Musnad Ahmad 6:15

Bahz and 'Affan narrated to us, they said: Abu 'Awanah narrated to us, from Simak, from Musa ibn Talhah, from his father, who said: The Messenger of Allah (peace and blessings of Allah be upon him) passed by some people at the tops of the palm trees. He said: "What are these people doing?" They said: They are pollinating it; they put the male into the female. He said: "I do not think that will avail anything." They were informed of that, so they abandoned it. Then the Messenger of Allah (peace and blessings of Allah be upon him) was informed, and he said: "If it benefits them, then let them do it, for I only thought a thought, so do not hold me accountable for a thought. But if I tell you something from Allah (Mighty and Majestic is He), then take it, for I would never lie about Allah regarding anything."