117-Boston Mountains

Arkansas, and Oklahoma
14,930 sq. km (5,770 sq. mi)

Land use: About 76 percent of this MLRA is forested, mainly in farm woodlots but large tracts in Arkansas are national forests. About 16 percent is grazing land, 6 percent is cropland, and 2 percent is used for miscellaneous purposes. Small grains and hay crops for livestock are the main crops. Peach and apple orchards are important locally. Pastures are mostly of tame grasses and legumes but native grasses grow on the prairie outliers in the west.

Elevation and topography: Elevation ranges from 200 m on the lowest valley floors to 800 m on the highest ridge crests. Ridgetops of these deeply dissected sandstone and shale plateaus are narrow and rolling. Valleys are narrow and steep sided and have steep gradients. Local relief is in tens of meters.

Climate: Average annual precipitation - 1,150 to 1,325 mm. Maximum precipitation is in spring and in fall, and the minimum is in midsummer. Average annual temperature - 14 to 17 C. Average freeze-free period - 180 to 205 days.

Water: The moderately high precipitation is adequate for crops and pastures. Shallow wells are the principal source of water for domestic use. Small ponds on individual farms provide water for livestock, and springs are numerous on the mountainsides and in the valleys. Deep wells are needed for moderate to large quantities of ground water. Large reservoirs on a few of the major streams are sources of municipal water and also provide flood control and recreation.

Soils: The major soils are Udults. They are stony and nonstony and medium textured. These soils have a thermic temperature regime, an udic moisture regime, and siliceous or mixed mineralogy. Well drained, shallow and moderately deep Hapludults (Mountainburg and Linker series) are on ridgetops, benches, and upper slopes. Well drained, deep Paleudults (Nella series) and Hapludults (Enders series) are on the middle and lower slopes and in concave interledge positions. Udifluvents (Ceda series) and Hapludults (Spadra series) are on stream flood plains, and Fragiudults (Leadvale and Taft series) and Hapludults (Pickwick series) are on terraces in the valleys.

Potential natural vegetation: This area supports hardwood forests. The primary overstory species are red oak, white oak, and hickory. Shortleaf pine and eastern redcedar are important on disturbed sites, on shallow soils, and on south or west slopes. Big bluestem, switchgrass, indiangrass, and little bluestem are important understory species under medium to open forest canopy. Broadleaf uniola, longleaf uniola, wildryes, and low panicums are important species under heavy canopy.

(From "Land Resource Regions and Major Land Resource Areas of the United States". United States Department of Agriculture Soil Conservation Service Handbook 296. Dec. 1981. page 85.)