Sayyiduna Ali bin Abi Talib (may Allah be pleased with him) narrates: The Prophet (peace and blessings be upon him) ordered that skulls (jamajim) be set up in the cultivated fields. (The narrator says:) I asked: What is the reason for this? He said: Because of the evil eye.
Al-Bazzar recorded it; its chain contains a narrator, al-Haytham bin Muhammad bin Hafs, and he is da'if (weak), and a narrator, Ya'qub bin Muhammad al-Zuhri, and he too is da'if (weak).
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الطب / 8433