Lovely Joan is a traditional English folk song (Roud #592), and the tune to which it is sung. Its melody is most familiar to modern audiences as the counterpoint tune used in British composer Ralph Greaves's arrangement of Fantasia on "Greensleeves" from Ralph Vaughan Williams's opera Sir John in Love.
The words to "Lovely Joan," as printed in The Penguin Book of English Folk Songs, are as follows:
Sung by C. Jay, Acle, Norfolk (R.V.W. 1908).
The melody for Lovely Joan was used by Emerson, Lake & Powell on the track Touch and Go of their eponymous album Emerson Lake & Powell in 1986 (uncredited).