Explore the findings from the projects we’ve funded through our Research Grants Program.
Recent League-funded research by Richard Dodd, an Environmental Science Professor at the University of California, Berkeley, confirms that northern groves (north of the Kings River drainage) have lower genetic diversity than central and southern groves. This could have profound consequences for long-term conservation strategies for the species, especially considering the changing global climate. Learn more about this research.
Genetic profiles of specific coast redwood strains mean some trees could demonstrate greater resilience in certain types of climatic conditions than others. Learn more about this research.
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. Learn more about this research.
Though common in chaparral, manzanitas can also eke out a living on the edges of coast redwood forests. A recent study funded by Save the Redwoods League explored the differences between coastal versions of this sturdy red-barked shrub and their more sun-loving cousins. Learn more about this research.
Giant sequoias can live for thousands of years, but they sometimes have difficulty getting started. Unlike coast redwoods, giant sequoias rarely sprout from their bases. Their reproductive future lies in their tiny (0.2-inch-long) seeds, which need just the right combination of soil, sun and moisture to survive. Learn more about this research.
More than 30 years ago, giant sequoia seeds were collected in 23 groves representing the species’ range from north to south in the Sierra Nevada. They were propagated and planted on US Forest Service land 20 miles east of Auburn, California, that was hotter, drier, lower in elevation and farther north than any of their original homes. This experiment, the legacy of William J. Libby, UC Berkeley emeritus professor and Save the Redwoods League board member, has been studied and carefully maintained ever since. Learn more about this research.
In the past 70 to 80 years, most fires in California’s coast redwood forests were prevented or suppressed. But in 2008, more than 2,000 fires ignited forests in Northern and Central California during a single summertime lightning storm. Overwhelmed by conflagrations in drier areas, firefighters allowed many of fires in coast redwood forests to burn. Learn more about this research.
Tanoak (Notholithocarpus densiflorus) grows in coastal forests in Oregon and California. Compared with the majestic redwood, it’s scruffy and small. But this humble hardwood plays an important ecological role in the redwood forest ecosystem. Its medium-height trees add a second canopy to the complex architecture of an old-growth redwood forest, creating more niches for diverse species. And its nutritious acorns feed bear, deer, rodents and birds. Learn more about this research.
Researchers found in a 2007 study that coast redwoods’ genetic diversity was “very high” throughout the state, and more divergent in Central California. These Central California redwoods are most threatened by climate change and “should be a conservation priority,” said Richard S. Dodd, a professor of plant population genetics at the University of California, Berkeley. Learn more about this research.
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.” Learn more about this research.
Genome science has made stunning advances in the past few decades. But until recently, no one had tried to sequence Sequoia sempervirens, the coast redwood. Part of the problem was the species’ complexity. Humans are “diploid,” meaning that for each chromosome, they have one copy inherited from their mother and one from their father. Redwoods, on the other hand, are “hexaploid,” meaning that they have three copies from each side, which triples the size of their genome. Learn more about this research.
In 2006, Save the Redwoods League recruited eight scientists to survey scientific literature about how coast redwood forests respond to “disturbance events” such as fires, windstorms and floods. The scientists considered how redwoods fit into two broad categories of trees: those that need major disturbances to perpetuate themselves and those that don’t. The seedlings of disturbance-dependent trees germinate in open spaces, grow quickly to outcompete other vegetation and tend to form even-age stands. Species that don’t need disturbances tend to be shade tolerant, slower growing and longer lived. They usually grow in uneven-age stands. Learn more about this research.
In 1923 Emanuel Fritz, then a Professor of Forestry at UC Berkeley, and Woodbridge Metcalf secured for study a one-acre grove of second growth trees along the Big River in Mendocino County. By that year, much of California’s old-growth redwood had been logged and a second generation of trees had begun to grow. Fritz and Metcalf intended to study tree growth on their plot in order to better understand just how a second growth forest develops. Learn more about this research.
