This week, our research partners from UC Berkeley braved the fall heatwave to check on how some old redwood forests are handling the drought in the Santa Cruz Mountains. I joined them among the redwood giants at Henry Cowell State Park on Wednesday as they measured drought stress levels in both large and small coast redwood, Douglas fir, and California bay trees.
Swinging from ropes in the canopy, researchers including Anthony Ambrose and Wendy Baxter from the League’s Redwoods and Climate Change Initiative, dropped small sections of leaves and stems to forest floor for analysis. I got to dust off my field techniques and help them analyze how drought stressed the foliage was using an instrument called a pressure chamber.
Early results show that the smallest trees were more drought stressed than the larger trees, likely because they have smaller roots and less access to water belowground. Fortunately, the trees have seen droughts like this one before and prevailed.
I’m confident that the redwoods will pull through these dry days, but we will keep studying how intense weather impacts the redwood forest so that we can do everything we can to protect them as climate changes.
Read San Francisco Chronicle’s coverage of this research here and learn more about our Redwoods and Climate Change Initiative here.
2 Responses to “Drought in the Redwoods Makes Headlines”
Diane Davis
I have five 40 year old redwoods in my backyard. Noticed more yellow leaves this year. Also there has been the development of four homes in the field behind our home. The builders worked very diligently to compact the sandy soil and install drains, i.e. lower the water table during this past rainy year.
To preserve them, I have decided to water them, starting today—-probably need to flood them. How much water and how often should I water them? We have been receiving more fog this summer, but probably smoke from Big Sur Fire mixed in with fog too. How does smoke affect my trees? Does hosing off the branches help the tree?
Any advice would be appreciated. Perhaps you could recommend an arborist. I live in Scotts Valley near Henry Cowell Redwood Redwood Park.
Thank you. Diane Davis
Save the Redwoods League
Thank you so much for the comment and questions. A qualified tree care specialist would the be the best resource for determining what exactly is going on with your redwoods and how to best care for them. You can find a specialist on the Tree Care Industry Association website: https://www.tcia.org/TCIA/Directories/FindQualifiedTreeCare.aspx?ZipCode=95066&State=CA&Accreditation=0