How do I clean an artificial tree?

A microfiber duster or blow dryer. You might even be able to use canned air, the kind you use to clean keyboards keys.

If it's warm where you are, you might be able to spray it down with a water hose. I use water to clean other faux florals...

I took mine outside and sprayed it with a hose. Then shook it a bit and let it dry before bringing it back inside. Mine is a bamboo style. Worked like a charm.

I have put mine in the shower.....soaking it good and laying it on it's side to drain the water out...then put it upright and let it dry in the shower.

Thank you for your suggestions. As my tree is large, I think spraying it outside would work. The microfiber would be good from my smaller artificial arrangements.

You can spray it with an artificial tree cleaner. https://amzn.to/2tQ5CCc