Prolonged drought starting to take its toll on coastal oaks

Oct 1, 2015

Continuing research out of UC Santa Barbara shows our coastal oaks are starting to show signs of stress related to the ongoing drought and record heat.

A coast live oak (Quercus agrifolia) shows signs of severe stress after three years of punishing drought and extreme temperatures.
Credit Jim Logan

The trees are known to be some of the toughest drought-tolerant plants around, but even they are beginning to feel the pressure.

Frank Davis is the director of UCSB's National Center for Ecological Analysis and Synthesis (NSEAS). He said the fact that these trees are suffering—given their evolutionary history—highlights the scale of this drought.

However, Davis said it's not too late for recovery should we have a strong El Niño winter.

"These oaks are surprisingly resilient," said Davis. "They can die way back, drop a lot of leaves, lose a lot of branches and still recover once they've been re-watered adequately."

Davis said the recovery processes can take a while, possibly several years. He said the record heat associated with this dry spell is complicating the drought stress being experienced by these trees.