Arguably, man-kind has survived much longer with gathering and swidden agriculture than it will using modern intensive industrialized farming. The books in this list go to the roots of indigenous knowledge in plant-use and hill farming. Plus one of the books tells you the mystery why hill-farmers need to understand prime numbers.

John Anderson:

On a few plants from Yunnan

Edward F. Anderson:

Plants and people of the Golden Triangle

Ethnobotany of the hill tribes of northern Thailand

A detailed study of plant use and agriculture of the so-called hill tribes of Thailand that equally applies to the traditional farming techniques of Yunnan's minorities, well illustrated.

Hu-Yin Huai and Sheng-Ji Pe:

Plants Used Medicinally by Folk Healers of the Lahu People from the Autonomous County of Jinping Miao, Yao, and Dai in Southwest China

A case study of medicinal plant use by the Lahu (or Kucong) of Zhemi township in Jinping county.

Yin Shaoting:

People and Forests

Yunnan Swidden Agriculture in Human-Ecological Perspective

Slash-and-burn agriculture is commonly seen as a most destructive form of farming. Yet, if it is so destructive, why have humans survived for thousands of years with it, while modern intensive farming is threatening to destroy earth within a few hundred years? This book restores swidden agriculture to it status as the most appropriate farming method in the mountains by analyzing the techiques of the hill-farmers to minimize their impact on the environment.

Francis Kingdon Ward:

On the Altitudinal Limits of Plants in North-West Yunnan