Abu Dawud
The Rites of Hajj
Book Number: 004 / Hadith Number: 2030
Narated By Ali ibn AbuTalib : The Prophet (pbuh) said: Its (Medina's) fresh grass is not to be cut, its game is not to be driven away, and things dropped in it are to be picked up by one who publicly announces it, and it is not permissible for any man to carry weapons in it for fighting, and it is not advisable that its trees are cut except what a man cuts for the fodder of his camel.