The Wish-Tree — John Ciardi

A little boy who's about to turn six years old is thinking about cake and toys and the best birthday gift of all, a puppy. Daddy tells him to look for a Wish-Tree, on the bark of which is engraved TAKECAREOFYOURWISH. The boy falls asleep as he ponders his father's advice, and he dreams of a Wish-Tree, with a trunk as big as a house and so tall that the sky had to bump up to get over the top of it.
A remarkable adventure follows, involving the limitless nature of wishing and responsibility. Written by the noted teacher and poet John Ciardi, this fanciful tale is filled with inventive, dreamlike drawings by Louis S. Glanzman, illustrator of the Pippi Longstocking books.