Does anyone have experience with making a soil sterilizer?

[RSKY]

When I was a kid and my dad prepared a "plant bed" for tobacco seed he would drag out all the trees and brush that had fallen in the woods. He and my uncles would pile it up and burn for a couple days. As soon as the soil cooled they would rake the chunks out, spread fertilizer, then very carefully sow the tobacco seed. The bed would be covered with tobacco cloth which was tucked in under logs rolled to the edge. The large logs kept the cloth off the new plants. The cloth kept seeds from being blown in.