Usually a tree has two names, the common or local name and the “real name,” or scientific or botanical name, in Latin, generally used by botanists and others having a more technical interest. The generic name is used to include a group of closely related species. For example, “Pinus,” the classical Latin name for the pine tree group, includes all the species (kinds) of true pines. The secondary Latin name signifies the particular species of that tree group, as “Pinus strobus,” the scientific or botanical name for White Pine (now called Eastern White Pine). The name of the scientist who discovered and named the particular species is sometimes indicated after the botanical name, as “Pinus strobus Linnaeus.” The use of a common name for a tree quite frequently results in much confusion because of the lack of universal agreement as to what should be the proper common name of a given tree. Some trees have from 10 to 25 different common names for the same species, depending upon the locality in which the tree is found. For example, Pinus ponderosa, which covers a wide range in the western half of North America, is the scientific name for Ponderosa or Western Yellow Pine, the common names usually accepted, but it also is called Bull Pine, Black Jack and many other common names in various parts of its range. In the United States Forest Service both common and scientific names of trees are passed upon by a special committee named by the Chief Forester. However, this committee collaborates in this work with the various colleges of the country in which the science of forestry is taught. In this book both the common and scientific names approved in the latest “Check List” of this special committee are given.