Sahih Bukhari Volume 7, Book 65, Hadith Number 355.

Narrated By ‘Abdullah bin Umar : While we were sitting with the Prophet a spadix of palm tree was brought to him. The Prophet said, “There is a tree among the trees which is as blessed as a Muslim” I thought that it was the date palm tree and intended to say, “It is the date-palm tree, O Allah’s Apostle!” but I looked behind to see that I was the tenth and youngest of ten men present there, so I kept quiet’ Then the Prophet said, “It is the datepalm tree.”