A newly discovered disease caused by a previously undescribed fungus hitchhiking on a tiny native bark beetle, is infecting and killing hundreds of black walnut trees in California and seven other Western states.
The havoc wreaked by the combined pests, coined "Thousand Cankers Disease," represents a serious threat to black walnut trees, says chemical ecologist and forest entomologist Steve Seybold of the Davis-based Pacific Southwest Research Station, USDA Forest Service, and an affiliate of the Department of Entomology, University of California, Davis.
"The black walnut trees could go the way of the American chestnut or American elm," warns entomologist Lynn Kimsey, chair of the UC Davis Department of Entomology and director of the Bohart Museum of Entomology, which houses one of the largest insect collections in North America.
"By itself the very tiny walnut twig beetle, does relatively little damage," Seybold said. But combined with the aggressive fungus, it can kill a walnut tree in one to three years. Despite the "twig" in its common name, the walnut twig beetle also bores holes in large branches and even in the trunk of walnut trees.
The beetle, Pityophthorus juglandis, native to Arizona, California, New Mexico, and Mexico is widely distributed in California, from San Diego to Shasta counties. Known since 1959 as just another specimen in the drawers of California insect museums, it has emerged on the radar screens of entomologists and plant scientists because it has been found in abundance on dying walnut trees statewide. The disease has also been found in Colorado, Arizona, New Mexico, Idaho, Utah, Washington, and Oregon.
"It's a hard time for hardwoods," said Seybold, who organized and chaired a symposium at the Entomological Society of America's 65th annual meeting, held last fall in Reno. "This is behaving like an invasive pathogen that has run amuck."
Scientists are concerned that the disease may also impact English walnut and California walnut production. "There are hints that the fungus may have infected English walnuts in Utah," Seybold said, "and there are several symptomatic English walnut trees at the USDA National Germplasm collection located in nearby Winters but beyond that we do not know the extent of the threat to the industry."
The fungus, with its barrel-shaped spores, appears to be an undescribed and perhaps exotic species within the genus Geosmithia, said postdoctoral researcher Andrew Graves of the UC Davis Department of Plant Pathology. Graves, part of a Davis-based team working on the project since June 2008, has noted that there are seven named species of Geosmithia.
Colorado State University plant pathologist Ned Tisserat, who placed the fungus in the genus, Geosmithia and named the disease, "Thousand Cankers," told the ESA symposium: "It is really, really a scary disease; it's as bad as butternut (walnut) canker." Butternut (Juglans cinerea) is also known as white walnut.
Graves, who also holds a doctorate in entomology from the University of Minnesota, described the beetle as reddish-brown bark beetle, about 1.5 to 1.9 millimeters long. "It's much smaller in size than a grain of rice," he said. The entrance holes into the black walnut tree look like pin pricks.
"But if you peel back the bark, you'll see the well-developed beetle galleries and blotches of fungal-stained wood and bark that look like a thousand cankers,"said Graves, who is researching the host colonization behavior of the beetle. He described some of the coalescing cankers as "enormous." The cankers widen and girdle twigs and branches, resulting in die back of the tree crown.
Disease symptoms include dark stains on the outer bark tissue that extend into the cambium; yellowing and thinning of the upper crown; wilting of leaves; flagging branches; die back and eventual death, all within three years. Seybold said that the disease is so recently discovered that specialists have not had time to develop and test integrated pest management tools to address the issue. The natural system of attraction of the beetles to the trees and to each other might form the basis of a future monitoring and tree protection toolkit.
"The impact of these beetles and their fungus," Kimsey said, "may be devastating to yet another of our native trees. When I think of the possibility of losing all of the magnificent black walnuts in Davis, it makes me very sad."
The disease complex first gained notice in the Española Valley of New Mexico in 2001 when walnut trees declined and died. Scientists initially attributed the mortality to drought stress. However, when the drought subsided, the massive dieoffs did not.
The beetle-disease complex is associated with widespread deaths of black walnuts planted as street or highway trees in Boulder, Co., Portland, Ore., Prosser, Wash., and several counties in California, including Los Angeles, Sutter, Ventura, and Yolo. It was first noted by scientists in California in 2008.
