A more extensive list of the flora on the PCT:Tom Chester.
How to get here:
Drive to the Thule Canyon rd. (Navigation: Anza Thule Canyon rd)
Drive the dirt road for up to 2.1 mile and park at the gate. (Anza Borrego Desert Boundary)
You need some ground clearance to drive this road. On the way back, driving uphill, you may need 4x4.
Not recommended after rain.