Grassy fuels on the forest floor were not the cause of frequent prehistoric fires in giant sequoia (Sequoiadendron giganteum) groves, according to UC Berkeley researchers and California State Park ecologists. Learn more about this research.
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. Learn more about this research.
In the upper reaches of their crowns, coast redwoods struggle to lift water and nutrients into their leaves. This struggle begins a process that limits tree growth, according to a team of researchers studying redwoods in Prairie Creek and Humboldt Redwoods State Parks. Learn more about this research.
Finding scientific resources on a specific plant species like the giant sequoia can be a daunting task. From the tangled network of information on the World Wide Web, the Giant Sequoia Ecology Cooperative Web site provides quick resources, ranging from maps and informational documents to expert contacts, which link the world to data on this rare tree, found only along the western slopes of the Sierra Nevada. Learn more about this research.
Giant sequoias are sometimes simply referred to as “big trees” and with good reason: They are the largest trees by volume and among the largest living things on Earth. These massive trees do not function in a void; they are supported by an intricate network of natural processes that keep the ecosystem working properly. Learn more about this research.
Dr. Raj Ahuja and Dr. David Neale have taken a big stride in coming closer to knowing the origin of polyploidy in coast redwood. Learn more about this research.
William Ellyson and Stephen Sillett found evidence that demonstrates that epiphytes—plants that use other plants for mechanical support—play a crucial role in maintaining the biodiversity of redwood forest canopies. It’s well known that these hangers-on thrive in the old-growth Douglas-fir forests of Oregon and Washington, in places amassing the weight of two concert grand pianos per acre. Ellyson and Sillett reveal in this study that Douglas-fir has a rival in Sitka spruce, a tree that grows in and among northern coast redwood forests and supports a shockingly high diversity of epiphytes. Learn more about this research.
Coast redwoods have captivated scientists since their discovery, and thousands of articles, dissertations, and books have been written in an attempt to decipher various aspects of these magnificent trees. Finding all of this information was considerably more challenging until Deborah Rogers, a research geneticist and conservation biologist with the Genetic Resources Conservation Program at the University of California, Davis, stepped in to organize a bibliography of scientific materials written about coast redwoods in the past 50 years. Learn more.
For many years, selective thinning has been considered a potential tool for accelerating old-growth forest characteristics in the dense stands of young trees that typically cover harvested redwood lands. Now, research by the US Forest Service has confirmed the wisdom of thinning, or removing select trees to reduce competition in a stand. Learn more about this research.
The League funded an ambitious study to learn more about white-footed voles. Unfortunately, they’re almost impossible to find in the luxuriant understory of the typical coastal redwood forest. In response, researchers have released the hounds. Learn more about this research.
Martens are agile, 2-foot-long members of the weasel family. They need ancient forests—and used to thrive in the coast redwoods of California. Today the Humboldt marten, the coastal subspecies of the Pacific marten in California, has vanished from more than 95 percent of its former range. A single population of about 100 remains on the coastal edge of the Six Rivers National Forest, roughly between Crescent City and Arcata. Learn more about this research.
Humboldt State University fisheries biologist Darren Ward was concerned, but not surprised, when New Zealand mud snails showed up in Redwood National Park in 2009. With help from a grant from Save the Redwoods League, Ward and a colleague at the US Geological Survey, Adam Sepulveda, began searching to see if they were moving upstream. Learn more about this research.
A US Forest Service ecologist, Weller decided to check out his own backyard: the redwood forests of Northwest California. He not only found bat activity in winter, but also important clues about the bats’ migrations. When Weller had surveyed a common species called the silver-haired bat in summer, he’d found almost all males. In the winter, however, he began to catch females right away. So he asked Save the Redwoods League to fund research to figure out what was going on. Learn more about this research.
Funded by a grant from Save the Redwoods League, entomologist Peter H. Kerr recently found two new species of fungus gnats near the base of some of the park’s giant sequoias. Learn more about this research.
