District of Columbia. Public buildings and grounds, hearings, 74th Congress, 1st session, on H. Res. 221, directing Secretary of Interior to transmit to House of Representatives statement of director of National Park Service concerning destruction of trees in proposed Union Square project and in the Mall, H. Res. 222, directing Secretary of Interior to transmit to House of Representatives statement of director of National Park Service concerning destruction of trees in proposed Union Square project and in the Mall, May 28, 29, 1935.