This is a hybrid letter box. Or is it supposed to be a letter box hybrid? I don't know. I've placed so many caches recently I can't really keep them straight.
Follow the red until you get to the Christmas color intersection. There, look south by east (168.75 degrees on your compass) 120 feet and you will see two shattered stumps. Go to the first one to find the hybrid letter box.
Welcome to the Rutgers University Ecological Preserve and the Aggressively Literal Cache series. You can find a map of the preserve here.
Hunting occurs in the Preserve September through February. If you are completing the series in those months, please wear appropriately colored clothing and stay on the trails. For your safety, none of these hides are more than a few feet from the trail if they are in a hunting area. If you find yourself going too far off the trail or going past a sign that says you're entering a hunting area, you're going way too far and need to turn around.
To obtain the final coordinates to the mystery bonus cache, assume N 40 30.ABC, W 074 26.DEF. Each cache in the series contains a clue in the logbook to obtain the coordinates to the mystery bonus cache.
If you're completing this series, the parking coordinates will take you to the best place to start. From there, be prepared for a 2.5 mile hike around parts of the preserve from start to finish. Parking is also available in Johnson Park, although that will increase your distance hiked.
For the shortest route to complete the series, here is the best order to complete them:
GC9DGZX, "Hybrid letter box"
GC9DGVW, "Bison on something green and brown in the woods"
GC9DGY0, "Bison hanging from a tree"
GC9DYGN, "Ammo can in the woods"
GC9DH4X, "Friends, Romans, Countrybears"
GC9DGWR, "Lock n Lock in the woods"
GC9DH18, "Field Puzzle"