Before they were the first women to become famous on the Grand Ole Opry and the National Barn Dance, The Cackle Sisters, (also known as the DeZurick Sisters) were raised on a farm in Royalton, Minnesota. To develop their unique yodeling style, Caroline De Zurik has said they simply "listened to the birds and tried to sing with the birds."
You can hear and download more tracks on wfmu's beware of the blog. I especially love tracks like "Peach Pickin' Time in Georgia","Little Golden Locket" and "Sing Hallelujah", where they seem to hit the sweet spot between their bizarre but amazing stereo-clucks and brilliantly close harmonies.