Sunan Abi Dawud Book 2, Hadith 302
The Prophet (ﷺ) used to pray facing his camel.
I saw Sharik who led us in the 'Asr prayer during a funeral ceremony. He placed his cap in front of him, that is, for saying the obligatory prayer the time of which had come.
I never saw the Messenger of Allah (ﷺ) praying in front of a stick, a pillar, or a tree, without having it opposite his right or left eyebrow, and not facing it directly.