This may not be an option for hikermor in SoCal however, with the meager shrubs they call "trees" down there.
"Meager?!!" You should know that SRI is home to the only stand of Torrey pines (Pinus torreyana) outside San Diego. Some of them tower to heights of at least 25-30 feet (8-10 meters)...
We do have our share of knee high bushes (wanna be trees) which is why I am digging out tall gaiters that I haven't used in years...