2 U.S. Code § 2186
2 U.S. Code § 2181 is about Square 580 landscape maintenance. It is under Subchapter VIII (Miscellaneous) of Chapter 30 (Operation and Maintenance of Capitol Complex) of Title 2 (The Congress) of the Code.
For fiscal year 2016 and each fiscal year thereafter, the Architect of the Capitol, in consultation with the District of Columbia, is authorized to maintain and improve the landscape features, excluding streets, in Square 580 up to the beginning of I–395.