Last year, executives at organic cereal maker Nature’s Path Foods Inc. grew so frustrated with organic-grain shortfalls that they took a radical step: They bought a farm.

The three-decade-old Canadian company plunked down more than $2 million for 2,800 acres of Montana cropland, part of an effort to seize greater control of its supplies of wheat, oats and other ingredients. “We just want to secure our own future,” said founder Arran Stephens.

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