In his headnote on "Pretty Little Pink", Leonard Roberts refers to Vance Randoph's OZARK FOLK SONGS, no 756. I haven't had a chance to look that one up yet. He also references Carl Sandburg's AMERICAN SONGBAG, p. 166, and some versions in the Frank Brown Collection of NORTH CAROLINA FOLKLORE, III, no. 78. The texts in the Brown Collection are under the title of "Coffee Grows on a White Oak Tree". Out of the nine versions mentioned by Brown, three refer to "little Pink", but don't seem to have anything else in common with the Kentucky version. The Sandburg version is similar to those in Brown, and he thinks that it goes back to at least the Mexican War as a marching song. The tunes published by Brown and Sandburg, as near as I can tell, don't seem similar to either Leonard Roberts' Kentucky version or to the North Carolina "Black is the Color" traditions.

Other than the reference to "little Pink", I don't see any connection between Leonard Roberts' Kentucky version and this other tradition of "Coffee Grows on White Oak Trees". I am also aware that there are other "Pretty Little Pink" songs. I don't think that they are directly related either.

There does seem to be a relationship between Leonard Roberts' Kentucky version and the one sung by Dellie Norton from Madison County, North Carolina, which is printed earlier in this thread. She has as her first verse the following:

My pretty little pink, so fare you well.
You've slighted me, but I wish you well.
If never on earth I no more see,
I can't slight you like you've slighted me.

She also has the verse:

The winter have broke and the leaves are green.
The time has passed that we have seen.
But I hope the time will shortly come,
Never you and I will be as one.

These are very similar to verses in the Kentucky version. Mike Yates recorded the Dellie Norton version on August 28, 1980. Leonard Roberts recorded Doris Breeding's version in 1957. While there are definite relationships with some of the verses, the two tunes don't seem to me to be similar at all. Dellie Norton uses a variation of the Lizzie Roberts' version of "Black is the Color".

Some of the verses in the Kentucky version also seem similar to those collected by Mellinger Henry in Tennessee. It seems to me like a number of songs have gotten mixed up here and have on occasion been reworked with other materials. It is still not clear to me that anyone has turned up anything that is directly parallel to the version that Cecil Sharp collected from Lizzie Roberts in 1916 in Hot Springs, NC. The Kentucky version from Doris Breeding was "learned from her mother". That would mean that it could easily go back into the 19th century, except we don't know when her mother learned it.

We have a number of tantalizing relationships and definitely a number of missing links in the transmission of this song, and as near as I can tell, nothing that we know for sure pre-dating Lizzie Roberts' version.