Christmas trees

Avoid the breakable ornaments for this year until you see how he does. I would also suggest anchoring the tree to the wall is possible in case he gets curious. I've never had a problem at daycare or at home. Most of the kids didn't get too close because they didn't like the prickles. Often we'll put a few sparkly eye catching ornaments within reach and tell them those are theirs to decorate with and they will stick to those and avoid the rest. Hopefully your little one will keep his feet firmly planted on the floor this Christmas.

Kaden walked last year (he was a year old) and he was really really good with it.

I kept all breakables up high and bought unbreakable ornaments for the bottom of the tree that he could "help" me with.

This year I was able to find little stuffed christmas bears that will go on the tree at and below his level that I'm ok with if he plays with.

I think if you start and explain to them about the tree, allow them to look at/touch in the beginning it wears off pretty fast.

Any ideas how to keep a two year old with ASD away from the tree? I'm dreading putting it up this year, especially since he's a climber.

That's a good question. The sensation of the prickly needles may be enough of a deterant if he is very sensitive to textures etc.
I have two more courses coming up regarding working with children with ASD in the classroom, I will ask and get back to you.

Everything is plastic in our tree. We have cats, so that's when we went plastic. Make sure to attach the tree to the wall.