Idaho Code § 25-2405
The board of county commissioners shall provide as a condition in any order creating a herd district which may hereafter be made that any agricultural lands in the proximity of public domain where cattle, horses, or mules are grazed, shall be enclosed by a lawful fence and that any road extending from agricultural area to such public domain shall contain cattle guards or gates at such places and of such nature as the board shall prescribe. The board of county commissioners may make its herd district orders inapplicable to cattle, horses, or mules straying from such public domain or along roads leading to such public domain until such agricultural lands are enclosed by lawful fence and such cattle guards or gates are installed.
Idaho Code § 25-2405