Nothing in this chapter shall be construed as affecting—
(2)
any requirement under State law that lands, waters, and interests therein may only be acquired for conservation purposes if the owner thereof is a willing seller; and
(3)
the authority of the Secretary of Agriculture under the Act of March 2, 1931 (46 Stat. 1468–1469, 7 U.S.C. 426–426b).[1]