The world loves almonds, so Californian farmers planted some 77 million almond trees, enough for California to become the world's biggest producer – but there aren't enough bees anymore. Honeybees, you see, keep dying from mysterious illnesses, meaning bees are now trucked from all over the U.S. to California each year in the winter in order to pollinate all those almond trees. Farmers used to pay $50 per colony, now the average price is closer to $150. A simple matter of, um, "bee-conomics".
Here's John Miller, a fourth-generation beekeeper from North Dakota, checking on his bees near Modesto, California. John runs Miller Honey Farms, one of the nation's bigger honey producers (see your supermarket for more).
The smoke has a somewhat calming effect on the bees, but naturally, when visitors pester them a little too much (especially with, say, strange machinery and flashing lights) they can become a bit prickly.