The grove was in the middle of the forest. For some reason the entire forest was just called the Kakusa grove. As Falk said, it was because the grove was the main feature and divided the forest into its respective territories. To the east was the Tokage. To the west was the grenwald clan. If Cannon just continued to make his way to the grove, he just had to make a turn and he'd be on his way. That being said, the forest brought an edge of insecurity on him.