Quercus agrifolia on the left, Q. wislizeni on the right.
Q. agrifolia - bark is different, acorns are long and skinny compared to Q. agrifolia and they take longer to mature. I also look at the foliage.
Cabrillo College, near the west side of Building 500.
7339 Mesa Dr. as seen in picture at the top.
Wilder State Park, intermixed with Q. agrifolia.
Empire Grade - Crest Farms - not really in the front yard, but if you go during the holiday season you will see the same ones as I.