I always enjoy seeing these guys in the wild, doing what they do.
I don't think there is any question as to whether or not boa constrictors are semi arboreal. Though "classed" as a terrestrial species, I've seen more than enough scenes like this that show them in the canopy.
Not just the little ones either.
Check out this short video of a very pretty, wild Suri.
https://www.youtube.com/watch?v=oX2aBfZpUgQ