wouldn't you say tall tree?

It is very common in (American) English to say "cut down" or "chopped down" when referring to trees. I think He cut down a tall tree should be accepted.* Reported.

The English translation is unnatural (reported 6 July 2018). Did he chop the tree down or just prune it? Is this obvious in Swahili or would you need some context?

Why not "a tall tree"--marked wrong.

I thought that the whole idea of an object infix was to emphasize the particularity of the the tree - thus "...the tall tree".