OCR Text |
Show BASIS OP AMERICAN HISTORY [ 1500 gigantea), which, though neither the tallest nor the broadest, is conceded the distinction of being the largest in the world, rising to a height of from two hundred and seventy- five feet . to nearly four hundred feet, with a diameter of twenty to thirty- five feet, and attaining a great age. All these are conifers. Hardwoods are, however, not entirely lacking, the most valuable in the coast region being the cotton- wood and the large- leaved maple. In the interior the forest is less continuous. The Columbia basin contains a fair supply of timber, especially the western larch, and the eastern slopes of the Sierra Nevada bear valuable pines. ( In the Rocky Mountains of Colorado, at elevations of from eight to ten thousand feet, a spruce ( Picea Engel-manni) grows luxuriantly, and yellow pine, red fir, and white fir are plentiful at lower altitudes. A similar vegetation follows the high mountains as far as western Texas, where the pines again become important. Along the northern boundary of Mexico a fusion takes place between the floras of the adjacent portions of the Atlantic and Pacific belts. The trees are comparatively small, the mesquite extending over a very wide area, while east of the Colorado the giant cactus is one of the most striking of the plants. This vast extent of forest has had a vital bearing upon the settlement and further development of the country. VTo the pioneer it was at once a blessing |