(I also posted this over on the Railway Bull Shippers Group)
Way back when, the practice used to be that bee colonies were established (starting with the queen) in the South where it was warm in the Spring, and then sent up to Canada so that when things warmed up and the clover season started up there, they could hit the ground running (buzzing?). At the end of the season the beekeepers became beekillers and snuffed the full hive off and took the remaining honey as it was too much trouble to keep them alive in the cold north winters.
The bees being transported are in what are called Nucs (nucleus), just a queen and a big slug of worker bees and a feeder of sugar water (usually canning syrup). They are basically screened boxes that have to be stacked in the car in specified configuration to allow ventilation (think of big squares that are open in the middle too). Trucks took over the job as soon as the north-south highways were improved.
RJ Dial (also a Beekeeper)