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7 U.S. Code § 2266a - Century Farms program

The Secretary shall establish a program under which the Secretary recognizes any farm that—
a State department of agriculture or similar statewide agricultural organization recognizes as a Century Farm; or
is defined as a farm or ranch under section 4284.902 of title 7, Code of Federal Regulations (as in effect on December 20, 2018);
has been in continuous operation for at least 100 years; and
has been owned by the same family for at least 100 consecutive years, as verified through deeds, wills, abstracts, tax statements, or other similar legal documents considered appropriate by the Secretary.
Statutory Notes and Related Subsidiaries
Definition of “Secretary”

“Secretary” means the Secretary of Agriculture, see section 2 of Pub. L. 115–334, set out as a note under section 9001 of this title.