Most of Europe’s trees are similar to those in North America, but these are related by genus and are not members of the same species. This is true of oaks, maples, ashes, elms, birches, beeches, chestnuts, walnuts, apples, and hornbeams as well as conifers. Some of the native tree species of Europe have been brought to North America and have become a part of the American forest. The sycamore, for example, is the same species in North America as in Europe. The sycamore is a long-lived tree, some sycamores that were planted in North America during the colonial era are still alive. The mountain ash, with its bright orange berries, is another tree from Europe (where it is known as the rowan) that has immigrated to North America. The horse chestnut is yet another tree native to Europe that has long been settled in North America.
Among the evergreens, the Norway spruce has been widely planted and now seeds itself in North America. The Scots pine has been widely planted in North America; many Christmas trees sold every year in the United States are Scots pine. The European larch has become popular with the U.S. forest industry because it is suited to reforestation afterclear-cutting.
Some North American species have made the opposite journey: Much of Scotland has been reforested with the Sitka spruce, a native of the Pacific Northwest. Another Native American evergreen that has made the trip to Europe is the white pine, known in Europe as the Weymouth pine. Plantations of white pine have been set up all over Europe, because Europe did not have a soft pine, and the wood of the white pine is easily worked.