Nearly 300 millions people live in forests, and 8 of 10 land species.
Of the 265,000 species of flowering plants that have been identified on this planet, only 0.5% of them have been studied in detail for chemical composition and medicinal value. In fact, modern scientists only know the chemical composition of less than 5% of the flora in the rainforest (Jackson, 1989). However, indigenous peoples who live in the rainforest can identify specific uses for 49-82% of the trees in their local environment (Weeks, 2000).
For thousands of years, indigenous groups have extensively used forest plants for their health needs. They have experimented with a wide range of plants. The peoples of Southeast Asian forests used 6,500 species, while Northwest Amazonian forest dwellers used at least 1,300 species for medicinal purposes. The success rate for discovering medicinal plants with traditional uses is high because rainforest peoples, notably shamans, have been experimenting with various combinations and dosages for generations.
Poh Kao publication:
This botanical inventory is the result of a unique collaboration between Cambodian institutions and international NGOs to raise awareness about forest protection and show the value of the remarkable biological diversity of the Veun Sai – Siem Pang Conservation Area (VSSPCA) in Northeastern Cambodia.
Together with the Cambodian department of traditional medicine and the Association of Khmer Healers, we worked to list over eighty medicinal plants of the VSSPCA used by local traditional healers.
Dr Hieng Punley from the Ministry of Health 
Dr Sunna
As hunter-gatherers and farmers, the local population of the area significantly relies on local plants for their nutritional and medicinal properties. However, the genetic resources of these plants offer opportunities for sustainable use internationally, including opportunities for development and marketing of pharmaceutical and cosmetic products (nearly 80% of drugs launched in the past five years to fight different forms of cancer were directly derived from natural products).
The data of this botanical inventory was compiled in 2011 by Poh Kao.
Poh Kao, Tigers and Men 