Dendrology (Ancient Greek: δένδρον, dendron, "tree"; and Ancient Greek: -λογία, -logia, science of or study of) or xylology (Ancient Greek: ξύλον, ksulon, "wood") is the science and study of woody plants (trees, shrubs, and lianas), specifically, their taxonomic classifications.^[1] There is no sharp boundary between plant taxonomy and dendrology; woody plants not only belong to many different plant families, but these families may be made up of both woody and non-woody members. Some families include only a few woody species. Dendrology, as a discipline of industrial forestry, tends to focus on identification of economically useful woody plants and their taxonomic interrelationships. As an academic course of study, dendrology will include all woody plants, native and non-native, that occur in a region. A related discipline is the study of sylvics, which focuses on the autecology of genera and species.

Pine Spruce Larch Juniper Aspen Hornbeam Birch Alder Beech Oak Elm Cherry Pear Maple Linden Ash

In the past, dendrology included the study of the natural history of woody species in specific regions, but this aspect is now considered part of ecology. The field also plays a role in conserving rare or endangered species.^[1]