Rakk Forest is a challenge located in Scylla's Grove that requires players to shoot five rakk nests out of trees. Each step spawns one or more rakk hostile to both players and enemies in the area. They may not attack immediately if sniped from range, and defeating them isn't necessary for the challenge.
Straight north of the entrance from Hunter's Grotto is a small ledge. From the ledge, the tree is visible to the northwest above.
Just east of the first location is a New-U Station, and past the station is a single tree with the nest.
There is a northern circular section with scaylions, and its entrance has a tree to each side of it. The nest is in the western tree.
From the area's southernmost Catch-a-Boat station, there's a tree to the west. It is also visible from the section's northwest entrance, looking south.
The last is in Roothill Village, near Claptrap. It can be seen by backing away from Claptrap to the south and looking to the left of the tall building behind him.