death sentence for some members of a prized desert species: the saguaro cactus.
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"There was a prolonged cold spell in 1971," Swann said. "Scientists working in the park at that time documented the effects and found that the freeze caused saguaro deaths. It tended to affect the oldest and the youngest ones."