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The forests in the U.S. state of Texas have been an important resource since its earliest days and have played a major role in the state's history. The vast woodlands of the region, home to many varieties of wildlife when Europeans first arrived, provided economic opportunities for early settlers. They continue to play an important role economically and environmentally in the state. The most dense forest lands lie in the eastern part of the state in the Piney Woods region. In particular the Big Thicket region, just north of Houston and Beaumont, has historically been home to the most dense woodlands. The Big Thicket was mostly uninhabited until heavy settlement from the U.S. began in the mid-19th century, and was even used as a refuge by runaway slaves and other fugitives. The Rio Grande Valley in South Texas was home to a large palm tree forest when Spaniards first arrived, though today very little of it remains. One of the first steam sawmills in Texas was planned in 1829 in what is now modern Houston. After the Texas Revolution lumber production increased steadily such that by 1860 there were reportedly 200 saw mills in the state. The construction of railroads throughout the eastern part of the state led to boom in lumber production starting in the 1880s. The following 50-year period in which the Texas timber industry flourished came to be known as the "bonanza era". Though the growth of the industry provided significant economic benefits to Texas, a lack of regulation allowed business owners to exploit many individuals including appropriating private property and forcing laborers to accept poor working conditions and low wages. By the start of the 20th century timber was one of the leading economic engines of Texas and had become the state's largest manufacturing enterprise. Lumber barons, such as John Henry Kirby, were among the wealthiest people in the state. By 1907 Texas was the third largest lumber producer in the United States.〔〔 The subsequent clearing of fields for oil exploration and the related demand for lumber through the first half of the 20th century destroyed much of the remaining forest lands in the state. By the 1920s lumber production was in decline and the onset of the Great Depression devastated the already flagging industry. In recent times preservation efforts, such as the creation of the Texas Big Thicket National Preserve in 1974, have helped to stabilize parts of the Texas woodlands. Texas remains in the top ten timber producing states in the United States. ==Ecological patterns== The climate in Texas varies greatly across the state. Humid, rain-soaked swamps lie toward the east and desert lands lie in the far west. Woodlands, grasslands, brushland, and other ecological regions can be found in between and around the state. A prominent climatic feature of Texas is a ''dry line'' that runs north-south through its center. This line, though not entirely fixed in its location, represents a point east of which relatively moist air from the Gulf of Mexico flows freely, and west of which the drier air from the Mexican deserts prevails. The forest lands, of course, mostly lie to the east of this line though pockets of woodland can be found in the mountains to the west. Texas is periodically subjected to extreme droughts that can last several years, even as much as a decade. The most severe example in modern history was the 1950s drought that reshaped the state's economy. These drought periods are known to dramatically reduce the forests. The severe drought of 2011, for example, is estimated to have killed between two and ten percent of the state's trees. Texas forest lands can be divided into six major regions: the Big Thicket, the Piney Woods, the Gulf Coast, the Edwards Plateau, the lower Rio Grande Valley, and the Trans-Pecos mountain forests.〔Kricher (1999), ch. 6.〕〔Kricher (1999), p. 311–312.〕 East Texas is home to the Piney Woods, a vast region extending from Texas through parts of Oklahoma, Arkansas, and Louisiana. These woodlands feature many varieties of pine as well as hardwood varieties including magnolia, American Sweetgum (''Liquidambar styraciflua''), and elms (''Ulmus'' spp.).〔 Texas State Historical Association.〕 The Big Thicket is the southern portion of this region, and has historically been the most densely wooded part of the state, acting as a natural divide between Southeast Texas and coastal Louisiana. The Texas coastal region has more sparse tree growth but still contains many varieties including Southern Live Oak (''Quercus virginiana''), mesquite (''Prosopis'' spp.), and Texas Persimmon (''Diospyros texana'').〔 Texas State Historical Association.〕 The Edwards Plateau region of Central Texas contains woodlands featuring Ashe Juniper (''Juniperus ashei''), Texas Live Oak (''Quercus fusiformis''), and Honey Mesquite (''Prosopis glandulosa''). The lower Rio Grande Valley has historically been home to a large semitropical forest of Mexican Palmetto (''Sabal mexicana'').〔 Though West Texas is mostly grasslands and desert, mountainous areas in the Trans-Pecos portion, such as the Guadalupe Mountains, contain oases of forest lands featuring Bigtooth Maple (''Acer grandidentatum''), Velvet Ash (''Fraxinus velutina''), Grey Oak (''Quercus grisea''), and similar tree species.〔 Texas State Historical Association.〕 Additional pockets of forest lands include the Cross Timbers areas of North Texas in the vicinity of the Dallas – Fort Worth metroplex, as well as areas throughout the savanna and blackland prairies that lie to the west of the Piney Woods and the coastal areas. For its part the Cross Timbers region, which straddles Texas and Oklahoma, though relatively narrow, was once dense enough to have been considered a natural barrier.〔Gregg, p. 200〕 Though these woodland areas have never been a major source of lumber they have nevertheless provided firewood as well as wood for poles, railroad construction and other limited uses.〔 Texas State Historical Association.〕 Patches of original oak and hickory woodland remain in the ranchlands of eastern Texas, west of the Piney Woods, and these have been described as the East Central Texas forests ecoregion. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「History of Texas forests」の詳細全文を読む スポンサード リンク
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