MDU Resources Group Inc., an energy and construction company, said Friday it acquired Yarbrough's Dirt Pit Inc., an aggregate supplier and ready-mix concrete producer.
Financial terms were not disclosed.
Bismarck, N.J.-based MDU Resources said Yarbrough will become part of Knife River Corp., its construction materials and contracting unit.
MDU said the deal will help its 2008 earnings and strengthens its construction materials business.
Shares fell 12 cents to $30.18 in aftermarket trading.