Sometimes all you really need out in nature is protection from the flying insects. Breathe easy, eat slowly, and really relax inside a bug-free zone - a screen room tent. Big enough to park chairs and tables inside of; Some can even fit over a standard picnic table found at developed campgrounds.
Contrary to popular belief, California does indeed have a few mosquitoes - mostly near water ways, creeks, rivers, ponds and alpine lakes. Yellow jackets can be equally annoying in summer, usually in the mountains. Little black flies are well known to oak foothills, river valleys and pinyon forests. Big, nasty, biting horse flies are found in hotter areas like the foothills, valleys, and sometimes at the beach.