From what I can find here, it seems Douglas Fir, Frasier Fir, & spruce trees are okay if they're all flying about and decide to perch on the Christmas tree and do the inevitable nibbling.

Obviously I want to keep them OFF the tree, because of the lighting wires and ornaments, but just checking that it won't hurt them.

The biggest thing about x-mas trees is to make sure they are not treated with pesticides and other things that is what is most important. I personally would keep them off that is my opinion unless you chopped it down yourself. This is what I have read in my bird magazine this month. I will check and see if they talk about which ones are safe if they are not treated.

Thanks Elly definitely something to ask about. The only answer I might trust though is from the local grower down the road.

Also I read that sap is not bad but it can be sticky on their legs. I will have to read my bird mag that I got this month for more information okay.