(a) Authorization of appropriations
Except as provided in subsection (b), there are authorized to be appropriated—

(1) an amount not to exceed 5 percent of the sum of—

(A) the sums received by the Secretary from sales of timber and other products of the forests; and

(B) user fees paid in connection with the use of forest lands; and

(2) such additional sums as may be necessary to carry out the purposes of this subchapter.

(b) Limitation on authorization
Subsection (a) shall not in any way affect payments to the States pursuant to section 500 of title 16.

(c) Spending authority
Any spending authority (as defined in section 651 of title 2) provided in this subchapter shall be effective for any fiscal year only to such extent or in such amounts as are provided in appropriation Acts.