And in _The Lord of the Rings_ - Tom Bombadil
rescues the hobbits from one.
Actual carnivorous plants settle for insects,
I think. There's an argument, though, that dead
animals at the foot of a tree are good fertilization.
I don't remember that the Krugg in Angus McAllister's
_The Krugg Syndrome_, alien trees conquering humans
by telepathy, are meat eaters. They do have animal
servants, and as I noted, blood and bone are good
for plants.
In Diane Duane's Star Trek original novel
_Doctor's Orders_ (1990), the commander of the
Enterprise - Dr McCoy, put there after sassing Kirk -
wants to discourage Klingons from raiding the
otherwise-developed planet while Kirk is on it,
so he says some Enterprise crew were eaten by
the trees which don't or perhaps do appreciate visitors.