Final answer:
Swiddens are part of the traditional farming practices of the Yao in Thailand.
Step-by-step explanation:
For the Yao in Thailand, swiddens are part of their traditional farming practices . Swiddens, also known as slash-and-burn agriculture, involve clearing land by cutting and burning vegetation, and then planting crops in the nutrient-rich ash. The Yao people have been practising swidden agriculture for centuries as a sustainable way to cultivate their crops in the hilly terrain of northern Thailand.