Thinner plastic allows the soil to heat up better but also tears more easily. Use plastic with a thickness of 1 to 4 mils for best results. Fill in the ditch around the perimeter with soil to hold the plastic in place. You may also wish to add rocks to the edges to help hold down the plastic.
The didgeridoo is a wind instrument traditionally made from the trunk of termite hollowed eucalyptus trees from Australia (like the one pictured at left, which is being played by our mate Lewis Burns).
While playing Didgeridoo, traditionally Aborigines mimic the sounds of their surroundings. These sounds can be mixed with droning to create rhythms, which is how the Didgeridoo is used as a rhythm wind instrument. The Kangaroo Hop.