Our class meets at the entrance road to the water filtration plant, right by the historic union pacific railroad trestle on Stenner road. Take Highland Drive to Mt. Bishop road, turn right, go to end at Poultry Unit, turn right on Stenner Road to trestle. Map on p. 46 of your Field Guide. Go to location 7.
This is a ten minute bike ride from central campus.
Here's student project about the location: http://polyland.calpoly.edu/places/AgLand/studentsites/2006a/index.html
Here's a Google Earth tour: http://polyland.calpoly.edu/places/AgLand/studentsites/2006a/cheda.kmz