Résumé
Herbariums are particularly interesting supports whether for teaching botany and phytotherapy or for researchers. They are, in fact, true witnesses of the flora as it may have been. They are thus valuable conservation tools, especially at a time when climate change is the cause of major ecological disasters. It is therefore important to participate in their digitization in order to not only be able to keep track of them but also to distribute them to as many people as possible. Herbariums are also an opportunity to learn more about certain botanicals species. I have chosen to study here the pharmacological properties of Yarrow (Achillea millefolium L.). A common plant along the roadsides of the northern hemisphere, it has long been known for its haemostatic action. The most recent medicinals specialties use it today in their composition to relieve menstrual pain. Yarrow is also studied in the context of the development of new anti-inflammatory drugs.