Tree and Leaf

Tree and Leaf is a small anthology of works by J. R. R. Tolkien published in 1964 and originally illustrated by Pauline Baynes which consisted of:

a revised version of an essay called "On Fairy-Stories"
an allegorical short story called "Leaf by Niggle".

Both pieces were re-issued in the collection The Tolkien Reader, and have also appeared in various subsequent collections.
Tolkien's poem "Mythopoeia" was added to the 1988 second edition, and his poem "The Homecoming of Beorhtnoth Beorhthelm's Son" was added in the 2001 third edition.