Not too surprising with the extent of deforestation. Grassy slopes heat up much more than forest, making the fog evaporate faster and travel less far inland. Reversible if they get the coastal belt replanted, but that's a big 'if'.
Some scientists farther north are gathering data about growth the last several decades, and back to like the 1600s. Rather interesting what they are learning. They are also giving a presentation in Eugene, Oregon, the coming March 13th, 2010. The Mount Pisgah Arboretum announces the Tallest Trees presentation: http://mountpisgaharboretum.org And it also links to a site where people can get tickets in advance. Researchers Van Pelt & Sillett will be the presenters. ~ ~