Worms rise when it rains. Worm charmers try to trick worms into believing–if that’s the right word– that it’s raining. They’re not allowed to use water, or to dig the worms up. Instead they make the earth vibrate. Some play musical instruments. The more successful charmers use pitchforks, which they move in various ways (hence twanging, twickling etc.).
The world record holder is Sophie Smith, who was 10-years-old when she (with the help of an older relative) charmed 567 worms to the surface of a three square meter patch of land in a mere 30 minutes. The World Worm Charming Championships website has all the details on this year’s winners, along with a great photo gallery.