The ghouls at the Slog have successfully cultivated tarberries in a former swimming pool, and have established the location as a trading post centered around the crop.Wiseman, the leader of the Slog tells the Sole Survivor that they are free to take a look around the settlement, and if they are willing, help Holly gather tarberries. If the settlement comes under attack by super mutants, Wiseman will ask for help, explaining that they need help removing this threat, as they can't sell tarberries without traders, and the trade caravans need safe roads in order to reach the Slog.
Three south in a pond adjacent to a three-way junction southwest of the Slog.
Four located on the northeastern shore of Dark Hollow Pond, two of the four are against rocks.
Eight located in a large pond northwest of MS Azalea.
The player character is not required to have the Slog as a settlement to harvest the berries, but the settlers must be alive. Additionally if one does control the settlement, settlers must be assigned to farm them.
↑Wiseman: "Sure, there are prettier farms in the Commonwealth, but none of them know how to grow tarberries like we do." (Wiseman's dialogue)
↑Sole Survivor: "I think it's a great idea." Wiseman: "Yeah? Thanks for saying so. Why don't you take a look around? Deirdre's always looking to trade supplies for caps, and Holly could use a hand gathering tarberries." (Wiseman's dialogue)
↑Wiseman: "We can't sell tarberries without traders, and trade caravans need safe roads. There's a gang of Super Mutants that's been preying on anyone who comes near their turf, including traders. It'd be a great help to us if you could take care of those brutes once and for all." (Wiseman's dialogue)