Identification of important farmlands.

CFR · 2024-01-01 · US · Title 7

(a) (2) (i) The soils have: (A) Aquic, udic, ustic, or xeric moisture regimes and sufficient available water capacity within a depth of 40 inches (1 meter), or in the root zone (root zone is the part of the soil that is penetrated or can be penetrated by (B) Xeric or ustic moisture regimes in which the available water capacity is limited, but the area has a developed irrigation water supply that is dependable (a dependable water supply is one in which enough water is available for irrigation in 8 out of 10 years for the crops commonly grown) and of adequate quality; or, (C) Aridic or torric moisture regimes and the area has a developed irrigation water supply that is dependable and of adequate quality; and, (ii) The soils have a temperature regime that is frigid, mesic, thermic, or hyperthermic (pergelic and cryic regimes are excluded). These are soils that, at a depth of 20 inches (50 cm), have a mean annual temperature higher than 32 °F (0 °C). In addition, the mean summer temperature at this depth in soils with an O horizon is higher than 47 °F (8 °C); in soils that have no O horizon, the mean summer temperature is higher than 59 °F (15 °C); and, (iii) The soils have a pH between 4.5 and 8.4 in all horizons within a depth of 40 inches (1 meter) or in the root zone if the root zone is less than 40 inches deep; and, (iv) The soils either have no water table or have a water table that is maintained at a sufficient depth during the cropping season to allow cultivated crops com

official document · source cfr-2024 · id 7:§ 657.5