The range of this tree covers at least a million square miles, and all or part of every state east of the Mississippi river and west of it from Nebraska to Texas. It is reported cut for lumber in thirty states. The various ashes are lumbered in thirty-nine states. Ash does not occur in pure stands but is scattered in forests of other species, sometimes growing in small clumps. It is difficult to name an average size for the tree, because climate and soil control the growth over a large area where conditions vary. Trees 120 feet high and six feet in diameter are said to have stood in the primeval forests in the lower Ohio valley; but logs four feet through are seldom seen now. Trees seventy or eighty feet high and three in diameter are above the average in any region where this tree is now lumbered. Some of the old planted trees of New England are five or six feet through, and are finely proportioned, but growing as they do in the open, they have larger crowns than are found in forest trees. All species of ash have compound leaves, and those of white ash are from eight to twelve inches long. The under sides of the leaflets are white, and some persons have this fact in mind when they call the species white ash, while others refer to the bark, and still others to the wood. It is a characteristic of the tree that most of the leaves grow near the ends of the limbs. For that reason the crown appears open when viewed from below, and the larger limbs and branches are naked. The leaves demand light, and they arrange themselves on the extremities of the limbs to get it. When the tree is crowded, it sheds its lower limbs and its crown rises rapidly until it reaches abundance of light. This produces long trunks in forests. The boles are often not quite straight, but have several slight crooks, yet keep close to a general perpendicular line. That form is due to a peculiarity of growth. The leading shoot of a growing ash has more than one terminal bud. If a side bud pushes ahead, the stem leans a little in that direction; next, a bud on the other side may gain the ascendancy, producing a slight lean for a few years in that direction; or two side buds may develop simultaneously, causing a forked trunk. Mature trees often carry the history of these peculiarities of growth.