UC Davis walnut specialist Charles Leslie, a member of the Davis-based thousand cankers disease research team, says two species of black walnut are native to California: Juglans californica (a southern California shrublike black walnut) and Juglans hindsii (the northern California black walnut).
Northern California black walnut is widely planted in Yolo County as an ornamental tree, lining roads and ranches, Leslie said. "These black walnuts are different from the commercial walnuts grown in the Central Valley, which are Persian, commonly called "English" walnut trees grown on black walnut root stock."
California black walnut "is prized more as a shade tree than for its nuts," Leslie said. "To crack the nut, you need to run over it with the family Hummer or hit it with a sledgehammer," he quipped.
However, eastern black walnut is a favorite in the ice cream industry, and the wood is especially prized for furniture and guitars.
To confirm the extent of the disease in the state, the Davis researchers are participating in a federally funded project to collect diseased branches throughout California, particularly in the native ranges of Juglans californica (Los Angeles and Ventura counties) and Juglans hindsii (Mt. Diablo and elsewhere in Contra Costa and Yolo counties. They are also rearing the beetles and studying host colonization behavior. "The beetle appears to pump out at least two generations a year in California," Graves said.
Colorado State University plant sciences professor Whitney Cranshaw, who is on the front lines of the research in Boulder and Denver, said people continually ask him "How can a little twig beetle be killing healthy trees?"
"With Geosmithia," he said. "The fungus is carried into the tree when the beetle tunnels into and wounds the tree. The fungus produces large cankers."
The aggressive fungus girdles the tree and "it's death by 1000 cankers," Cranshaw said.
The attacks generally occur from mid-April through mid-September. At the end of summer, the beetles and the fungus that they carry move into the lower part of the trunk to hibernate.
In their continuing research, scientists hope to establish a baseline of the beetle and fungal populations to understand the full extent of the problem. Native black walnut trees in the western U.S. are important components of the vegetation along streams and riparian zones, Seybold said, so their "loss may have significant ecological implications."
The scientists also advocate research on vector transmission, overwintering biology, an estimation of the risk and threat to the walnut-growing industry in California and to commercially valuable native black walnut trees in the eastern U.S., development of attractive baits, and an insecticide treatment.
Insecticides may prove useful, but only if used prior to the beetle arriving at the tree, Graves said. "Insecticide sprays are of limited effectiveness due to the extended period when the beetles are active, and because the beetles are feeding beneath the bark, insecticides will not be useful in killing beetles that have already entered the tree. Even if the insecticide kills the adult beetles and larvae, the Geosmithia may continue to colonize the bark and phloem."
The scientists also discussed their research this past spring at meetings in Savannah, Georgia (National Forest Health Monitoring Workshop) Spokane, Wash. (Western Forest Insect Work Conference); and San Diego (Pacific Branch ESA Meeting).
- reduced energy costs
- oxygen generation
- stormwater runoff reduction
- air quality improvement
- carbon sequestration
- food production: fruit and nuts
- species habitat for native biodiversity
- soil conditioning with natural compost and root incursion
- urban heat island reduction with shade
and others that can be described qualitatively, such as
- conservation education
- improved human health
- neighborhood revitalization
- stress reduction
- hammock infrastructure!
- climbing courses and virtual playgrounds for kids!
- job training and green jobs
- recycling green waste
- tourism appeal
- natural landmarks and heritage
- natural beauty!
And now --- they capture carbon. I think trees deserve super hero status!American Chestnut Trees
Douglass Jacobs, an associate professor of forestry and natural resources, found that American chestnuts grow much faster and larger than other hardwood species, allowing them to sequester more carbon than other trees over the same period.Jacobs said trees absorb about one-sixth of the carbon emitted globally each year. Increasing the amount that can be absorbed annually could make a considerable difference in slowing climate change, he said.
FURNITURE CARBON SEQUESTRATION: And since American chestnut trees are more often used for high-quality hardwood products such as furniture, they hold the carbon longer than wood used for paper or other low-grade materials.
