Musannaf Ibn Abi Shayba 13:2624

Abu Bakr narrated to us, he said: Ibn 'Uyaynah narrated to us, from Yahya ibn Sa'id, from Bashir ibn Yasar, from Sahl ibn Abi Hathma, that the Messenger of Allah (may Allah bless him and grant him peace) forbade the selling of fruit for dates. And he granted a concession regarding the 'ariyya (gift of fruit on a tree) that it be sold by its estimation, so that its people may eat it fresh.