The Manual on Uniform Traffic Control Devices (MUTCD) is approved by the Federal Highway Administrator. as the National Standard in accordance with Title 23 U.S. Code, Sections 109(d), 114(a), 217, 315, and 402(a), 23 CFR 655, and 49 CFR 1.48(b)(8), 1.48(b)(33), and 1.48(c)(2).
The dominant vegetation types are grassy prairie and grass steppe in which numerous species of the grass genus Stipa are particularly conspicuous. Pampas grass (Cortaderia selloana) is an iconic species of the Pampas. Vegetation typically includes perennial grasses and herbs.
Though the Pampas have a gradual slope northwest to southeast, from 1,650 feet (500 meters) to 66 feet (20 meters) above sea level, most of the region appears flat. The Pampas is a distinctive geographical feature of South America and covers a staggering 295,000 miles (760,000 square km). It is divided into two zones: the western dry zone is largely barren with large saline fields, sandy deserts, and brackish streams. In the east is the humid sections of the Pampas, a much smaller area with water sources.