South Texas

South Texas is a region of the U.S. state of Texas that lies roughly south of -- and sometimes including -- San Antonio. The southern and western boundary is the Rio Grande, and to the east it is the Gulf of Mexico. The population of this region is about 4.67 million according to the 2013 census estimates. The southern portion of this region is often referred to as the Rio Grande Valley. The eastern portion along the Gulf of Mexico is also referred to as the Coastal Bend.

There is no defined northern boundary, although it is believed to be at the city of San Antonio and from an east to west line extending from the Rio Grande near Maverick County to the Gulf of Mexico, but turning southeast at or near Lavaca County, and continuing towards the Gulf of Mexico to separate it from East Texas and Southeast Texas. The Rio Grande serves as the western and southern boundaries and separates Texas from Mexico. The eastern portion of South Texas is bordered by the Gulf of Mexico. This region of Texas consist of 41 counties. South Texas terrain is flat, lying on the coastal plain. South Texas is so vast, there are even subregions. The very southern tip of South Texas, called the Rio Grande Valley, has fertile soils and is known for its citrus production. The eastern portion of South Texas is often referred to as the Coastal Bend; here, coastal salt marshes, estuaries, and wetlands are scattered. The western and central parts are known as the South Texas Plains or the brush country. Mesquite trees and crop fields dominate the land.

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