A lot of people have contemplated that question and more than a few have whittled the number of key destinations down to their list of “100 places to see before you die.”
Mustard comes in a variety of species which hybridize, so there are a lot of different kinds of the plant out there. One of the most common along the coast is Brassica nigra, or black mustard, which grows quite tall and is the stuff you probably see the most of as you (locals) drive up the Gaviota Coast.
A wooden sled sheathed with a metal bottom is the vehicle of choice. At the back end on the bottom, a one-use sheet of plastic is attached, and by leaning back and pulling on the rope attached to the front of the sled, you can reduce your contact point to nothing but this slick surface, achieving speeds of 50 to 60 mph!