It is narrated from Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) that the Messenger of Allah (peace and blessings be upon him) gave the Jews of Khaybar the date palms of Khaybar and its land as well, on the basis that "they would work them with their own resources, and the Messenger of Allah (peace and blessings be upon him) would have half of their fruit."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب المساقاة / 11632