Nothing in sections 57, 58, and 60 to 65 of this title shall be construed as repealing or in any way modifying the authority granted the Secretary of the Interior by said section 3 of the said Act approved August 25, 1916,¹ to sell or dispose of timber in national parks in those cases where, in his judgment, the cutting of such timber is required in order to control the attacks of insects or diseases or otherwise conserve the scenery of the natural or historic objects in such parks and to provide for the destruction of such animals and such palnt ² life as may be detrimental to the use of any of said parks, or the authority granted to said Secretary by sections 51 to 54 of this title.