By Lorena Anderson, UC Merced – UC Merced researchers have evidence that California’s forests are especially vulnerable to multi-year droughts because their health depends on water stored several feet below ground. “Each year our forests, grasslands and shrublands depend on water stored underground to survive the dry summers, but during multi-year dry periods there is not enough precipitation in the wet winter season to replenish that supply,” said Joseph Rungee, UC Merced graduate student and lead author on a new paper published in the journal Hydrological Processes.