A Minnesota turkey farmer will testify in Washington, D.C. on Thursday as part of a Senate investigation into propane shortages this winter. John Zimmerman of Northfield, past president of the Minnesota Turkey Growers Association, will be one of several witnesses telling how propane shortages drove up prices for him and others who rely on propane to heat their homes, businesses, and livestock and poultry barns.

Propane suppliers started the winter with lower-than-usual levels of the heating fuel, and couldn't catch up as below-zero temperatures persisted throughout much of the Upper Midwest. Average propane prices nearly doubled across the nation in early February, and spiked even higher in Minnesota where 250,000 homes, businesses and farms use propane as their main fuel for heat.

Minnesota Gov. Mark Dayton declared a peacetime state of emergency in late January because of severe propane shortages, and the state set up a hot line to address propane-related issues. Minnesota also received an additional $16 million in federal funds to assist homeowners through the Low Income Energy Assistance Program.

Propane supplies and prices returned to normal around March 1, said Minnesota Propane Association executive director Roger Leider. One of the main reasons was that the high mid-winter prices drove many businesses to switch to cheaper fuels if they had the option to do so, he said, the decreased demand caused propane prices to ease.

Zimmerman will testify before the Senate Energy Committee that is looking at the causes of the propane supply problems and ways to prevent future shortages. His invitation was arranged by Sen. Al Franken, a committee member who also pressed federal energy and transportation officials this winter to bring more propane to hard-hit Minnesota areas by truck and pipeline.