Section, added Pub. L. 87–834, § 21(a), Oct. 16, 1962, 76 Stat. 1063; amended Pub. L. 94–455, title XIX, § 1906(b)(13)(A), Oct. 4, 1976, 90 Stat. 1834, authorized deduction of expenditures by farmers for clearing land.

Pub. L. 99–514, title IV, § 402(c), Oct. 22, 1986, 100 Stat. 2221, provided that: “The amendments made by this section [amending sections 263 and 1252 of this title and repealing this section] shall apply to amounts paid or incurred after December 31, 1985, in taxable years ending after such date.”