I am not so sure about diffusing (to form mist fumes) or burning essential oils? I would possibly double check on that?
We have a mosquitoe problem where I am, and I like to use Citronella candles to keep them away. These candles are basically essential oil. I read that I must not burn Citronella candles anywhere near my birds because of its essential oil content. I am rather safe than sorry and therefore I personally do not burn essential oils in the rooms where my birds are, but maybe I am wrong?
Does anyone perhaps know more on this? ...to reassure us.
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Edited to add...
What I have done is mix some (lavender or rose or lemongrass) essential oils with a bit of lukewarm water in a small spritzer bottle, and then sprayed that immediately and directly onto my bed linen, pillows, curtains, couches and cushions. This leaves them smelling nice without any form of fumes hanging in the air.