What is the importance of the Pinery in the novel, Wolves of Eden?

The Pinery is a location outside the walls of Fort Phil Kearny where loggers acquire the lumber for use in the continuing construction of the fort. Some six miles outside the walls, it is the frequent target of raids by the Sioux and therefore the site of much violence and death. Michael and Tom often ride guard for the woodtrain travelling to and from the Pinery and see a great amount of combat against raiders. The Pinery also features a fortified headquarters called the blockhouse where Captain Brown oversees the activity of the logging camp. It is in the blockhouse that Captain Brown hides Tom after Michael's arrest, and Sarah comes to escape with Tom from the location as well.