FOREST CARBON SEQUESTRATION: "Maintaining or increasing forest cover has been identified as an important way to slow climate change," said Jacobs, whose paper was published in the June issue of the journal Forest Ecology and Management.
"The American chestnut is an incredibly fast-growing tree. Generally the faster a tree grows, the more carbon it is able to sequester. And when these trees are harvested and processed, the carbon can be stored in the hardwood products for decades, maybe longer."
At the beginning of the last century, the chestnut blight, caused by a fungus, rapidly spread throughout the American chestnut's natural range, which extended from southern New England and New York southwest to Alabama. About 50 years ago, the species was nearly gone.
New efforts to hybridize remaining American chestnuts with blight-resistant Chinese chestnuts have resulted in a species that is about 94 percent American chestnut with the protection found in the Chinese species. Jacobs said those new trees could be ready to plant in the next decade, either in existing forests or former agricultural fields that are being returned to forested land.
"We're really quite close to having a blight-resistant hybrid that can be reintroduced into eastern forests," Jacobs said. "But because American chestnut has been absent from our forests for so long now, we really don't know much about the species at all."
Chestnuts Compared to Other Tree Species
Jacobs studied four sites in southwestern Wisconsin that were unaffected by the blight because they are so far from the tree's natural range. He compared the American chestnut directly against black walnut and northern red oak at several different ages, and also cross-referenced his results to other studies using quaking aspen, red pine and white pine in the same region.In each case the American chestnut grew faster, having as much as three times more aboveground biomass than other species at the same point of development. American chestnut also sequestered more carbon than all the others. The only exception was black walnut on one site, but the American chestnut absorbed more carbon on the other study sites.
"Each tree has about the same percentage of its biomass made up of carbon, but the fact that the American chestnut grows faster and larger means it stores more carbon in a shorter amount of time," Jacobs said.
SOURCE: Terra Daily
Visit the Green and Sustainable Job Training Catalog at: CaliforniaGreenSolutions.com
On Tuesday, the California Climate Action Registry held a public meeting to discuss the latest version of the Urban Forest GHG Project Reporting Protocol. We had a very good turnout, both in person and online with the Webcast. A number of excellent suggestions were made and noted by the Registry representatives. We think that it would be helpful to reiterate those comments in writing to strengthen the case and provide support in the future should it be necessary.
Subject: Urban Forest GHG Project Reporting Protocol
Performance Threshold
In the Protocol version released July 8, the performance thresholds required of municipal, campus, and utility entities were 0.72% annual net tree gain, 0.58% annual net tree gain, and 0.004 trees planted annually per residential customer, respectively. We believe these levels are too high and would be a significant barrier to participation.
At the public meeting, the Registry indicated that it was considering setting the performance threshold for municipalities and campuses at a level that would require the existing urban forest to be maintained at least at its current population. All project trees that exceeded this level could be registered for credit. The threshold for utilities would be reduced to zero as it is not common practice for these entities to offer tree planting programs.
We support setting the performance thresholds at these reduced levels as we believe they properly represent better-than-average performance.
Co-Benefits: Greenhouse Gases, Energy Production
Although we recognize that for reasons of accounting and accuracy, the Registry cannot verify GHG benefits associated with reductions in energy use due to strategic tree planting or with the use of tree residue for bioenergy, we feel these benefits add significant value to tree planting projects in comparison to other GHG reduction measures.
We therefore urge the Registry to emphasize the value of these benefits in the reporting process and to provide a place on the reporting forms for their estimated value to be entered.
Benefits of Trees
In addition, trees provide many other benefits, some of which can be quantified, such as
- reduced energy costs,
- stormwater runoff reduction, and
- air quality improvement,
and others that can be described qualitatively, such as
- conservation education,
- improved human health,
- neighborhood revitalization,
- job training, and
- recycling green waste.
These additional benefits also add significant value to tree planting projects.
We therefore request that the Registry emphasize the value of these benefits in the reporting process and provide a place on the reporting forms where their estimated value can be entered and a qualitative description can be provided.
