Importance, Tools, and Challenges of Protecting Trees

Trees are the most important landscape architects of our planet, not only in forests but also in countless other ecosystems, including human-fabricated habitats. Due to their significance in the majority of terrestrial ecosystems, trees play an important role in maintaining biodiversity and providing food and habitat for countless microorganisms, fungi, climbers, invertebrates, and vertebrates. Trees are also indispensable for the development of human societies and are important for our survival today and in the future. Trees therefore have an inestimable scientific, economic, social, cultural, and aesthetic value. In addition, they were and are playing an essential role in myths, rituals, and cultures of nearly all indigenous and modern societies. Despite these facts, the protection of trees is insufficient, both globally due to climate change and deforestation, but also locally, for example in the big cities through deterioration of soils or improper care. In industrialized countries, only recently has the need for targeted protection efforts for tree species or even for individual trees been recognized. Our review starts with the differentiation and definitions of forests and trees. Furthermore, we present the main categories and subcategories of trees, each of them possessing different functions in their ecosystems and for human societies and thus needing specific legal protection measures. The second part of our review presents the most important tools for improving the protection of trees. On the one hand, there exist a series of international initiatives, conventions, and agreements, and on the other hand, there are numerous legal tools, such as red lists, lists of protected species, and legislation for the protection of monument and habitat trees. The main challenge of the 21st century is to find a solution to make the development and growth of modern human societies compatible with the protection of natural resources such as forests. The large number of tree species, as well as the large proportion of threatened tree species, makes this problem even larger. Finally, the most recent and controversial approach of attributing trees the rights as legal persons is discussed.