Fold mountains

Ouachita Mountains – WorldAtlas

The Ouachita Mountains are a mountain range in the south-central United States that stretches approximately 360 kilometers east to west from central Arkansas to southeast Oklahoma. The mountain range takes its name from two Choctaw words meaning “land of the great buffaloes.” The Ouachitas are a continuation of the Ozark Mountains, the two mountain ranges forming the interior highlands of the United States. The highest elevation in the chain is Mount Magazine in Arkansas, at 839 meters above sea level. The range is unique in that it stretches in an east-west direction instead of north-south like the Rocky Mountains and Appalachians. The Ouachita range is a level three ecoregion, divided into six level four ecoregions.

Where are the Ouachita mountains?

The Ouachita Mountains are one of the major mountain ranges in the south-central United States and are part of the Interior Highlands of the United States, a mountainous region between the Rocky Mountains and the Appalachians. It stretches east to west from Little Rock, Arkansas to Oklahoma, where it crosses the southeastern counties of Le Flore, Latimer, Mc Curtain and Pittsburg and ends in Atoke. The range includes the Ouachita National Forest, the oldest national forest in the southern United States stretching from western Arkansas to far eastern Oklahoma.

Geography of the Ouachita mountains

A hiker exploring the Ouachita Mountains.

Unlike the Rockies and Appalachians which stretch from north to south, the Ouachitas stretch from east to west. It stretches approximately 360 kilometers from Arkansas to Oklahoma and 80 to 90 kilometers from the Arkansas River valley to the northern margin of the Coastal Plain. The highest elevation in the chain, Mount Magazine, rises approximately 839 meters above sea level.

The Ouachita Mountains were formed in the same way as the Appalachian Mountains, during the Paleozoic Era (about 300 million years ago). The area where the chain is located was occupied by the Ouachita basin (deep ocean). The movement of the South American plate and the ocean waves caused the ocean floor to fold. The range had a much higher elevation than it is today, but erosion and wind reduced the height of the mountains and caused the Arkansas Embayment to form. Mountains lack volcanism and metamorphism, common features in an orogenic belt. The Ouachitas contain fine quartz, with Mount Ida containing some of the greatest amounts of quartz. The mountain range also contains chert, sandstone and slate.

Due to faults and folds, the Ouachitas are subdivided into smaller chains, separated by ridges and wide valleys. Mount Magazine, Ouachita’s highest peak, is part of the Frontal Ouachita Range, located in the Arkansas River Valley. This beach is different from the other sub-ranges and can be considered as an independent beach. Another sub-range of Ouachita is the Fork Range that stretches between Pulaski, Arkansas and Atoka, Oklahoma, with Rich Mountain as the highest peak at 830 meters. The Forks contains several popular sites, such as Pinnacle Mountain State Park. The Athens Plateaus are part of the Ouachitas that stretch from Arkadelphia, Arkansas, to McCurtain County, Oklahoma and include hills and low ridges. The other sub-ranges of the Ouachita chain are the Caddo, Cross, Missouri, Crystal, Tap and Zig Zag mountains.

Wildlife In La Ouachita

Flower of Ouachita National Forest
A wild flower in the Ouachita mountains.

The Ouachita region receives heavy rainfall of about 1220 to 1420 mm per year. The area is home to several tree species, including pines (loblolly and shortleaf), hickory, and white, black, postal and red oaks. Holm oaks and shortleaf pines grow in the highlands. La Ouachitas also contains the only sites in the world where maple leaf oaks grow. Plant species endemic to the region include Houstonia ouachitana, Solidago ouachitensis, and Quercus acerifolia.

The Ouachita National Forest is home to several animals, including wild turkeys, deer, black bears, gray foxes and squirrels, raccoons, and cottontail rabbits. Lakes and several streams flowing from the mountains provide habitat for over 150 native fish species. About 24 animal species that once dominated the area have become extinct due to overhunting and habitat loss. Animals include carrier pigeons, Carolina parakeets, elk, and bison.