A good article covering the controversy at:
http://www.tamu.edu/ccbn/dewitt/mckshorts4.htm

However, I am more interested in whether Emily West was the actual inspiration for the song rather than another "High Yellow Negro,” and who was the actual author of the song? Black face minstrel shows can be dated at least ten years before the battle of San Jacinto, an art form known to have used African descent contributors as “ghost writers.”
A few e-notes:

1.,“Although no name is given as the song's composer, a hint comes in the fourth line of the chorus which refers the soldier is from Tennessee.
The first copyrighted edition of the song was published in 1858 in New York. The cover states the song was "Composed and Arranged Expressly for Charles H. Brown by J.K. In the nineteenth century ghost" composers were kept secretive, especially if the songs had slave folksong origins.”
http://joynord.com/

2., “The folksong tells of a black soldier who left his sweetheart (a “yellow rose”) and yearns to return to her side although other sources think the song refers to General Santa Anna's mulatto girlfriend, who stole his battle plans before the battle of San Jacinto and delivered them to the American army.”
http://www.joanncastle.com/tracks/y.html

3., “Bunkley's novelistic representation of the events provide motive, emotion, sentiment, and introspection to flesh out the bare bones of the presented history. According to Bunkley, a twenty year old orphaned Emily D. West journeyed to Texas in the hope that its status as Mexican territory would help her to realize more freedom than she had experienced in the so called free environment of New York. Upon arriving in Texas, West discovered that her freedoms were minimal, that the land was much more harsh than she had anticipated, and that her circumstances were not appreciably different from those of enslaved African-Americans. She fell in love with a black man, a musician, thought to be a runaway from slavery. Bounty hunters and the pressures of the fast-approaching war for independence from Mexico interrupted their sustaining relationship. Her lover attempted to get away from his pursuers and the war, while West found herself in the midst of both; their separation led to his composing "The Yellow Rose of Texas."“
http://www.blackpast.org/?q=perspectives/yellow-rose-texas-ironic-origins-state-song
4., “Turner also joined others in championing the notion that Emily was the scrumptious mulatto celebrated in the 19th-century song "The Yellow Rose of Texas."
That is disputed by Texas folklorist Francis E. Abernethy, who participated with Lutzweiler on Saturday in the Texas history conference.
"Even in the realm of Texas legends, one has to draw a line somewhere," says Abernethy, an English professor at Stephen F. Austin State University and executive secretary and editor for the Texas Folklore Society.
"There is absolutely no way anybody can tie this art song to Emily West," he advises. Although its tune possibly came from some folk tune, "it's not a folk song."
Abernethy says it was written as a minstrel song by someone never identified except by the initials J.K. and copyrighted in 1858 for Charles H. Brown of Jackson, Tenn., a bookman and publisher.”
http://www.texnews.com/texas97/yellow031297.html

Thank you for your input.
Allen L. Lee