INDIANAPOLIS (AP) — Several state agencies are warning Indiana motorists that harvest season has started and they should expect to see slow-moving farm equipment on roads.

Lt. Governor Sue Ellspermann said in a statement Wednesday that drivers should have patience and drive safely around slow-moving vehicles.

The Indiana state departments of Agriculture, Homeland Security and Transportation and the Indiana State Police remind motorists that some farm equipment is so wide that it takes up most of a roadway. They say if a vehicle is traveling at 55 mph and a tractor is moving at 15 mph, it only takes five seconds to close a gap the length of a football field.

By law, farm equipment must have the nationally designated slow-moving vehicle sign — a red triangle-shaped reflector — to warn oncoming drivers.