Frost line depth in Izard County, AR
How deep the ground freezes in Izard County, AR
15 in. Dig to 16 in, just below the frost. Nearest NOAA station: Calico Rock 2 Wsw, 14 mi.
Your building department sets the legal frost line depth (IRC Table R301.2(1)); footings must go below it (R403.1.4.1). Call them before you dig.