Brown, North Carolina Folklore, vol. 5, "The Music of the Folk Songs," has five different melodies for five different versions of "One Morning In May."

An unusual version (1915) was collected by Owen Wister (author of The Virginian" and "Lin McLean") or possibly composed by Wister. The version (E, p. 14-15) attached to Wister, however, is one of five of this type. "The structures of all five versions are identical, and melodically (excepting the Owen Wister version), the second and last measures are identical in all." Multiple versions suggest that Wister collected the song.

Lyr. Add: ONE MORNING IN MAY (Wister?)

Good morrow, good morrow, good morrow, said she.
And where are you going, fair lady?, said he.
I am going to the bank, to the bank of Lolee
For to see the water gliding, hear the nightingales sing.
For to see the water gliding, hear the nightingales sing.

Unfortunately, I don't have vol. 3 so I can't set down the remaining verses. If anyone has them, I would greatly appreciate seeing them posted.
"Scale: Hexachordial. Tonal center: c. Structure: abb1a1a2 (2.2.2.2.2) (numbers superscript) = abb1a1 (2.2.2.4)."
Another thread (4319): Morning in May