Redwoods Are Dealing With Climate Change Better Than You Might Expect

By Ezra David Romero

It’s not all doom and gloom at California Gov. Jerry Brown’s Global Climate Action Summit this week in San Francisco. Redwoods are dealing with warming temperatures in a positive way.

Docent Chris Christensen is leading a dozen people about two miles into the Purisima Creek Redwoods Preserve in the Santa Cruz Mountains, an event part of the governor’s summit.  

“It’s very dense redwood forest,” Christensen says hiking next to a creek. “Up higher, it turns more into chaparral.”

For those expecting to hear that redwood forests are doing poorly because of climate change, turns out it’s the opposite.

“We have found that a lot of our old growth redwood forests are actually growing more now than they ever have,” said Deborah Zierten with the Save The Redwoods League. The findings are laid out in the group's State of the Redwoods Conservation Report.

She says even though models suggest the lack of water due to climate change will shrink the suitable habitat for coastal redwoods, there’s no evidence yet they can’t withstand warmer temperatures.

“We like to think of the redwoods as kind of this refuge of stability,” Zierten adds.

The trees are getting more sunlight due to less fog and cloud cover, and that’s good for them. Because of that she says they are adding more wood to the trees than in the past. But the Western sword ferns that grow underneath redwoods don’t grow as well under those conditions.

“We’re interested to see how are these plants going to bounce back,” Zierten says. The group has test plots along the 450-mile long growing region of redwoods. This type of fern is common in redwood forests and quickly responds to changes in rainfall.

Because ferns are an indicator species they could point to how the forest as a whole will grapple with climate change. People can help track the health of ferns in California by joining the groups Fern Watch Project.