In order to reduce the need for public expenditures in the acquisition
of lands which may be brought into public ownership through the enforcement of appropriate tax delinquency laws, and, by bringing about the handling of such lands upon a sound social and economic basis, to terminate a system of indeterminate and unsound ownership injurious to the private and public interest alike, no additional lands shall be acquired within any State
by the United States
under sections 567a
of this title after June 30, 1942
, unless the State concerned has prior thereto provided by law for the reversion of title to the State or a political unit thereof of tax-delinquent lands and for blocking into State or other public forests the areas which are more suitable for public than private ownership, and which in the public interest should be devoted primarily to the production of timber crops and/or the maintenance of forests for watershed protection, and for the enforcement of such law: Provided, That in the administration of sections 567a
of this title prior to June 30, 1942
, preference will be given to States applying for cooperation hereunder which provided by law for such reversion of title under tax delinquency laws.