Department of Integrative Biology (UC Berkeley)

Researcher Emily Burns noticed that half the ferns in coast redwood forests were evergreen and half were deciduous. Deciduous ferns turn white in the fall while the evergreen ferns stay vibrant green.

Deciduous Ferns May Hold Advantage as Climate Changes

by Save the Redwoods League on

In 2010, funded by Save the Redwoods League and the National Science Foundation, Professor Jarmila Pittermann and Burns began a study comparing the leaves of evergreen and deciduous ferns. Interested in their response to drought, they chose midsummer, just before the deciduous ferns would shed their leaves, in the drier southern part of coast redwoods’ range (in the Santa Cruz Mountains and Big Sur). They expected that evergreen leaves, which are thicker, would show fewer signs of water stress.

Emily Limm found that western sword fern absorbed the most moisture from fog. Photo by Emily Burns

Fog and Redwood Forest Plants

by Save the Redwoods League on

Coast redwood forests depend on fog to survive the nearly rainless summers of California’s Mediterranean climate. It was once thought that redwoods captured this moisture through their roots. But a 2004 Save the Redwoods League-funded study proved that redwoods suck up water through their leaves as well. As a doctoral student at the University of California, Berkeley, Emily Burns set out to discover whether other plants in the redwood ecosystem were equally adept at “foliar uptake.”

Core sampling. Photo by Peter Buranzon

Chemicals in Redwood Rings Indicate Past Water Uptake

by Save the Redwoods League on

It’s no coincidence that redwoods live in the thickest part of “California’s fog belt.” The presence of coastal summer fog has long been regarded a necessary ingredient for the health and perpetuation of coast redwood ecosystems. During drier summer months fog supplies trees with moisture and blocks the evaporating rays of direct sunlight, reducing the amount of water that redwoods lose via transpiration. What’s less understood, however, is exactly how fog frequency has varied in the past century and how redwoods have responded to this variation.

Big brown bat. Photo by Don Pfitzer, USFWS

Bats in Giant Sequoias

by Save the Redwoods League on

Prior to this study, little was known about the bat community in Yosemite’s three giant sequoia groves and virtually nothing was known about how bats use the canopy in any of the Parks’ forests. Dr. Elizabeth Pierson, Dr. William Rainey, and Leslie Chow carried out major research to study bat roosting behavior in fire-scarred hollows at the base of sequoia trees, bat feeding behavior in association with a variety of habitats, and bat activity in the giant sequoia canopy. In addition, they combined observations from this study and others to describe the natural history of Yosemite’s 18 bat species. Learn more about this research.