College of Natural Resources, UC Berkeley

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January 11, 2001

UC researchers announce results

10 Jan 2001

By Catherine Zandonella, Media Relations

Berkeley - A common nursery plant may lead to increased complications and possible new management practices in the fight to halt Sudden Oak Death, a highly contagious fungal disease that is killing California oak trees, University of California researchers announced today (Wednesday, Jan. 10).

In a breakthrough in the study of the disease, UC researchers discovered that the rhododendron, a popular ornamental plant, can be infected by the same fungus that is causing the oak disease. The fungus has infected European rhododendrons and, as of yesterday, the researchers confirmed that it also is affecting California rhododendrons, suggesting a transcontinental link. Finding this relatively new fungus in two different parts of the world - and in two species - is unusual, the researchers said.

The rhododendron discovery gives insight to the potential origin and transmission of this pathogen and may suggest new ways of spread. Previously, the pathogen only was known in three other California oaks - tanoaks, coast live oaks and black oaks.

"We now know we have a host that could have carried the fungus a long way," said Matteo Garbelotto, a plant pathologist and adjunct professor in the Department of Environmental Science, Policy & Management in UC Berkeley's College of Natural Resources. "People don't really export oak trees across state lines or around the world," he said, "but they export rhododendrons."

The finding may have a major impact on how scientists manage the disease. Co-investigator David Rizzo, assistant professor of plant pathology at UC Davis, said it may result in new restrictions on the rhododendron nursery industry. "The big concern is that someone will transport a sick rhododendron to a place where there are susceptible oak species," he said.

The breakthrough came when a Clive Brasier, a British researcher who had visited UC Berkeley last summer, later noticed in Europe a fungus that looked like one he'd seen in Garbelotto's lab. The European fungus had been found on rhododendrons in Germany and the Netherlands. Brasier contacted the UC scientists, and researchers from all four countries determined together that the European rhododendron fungus was identical to the California oak-killing agent. This finding established that the fungus is not exclusively found in California and has important implications for international trade.

But Rizzo and Garbelotto needed more proof to confirm the link between the two plant species, and yesterday they got it. Rizzo and Steve Tjosvold, a Santa Cruz County farm advisor, found the fungus in a rhododendron taken from a Santa Cruz County nursery, and Garbelotto confirmed with DNA analysis that it was the same fungus killing the oaks.

The scientists don't know whether the disease was transmitted from California to Europe, or vice versa, or whether it traveled to both places from a third, as yet unknown, location. The fungus, first noted in European rhododendrons in 1993, has not been found in European oaks. However, European scientists are concerned that the disease will spread to European oak forests, particularly those in areas with a climate similar to that of California.

Since the discovery of the mysterious oak-killing illness in California in 1995, researchers have been scrambling to understand the disease and design strategies to stop its spread. It is not known if the fungus recently was introduced into California, or if it is a native fungus that recently became a tree-killer because of environmental changes. Tens of thousands of oak trees have succumbed to the disease, and the researchers have reported up to 80 percent mortality in some infected groves.

Through molecular sleuthing, Rizzo and Garbelotto determined that the disease was caused by a never-before-seen strain of fungi from the genus Phytophthora (Phy-TOFF-thoruh). A relative belonging to this 60-member group caused the Irish potato famine, and another relative is linked to the dieback of cedar trees in Northern California and southern Oregon, eucalyptus trees in Australia and oaks in Mexico, Spain and Portugal.

In California, Sudden Oak Death has been reported from Sonoma Valley in the north to Big Sur in the south, a 190-mile range, as well as east to the Napa County border, about 25 miles inland. The hardest hit counties are Marin and Santa Cruz. The disease affects tanoak (Lithocarpus densiflorus), coast live oak (Quercus agrifolia), and California black oak (Quercus kelloggii) found along the coastal belt in California. To date, the disease has not been found in other oaks such as blue oak or interior live oak.

The dieback is alarming, researchers say, for its potential to disrupt the coastal forest ecosystems. Oaks provide habitat for wildlife and a food supply for small mammals and are frequently planted as ornamentals in gardens and parks. Additionally, downed dead trees create a fire hazard from the resulting buildup of dry fuel.

There are similarities between the disease in oaks in California and rhododendron in Europe. In both cases, the fungus attacks above ground parts of the plants. In oaks, the fungus enters through the trunk and causes the formation of bleeding cankers on the trunk. On rhododendron plants, the fungus causes similar cankers and spreads from twig tips to the stem base, according to the European researchers.

