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The Institute for Ethnobotany and Zoopharmacognosy (IEZ) is a private knowledge centre (SME) for medicinal and edible wild plants.
It was founded in 1995 by Tedje van Asseldonk, ethnobotanist and Arend de Haas, ethologist. Since 2003 Tedje van Asseldonk and Herman Albers are co-owners.


– cooperates with various educational and scientific institutes;
– is based in the Netherlands and has it’s core of activities in Europe;
– is consulted by farms, ngo’s, research institutes, education institutes and private companies for advice, field work, trainings, documentary work, project management and desk top studies.  


To study and promote an optimal use of wild medicinal and edible plants by humans and animals.
Optimal = with respect for animals and the local vegetation; promoting always an increase in biodiversity; sustainable harvesting and system approach in land and animal management; respect for local farming traditions and folk medicine; an open mind for different paradigms.

Ethnobotanical science should not look for patents to sell but try to strenghten local traditions and empower people that use them. We support open science / open research.