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.  

مَا رَأَيْتُ رَسُولَ اللَّهِ ﷺ يُصَلِّي إِلَى عُودٍ وَلاَ عَمُودٍ وَلاَ شَجَرَةٍ إِلاَّ جَعَلَهُ عَلَى حَاجِبِهِ الأَيْمَنِ أَوِ الأَيْسَرِ وَلاَ يَصْمُدُ لَهُ صَمْدًا