Heat has been used to control pests and weeds since the very beginning of agriculture.
Until today fields are burned down in order to create and improve soil fertility. Ancient civilizations such as the Indians or the Egyptians also systematically used sun radiation on irrigated agricultural soil to disinfect and revive arable land.
At the end of the 19th century the application of heat for soil sterilization is documented whereas two methods were developed simultaneously: the roasting of agricultural soil over an open fire and the steaming of soil with water vapor.
At the beginning steam was induced into the soil through drainage pipes. Later steaming hoods and harrows were used. The development of heat resistant sheets made the treatment of large areas with steam easy to handle.