Sahih Muslim Book 10, Hadith Number 3765.

Jabir (Allah be pleased with him) reported that Allah’s Apostle (may peace be upon him) visited Umm Mubashshir al-Ansariya at her orchard of date-palms and said to her: Who has planted these trees of dates-a Muslim or a non-Muslim? She said: A Muslim, of course, whereupon he said: Never a Muslim plants, or cultivates a land, and it out of that men eat, or the animals eat, or anything else eats, but that becomes charity on his (planter’s) behalf.