Materia Medica, Liber I: De Plantis is the first volume of Carl Linnaeus’s comprehensive work on medicinal plants, published in 1749. This volume serves as a pivotal reference in the history of pharmacology, systematically cataloging plants and their therapeutic properties. Linnaeus’s methodical approach laid the groundwork for modern botanical classification and herbal medicine.​

In this volume, Linnaeus organizes plants based on their medicinal uses, providing detailed descriptions of each species. He includes information on the plant’s habitat, appearance, and the specific ailments it addresses. For instance, he discusses the use of Calamus aromaticus (sweet flag) for treating urinary issues and promoting menstruation. Similarly, he details the medicinal applications of Balm of Gilead, emphasizing its effectiveness in treating colic, shortness of breath, and various other conditions.​

Linnaeus also delves into the preparation methods of these plants, describing how they can be transformed into oils, ointments, and other medicinal forms. He outlines the processes of extraction and preservation, ensuring that the therapeutic properties of the plants are maintained. This practical approach reflects a deep understanding of both botanical science and medical practice.​

The significance of De Plantis extends beyond its immediate medical applications. Linnaeus’s work influenced subsequent generations of herbalists and pharmacologists, shaping the development of botanical medicine. His contributions underscore the enduring value of traditional knowledge and its integration into contemporary scientific frameworks. By preserving and systematizing the medicinal uses of plants, Linnaeus ensured that this wisdom would continue to inform medical practice for centuries to come.