Sahih Bukhari Volume 004, Book 053, Hadith Number 412.

Narated By Ibn 'Abbas : Allah's Apostle said on the day of the conquest of Mecca, "There is no migration now, but there is Jihad (i.e. holy battle) and good intentions. And when you are called for Jihad, you should come out at once" Allah's Apostle also said, on the day of the conquest of Mecca, "Allah has made this town a sanctuary since the day He created the Heavens and the Earth. So, it is a sanctuary by Allah's Decree till the Day of Resurrection. Fighting in it was not legal for anyone before me, and it was made legal for me only for an hour by daytime. So, it (i.e. Mecca) is a sanctuary by Allah's Decree till the Day of Resurrection. Its thorny bushes should not be cut, and its game should not be chased, its fallen property (i.e. Luqata) should not be picked up except by one who will announce it publicly; and its grass should not be uprooted," On that Al-'Abbas said, "O Allah's Apostle! Except the Idhkhir, because it is used by the goldsmiths and by the people for their houses." On that the Prophet said, "Except the Idhkhir."