The McCaslin-Edmonds property is "seventeen miles" from Jefferson. This location includes the road that connects the two, and the "gate" at the place where one turns off the road to head to the plantation.
Cotton is the principal crop raised on the Edmonds' place, and the route of the narrative in "The Fire and the Hearth" goes through two of the fields in which it is grown. Edmonds notes that his tenants are "laid-by" at this time of year, which means they have already planted the cotton (231).
The Edmonds family descends from Lucius (Old Carothers) McCaslin "by the distaff" - that is, from McCaslin's daughter rather than one of his sons (5). The first Edmonds in this line may have been the man who married that daughter, or could just as easily be the man who married the daughter of that daughter - the novel provides no information about the sequence. The novel does say that Cass Edmonds, the grandson of Lucius McCaslin's daughter, "bears his father's name," that is, Edmonds (9, 43) - but whether that was also the name of Cass' grandfather cannot be determined.
