I'm not sure whether this is all Marybird sang. The Abrahams and Foss one is not a songbook. In two of the other versions, the verb is "valley" too. The authors comment (p. 17):

Other changes are more likely to have occurred not unconsciously but from misunderstanding or trouble with words like "tavern" and "valley." When asked about the meaning of the latter, informants demonstrated no common understanding of the word. The responses ranged from statements that it meant "to value" to it meant to "fight" or "whup em".

~Masato