Oak has been selected as the national tree of the United States possibly because of its majesty and immortality in the landscape. Oaks occur naturally in vast numbers in each of the forty-eight contiguous states but Idaho, though cultivated oaks growthere. More than sixty oak species are native to the United States and Canada, and more can be found in Mexico.Quercus alba, white oak, is a dominant tree in many landscapes. It lives for several centuries under favorable conditions, becoming more massive and picturesque with time. The U.S. national champion white oak was the famous Wye Oak, grownin its own parkin Maryland, until a storm brought it down in 2002. It was 80 feet tall with a canopy that spread more than 100 feet, and its huge limbs were supported by a 10 foot in diameter hollow trunk. White oaks show the classic rounded outline used to characterize oak leaves in art. The leaves emerge white in the spring, turn green as they expand to about 7 inches long. In the fall they turn crimson. Although this tree is not cultivated as bonsai, its natural range is a square with points at Minneapolis, Min-nesota; Augusta, Maine; Brunswick, Georgia; and Houston, Texas. Several other white oak species are common on the west coast. Garry oak, Quercus garryana, is the white oak of the Pacific Northwest ranging from northern California north into western Canada. Valley oak, Quercus lobata, and blue oak, Quercus douglasii, are common in California. Quercus grisea, commonly known as the gray oak, shin oak, or scrub oak is native to the mountains of the southwestern United States and northern Mexico.
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