7 C.F.R. § 12.32 : Agriculture — OFFICE OF THE SECRETARY OF AGRICULTURE — HIGHLY ERODIBLE LAND CONSERVATION AND WETLAND CONSERVATION — WETLAND CONSERVATION — Converted wetland identification criteria

(a) Converted wetland shall be identified by determining whether the wetland was altered so as to meet the definition of converted wetland. In making this determination, the following factors are to be considered:
(1) Where hydric soils have been used for production of an agricultural commodity and the effect of the drainage or other altering activity is not clearly discernible, NRCS will compare the site with other sites containing the same hydric soils in a natural condition to determine if the hydric soils can or cannot be used to produce an agricultural commodity under natural conditions. If the soil on the comparison site could not produce an agricultural commodity under natural conditions, the subject wetland will be considered to be converted wetland.
(2) Where woody hydrophytic vegetation has been removed from hydric soils for the purpose of or permitting the production of an agricultural commodity, the area will be considered to be converted wetland.
(b) A wetland shall not be considered to be converted if:
(1) Production of an agricultural commodity on such land is possible as a result of a natural condition, such as drought, and it is determined that the actions of the person producing such agricultural commodity does not permanently alter or destroy natural wetland characteristics. Destruction of herbaceous hydrophytic vegetation (i.e., plants other than woody shrubs or trees) as a result of the production of an agricultural commodity shall not be considered as altering or destroying natural wetland characteristic if such vegetation could return following cessation of the natural condition which made production of the agricultural commodity possible; or
(2) Such land is correctly identified as farmed wetland or farmed-wetland pasture.

7 C.F.R. § 12.32