DixieNational Forest is a United States National Forest in Utah with headquarters in Cedar City. It occupies almost two million acres and stretches for about across southern Utah. The largest national forest in Utah, it straddles the divide between the Great Basin and the Colorado River. In descending order of forestland area it is located in parts of Garfield, Washington, Iron, Kane, Wayne, and Piute counties. The majority of forest acreage lies in Garfield County. Elevations vary from above sea level near St. George, Utah to at Blue Bell Knoll on Boulder Mountain. The southern rim of the Great Basin, near the Colorado River, provides spectacular scenery. Colorado River canyons are made up of multi-colored cliffs and steep-walled gorges. The Forest is divided into four geographic areas. High altitude forests in gently rolling hills characterize the Markagunt, Paunsaugunt, and Aquarius Plateaus. Boulder Mountain, one of the largest high-elevation plateaus in the United States, is dotted with hundreds of small lakes 10,000 to 11,000 feet above sea level. The forest includes the Pine Valley Mountains north of St. George The Forest has many climatic extremes. Precipitation ranges from in the lower elevations to more than per year near Brian Head Peak. At the higher elevations, most of the annual precipitation falls as snow. Thunderstorms are common during July and August and produce heavy rains. In some areas, August is the wettest month of the year. Temperature extremes can be impressive, with summer temperatures exceeding near St. George and winter lows exceeding on the plateau tops. The vegetation of the Forest grades from sparse, desert-type plants at the lower elevations to stand of low-growing pinyon pine and juniper dominating the mid-elevations. At the higher elevations, aspen and conifers such as pine, spruce, and fir predominate. The Dixie Forest Reserve was established on September 25, 1905 by the General Land Office. The name was derived from the local description of the warm southern part of Utah as "Dixie". In 1906 the U.S. Forest Service assumed responsibility for the lands, and on March 4, 1907 it became a National Forest. The western part of Sevier National Forest was added on July 1, 1922, and all of Powell National Forest on October 1, 1944.