The range of the black salamander (Aneides flavipunctatus) almost perfectly overlaps with the historic range of redwoods along the Central and Northern California coast. While most animals live on the Earth’s surface, this well-hidden amphibian travels mostly up and down in the rocks and soil. Its vertical approach to life comes in handy when the weather is hot or dry: the salamander moves deeper into the Earth until conditions are more to its liking. Learn more about this research.
Virtually all redwood forests have (or once had) streams in which salmon run and spawn. But after 150 years of damming, water diversion, logging and development, most of these fish species face extinction. Learn more about this research.
Coast redwoods need healthy soil and its tiny organisms to survive. So how will climate change affect the forests’ fungi and bacteria? A research team led by Professor Mary Firestone at the University of California, Berkeley, recently found a way to mimic what the future may hold. Learn more about this research.
In a forest of towering redwoods, the small creatures scurrying underfoot and splashing into streambeds sometimes go unnoticed as visitors crane their necks toward distant treetops. We should look down, though, say researchers from the Redwood Sciences Laboratory, who visited several state parks to study the ecosystems that surround and support those mighty trees. Researchers Garth Hodgson and Hartwell Welsh pay particular attention to tiny amphibians such as frogs, salamanders, newts in redwood forests, because published studies suggest they are indicators of forest health. Learn more about this research.
The coho salmon population in Del Norte County’s Mill Creek depends heavily on the quantity and quality of winter habitat for survival, according to a study by The Rowdy Creek Fish Hatchery and a team of fisheries biologists. Learn more about this research.
Traditionally we think of forest conservation as protection of large areas of land. Is it possible, though, that just one tree could benefit an ecosystem enough to warrant individual protection? Mary Jo Mazurek and William Zielinski report evidence that suggests legacy old-growth redwoods can do just that. Learn more about this research.
Legacy trees, old-growth trees left standing in second-growth redwood forests, could serve as a habitat refuge for terrestrial microarthropods, miniscule bugs that live in the forest floor and maintain healthy soils, not to be confused with the bigger arthropods like spiders and bees. Dr. Michael Camann, Karen Lamoncha and Laura Hagenhauer have found substantially more and a wider variety of the soil bugs underneath these so-called legacy trees than beneath surrounding second-growth trees. Learn more about this research.
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.
From time to time, a resident in Humboldt County will submit a report claiming to have spotted a Pacific fisher or a Humboldt marten. Because Pacific fishers are rare, and because the Humboldt marten was previously thought to be extinct due to human influences such as trapping and logging in their old-growth conifer habitat, these animals remain barely documented. The Corridor from the Redwoods to the Sea, built as a passageway for wild creatures, appears to be prime location to spot small carnivores such as fishers and martens, but despite local accounts, the rare sightings remain unverified by scientists. Where have these small predators gone? Learn more about this research.
It’s likely that Pacific fisher (Martes pennanti pacifica) populations are well distributed in Northern California’s Redwood National and State Parks (RNSP) for the same reason that Humboldt martens (Martes americana humboldtensis) have disappeared, according to research done by Keith Slauson, William Zielinski, and Gregory Holm. Second-growth forest habitats that cover a majority of the park are fishers’ sweet and martens’ sour. Learn more about this research.
Wandering Salamanders (Aneides vagrans), in addition to dwelling on the ground, have been found in high-up patches of humus moss mats in trunk crotches, on limbs, under bark, and in the cracked and rotting wood of coast redwood trees. They may inhabit forest canopies, the researchers of this study speculate, because of a more profitable food resource available there. Learn more about this research.
Based on their research in Pairie Creek Redwoods State Park, Anthony Ambrose and Stephen Sillett have found that mats of humus soil deposited as high up as 265 feet in the crowns of coast redwood trees moderate the climate around them. This makes the mats habitable to a wide variety of insects and animals more commonly found on the forest floor. Learn more about this research.