Firefighters say nearly $100,000 of alfalfa went up in flames Thursday after a large stack spontaneously combusted in Twin Falls.
Rock Creek Fire District spokesman Taylor Hunsaker says the stack, which was made of 480 tons of hay, will burn for almost a week.
Craig Giles, who grew the alfalfa, says he hired a custom operator to bale it. He says the bales were stacked with enough distance between them to allow moisture and heat to escape.
Agricultural officials say spontaneous combustion is common in haystacks because they often have trapped moisture in them. Once the moisture mixes with enough heat, the stack will combust.
Officials recommend taking moisture samples rather than feeling by hand when baling hay or alfalfa.