Andy the zones you are referring to are only for grey squirrels. You can hunt the brown ground squirrels all year with no limit.So anywhere near you where it is legal to hunt you can hunt ground squirrels and jack rabbits as much as you like.hope this helps
(start mini-rant)The tree squirrels are literally a plague on the areas, having had a massive population explosion in the last few years. So much so that some are being found recently with rodent plague. The laws say you can't hunt them, though, because of some idiot decades ago deciding that they were endangered or something. This always happens, and with the liberal idiocy that generally infects California, you can't do anything about any sort of pest at all, or hunt virtually anything any more, even in the forest areas.