Soils of Oklahoma

571 soil series mapped on 42.51 million acres

Port, to scale.

Mollisols — soils with a thick, dark, organic-rich topsoil

The state soil, Port, ranks 5th of 571 series here on 649,274 acres. First place goes to Dennis, a Mollisol covering 2.4% of the state’s mapped soil. No order holds a majority; Mollisols lead with 40.1%, ahead of Alfisols at 24.8%.

Atlas series mapped in Oklahoma Guide: state soils and where series began

Soil orders in Oklahoma

Mollisols 40.1%
Alfisols 24.8%
Inceptisols 14.0%
Entisols 9.1%
Ultisols 8.6%
Vertisols 3.1%
Aridisols 0.3%

Largest series in Oklahoma

DennisMollisols · 1,016,629 acres2.39%
StephenvilleAlfisols · 921,654 acres2.17%
CarnasawUltisols · 892,291 acres2.10%
QuinlanInceptisols · 757,334 acres1.78%
PortMollisols · 649,274 acres1.53%
ClebitInceptisols · 621,643 acres1.46%
ClarksvilleUltisols · 601,830 acres1.42%
GrainolaAlfisols · 592,104 acres1.39%
WoodwardInceptisols · 585,046 acres1.38%
KirklandMollisols · 560,021 acres1.32%