Wind and drought-stressed trees a perilous North Coast combination amid string of punishing storms
“You don’t see too many of those,” said Ryan Ferrell, a research scientist at the facility dedicated to ecological study and education.
Scorched by wildfires and strained by historic drought, Pepperwood’s forests are vulnerable, said Devyn Friedfel, the assistant preserve manager.
Drought prompts a tree’s root system — the structure that stabilizes the tree and absorbs water and nutrients — to recede, weakened or dying in some cases, he said.
And changes in the soil itself from fire and drought can make surviving trees even more vulnerable. Many can fall victim to winds in summer and fall, when the soil is dried out and cracks, Friedfel said.
Then add copious amounts of winter rain, as in the past two weeks.
Rain-saturated soil becomes “kind of soupy,” Friedfel said, further destabilizing trees.
Across the North Coast, the storm has claimed many of the region’s two most famous species: coast redwoods, which have a shallow system of interlocking roots that hold up multiple trees, and Douglas firs, which have a deep tap root that allows them to sway in the wind — to a certain point.
Falling trees are “part of the natural cycle,” Friedfel said.
Tosha Comendant, Pepperwood’s conservation science director, said Thursday the storm’s impact hadn’t been fully assessed because the preserve’s old ranch roads have been closed, as usual, for the winter.
On Friday, she and other staffers, on foot and in all-terrain vehicles and bearing chainsaws, planned to survey more of the hilly preserve located northeast of Santa Rosa.
Acknowledging the damage done by the four atmospheric rivers, Comendant also noted a study last year that said the western United States and northern Mexico are experiencing their driest period in at least 1,200 years.
The drawback to a storm series like the current one, she said, is that such copious rain in concentrated periods can’t be captured in saturated soil, despite how thirsty trees and plants might be.”