The researchers have notified agricultural and ecosystem managers in the affected areas of the rhododendron discovery. Research is underway to determine if native rhododendrons - those that have not been imported - are being infected. Research also is being conducted to determine how many other susceptible species may be affected by the fungus.

January 10, 2001

Update on Sudden Oak Death

For more information, go here

January 3, 2001

Henry James Vaux, an innovator of forestry policy and UC Berkeley professor emeritus, dies at 88

02 Jan 2001

By Catherine Zandonella, Media Relations

Berkeley - Henry James Vaux, Sr., a professor emeritus of forestry at the University of California, Berkeley, and former chairman of California's Board of Forestry, died on Dec. 22 in Berkeley after a brief illness. He was 88.

Vaux was best known for his contributions to the field of forest economics and forest policy. His research in forestry formed the basis for the development of modern forest practices and his leadership was pivotal to the evolution of forest policy in California. Over his 45-year career as a forestry economist, Vaux emphasized the need for forestry practitioners to be accountable to the public and for forest management decisions to be based on strong scientific and professional principles.

"Henry James Vaux was one of the most innovative people in the forest policy arena," said Richard B. Standiford, associate dean for forestry in UC Berkeley's College of Natural Resources. "He was one of the giants in forestry in California."

Vaux's views were frequently sought by legislators and policy makers and he played a significant role in the development of California's forestry laws during the 1960s and 1970s. These laws included a forest practices act, which created for the state a public trust responsibility to protect environmental attributes such as soil and water on forested lands. He also played a key role in a forest tax reform act which eliminated tax incentives to harvest timber prematurely, and a forest improvement act which created a fiscal partnership between the state and private forest landowners aimed at improving forest management on private land.

In 1976, then-Gov. Jerry Brown appointed Vaux chairman of the state Board of Forestry, which carried both policy and regulatory responsibilities. He was subsequently appointed for a second term and served in the position until 1983. Vaux's service as chairman was noteworthy for reinvigorating the board's policy-making role. Policies to strengthen the forestry profession, to improve forest management practices, to improve forest taxation and to improve forest resource planning were developed under his leadership.

Throughout his career Vaux received many professional honors. Among them were the Gifford Pinchot Medal awarded by the Society of American Foresters and a Lifetime Achievement Award from the American Forestry Association. He was also a fellow of the California Academy of Sciences and the American Association for the Advancement of Science. UC Berkeley awarded him the Berkeley Citation upon his retirement, and the UC Berkeley College of Natural Resources established the Henry Vaux Forestry Education Center at Blodgett Forest near Auburn. The Center was dedicated in his honor in 1999.

Last fall the College of Natural Resources announced the establishment of the Henry Vaux Distinguished Professorship in Forest Policy. Funds for the professorship were raised through gifts from several hundred of Vaux's colleagues, friends, former students, and family members.

Vaux was born in Bryn Mawr, Pa., in 1912. He graduated with a BS in physics from Haverford College in 1933 and earned his MS in forestry at UC Berkeley in 1935. He acquired extensive practical experience by working as a forest engineer for the Crown Willamett Paper Co. in Portland, Oregon, as a forest economist at the Louisiana Agricultural Experiment Station and as an instructor at Oregon State College (now University) in Corvallis.

He also worked as an economist with the U.S. Forest Service and spent three years on active duty with the U.S. Navy Reserve in Washington, D.C., during World War II. He completed his PhD in agricultural economics from UC Berkeley in 1948 and joined the UC Berkeley faculty the same year. In 1955 he was appointed dean of the School of Forestry and for a decade guided the school through a period of rapid growth. While serving as dean he proposed the formation of the Wildland Research Center (now the Wildland Resource Center) dedicated to research in wildland ecology and management. He retired from UC Berkeley in 1978 but continued to be active in research and teaching.

In the last 25 years of his life, Vaux spent much of his time establishing a family home in the Alexander Valley, a wine-growing region in Sonoma County. He was known to many of his friends and colleagues as Hank.

Vaux is survived by his daughter, Alice Vaux Hall of Portland, Oregon; his son, Henry Vaux, Jr. of El Cerrito, Calif.; his daughter-in-law Prindle A. Vaux of El Cerrito, Calif.; and three grandchildren.

A celebration of his life will be held at 3:30 p.m. on Saturday, Jan. 27 at the Men's Faculty Club at UC Berkeley. In lieu of flowers, the family asks that memorial contributions be made to the Henry Vaux Distinguished Professorship in Forest Policy, c/o the College of Natural Resources, UC Berkeley, CA 94720-3100.


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