A Kite-Eating Tree is a deciduous tree of indeterminate type. According to Charlie Brown, it is impossible to tell a kite-eating tree from non-kite-eating trees by sight until it catches a kite in its branches, which it slowly devours. Charlie Brown often envisioned such a tree with a huge grin on its "face".
Many of the kites that Charlie Brown attempted to fly were eaten by a particular Kite-Eating Tree, which he frequently engaged in one-sided dialogue. Once Lucy van Pelt threw Schroeder's piano into the Kite-Eating Tree, which it also ate, proving that the phenomenon was not simply a product of Charlie Brown's imagination.
Besides being able to eat inedible objects, the Kite-Eating Tree has some other strange characteristics. It is apparently not rooted to the ground, seeing as on one occasion it walked straight up to Charlie Brown's front door, which Charlie Brown says that he hates.
Apparently the Kite-Eating Tree can even distinguish between different "flavors" of kites; in a 1982 strip, Charlie Brown wonders what "flavor" kite he should give the tree this year, and finally settles on lemon, since he took strawberry the year before. On one occasion, the tree visibly shuddered at the notion of Charlie Brown giving up kite-flying.
In a 1995 strip, Linus shows great concern because of the tree's presence, wondering what kind of world he was living in that a Kite-Eating Tree could exist. Later that year, Lucy threatens to throw Linus' blanket into the tree; not long afterwards, she actually did; she did the same with Schroeder's piano, which resulted in a failed rescue attempt by Snoopy's "World Famous Rescue Specialisrt" character (he failed because he couldn't climb trees).
One noteable storyline (which has been said as being more fit for Bloom County than Peanuts) Charlie Brown threatening the Kite-Eating Tree that if it took a bite out of his kite, he would bite it, which he did, thus getting himself in trouble with the Environmental Protection Agency. He ran away to avoid being sent to jail and became the coach of a baseball team of very small children. Later, Linus van Pelt convinced Charlie Brown that it was safe to come home, because the tree had fallen over in a rainstorm; nonetheless, the Kite-Eating Tree, or another of its species, later returned. (This storyline was adaptated into animation in It's an Adventure, Charlie Brown.)
Once, after the tree ate yet another of Charlie Brown's kites, Lucy shouted at it so loudly that it regurgitated not only that kite but also a flood of other people's kites, suggesting that, no matter how many kites the tree holds, it only eats one at a time, saving the rest for future feasts.
Charlie Brown has told Linus that Kite-Eating Trees "eat the paper like it was fried chicken, and spit out the sticks like bones!" Charlie Brown may have, in his frustration, been exaggerating, for no sticks have been seen lying around the Kite-Eating Tree (possible it moves around so it might be in a different place every time it eats).
Evidently kite-eating trees have physiologies somewhat similar to animals, since Charlie Brown once threatened to kick the Kite-Eating Tree right in the "stomach." However, when he kicked its "stomach", Charlie Brown hurt his foot, remarking that Kite-Eating Trees "have hard stomachs."