Isn't that what those swimming-pool-noodle-looking-things in cow pastures are for? The cows walk under them and the insecticide in the noodle keeps the grubs off their backs...?
We call them wolf worms around here. You have to cut off the air by applying a creme or oil of somesort and when it comes up for air, tweeze it out. It probably will take several tries. Then disinfect the wound. Keep it cleaned as it can get infected easily. Neosporin will work on it.
Read the entire post checking locations....I don't think of myself as a spring chicken but have neve had to deal with this perticular infestation. I am thinking there is finally a good reason to live in California.