Other Types of Entities
Currently, the Protocol only allows for projects undertaken by municipalities, utility companies, and educational campuses to be registered. Often, however, other entities, in particular nonprofit tree advocacy groups, take the lead in spearheading tree planting projects.
At the public meeting, two potential concerns for including other entities were mentioned: the questionable longevity of other entities, especially nonprofit organizations, and the lack of available data for setting a performance threshold. We note first that the entire premise of the Registry relies on assuming the longevity of the nonprofit Registry itself. Therefore, we consider this concern to be shared equally between those doing the reporting and those accepting and verifying the reports. We encourage the Registry to determine whether sufficient historic data exist and whether a suitable matrix can be developed to create a performance threshold before deciding to exclude other entities.
We therefore encourage the Registry to consider adding other entities, in particular nonprofit tree advocacy groups, to the list of participating entities.
SOURCE: California Releaf
Watch a 6-minute trailer for the DVD "Planting the Vision" below.
> Watch the Natural Heroes Fruit Tree Tour Promo on the Natural Heroes site
A couple elegant, tall, stately trees are my constant companions as I type to you. When my eyes need a break from the computer screen, they turn to these two friends. I watch their leaves dance in the wind. And turn a million shades of green as the seasons give them new life, abundant growth and then sap their maturity and cause them to flutter to the ground in the late summer and autumn breezes.
Yes, I love trees. Not just because of their beauty...but because the more I learn about trees, the more I admire their everyday work, their community spirit and their productivity. They take sunshine and rain from the sky and turn it into food for butterflies and birds and mammals and yes, us.
They crack rocks open with their delicate new roots. They create pathways for water and nutrients to filter down into deeper and deeper layers of soil. And then they shed their leaves annually to create compost and new soil.
Trees give shade. They give fruit and nuts. They give twigs to the birds to build nests. They give deer scratching posts. They cradle homes in their branches for birds and beetles and spiders and lizards... and some even grow in swamps and lakes and give homes to fish and frogs and snakes.
Tall trees like redwoods pump moisture up to the tipty tops of their branches further than engineers have been able to duplicate with our high tech pumps.
... have you caught the tree fever yet? Do you have a favorite friend outside your windows that gives you graceful, gentle respite? I hope you do...and if you don't, I hope you will plant one and watch it grow into a stately young adult...rejoicing with it every season and dancing with it on every breeze!
California ReLeaf monitors state and federal legislation in order to inform the urban forestry community of opportunities to influence public policy on behalf of urban trees.
In 2006 California ReLeaf hired a professional lobbyist to assist with its state-level efforts. As a result of its work, $20 million was designated for urban forestry programs under California Proposition 84 passed in 2006.
California Releaf also coordinates California ReLeaf Network, an alliance of urban forestry groups throughout the state. This alliance has been instrumental in raising the profile of urban forestry in the state and a key part of California ReLeaf's advocacy strategy.
BACKGROUND
California ReLeaf was founded in 1989 as a program of the Trust for Public Land and was incorporated as a separate 501c3 nonprofit in 2004.
California ReLeaf works statewide to promote alliances among community-based groups, individuals and government agencies to protect the environment by planting and caring for trees. It also serves as the state's volunteer coordinator for urban forestry in partnership with the California Department of Forestry and Fire Protection.
Programs and services include:
* Coordinating California ReLeaf Network, a statewide alliance of urban forestry groups
* Administering a state grant program
* Publishing a quarterly newsletter, California Trees
* Providing assistance, information and referrals to individuals, organizations and agencies on urban forestry management issues
* Monitoring state and federal legislation and keeping the urban
forestry community informed of opportunities to influence public policy
on urban forestry
COMPONENTS
Hiring a professional lobbyist
From its inception, California ReLeaf was involved in advocating on
behalf of urban forestry. In 2006, California ReLeaf decided that
hiring a professional lobbyist would greatly improve effectiveness at
influencing state legislation on urban forestry.
Since California is a large state with a wide range of environmental issues, California ReLeaf, with a staff of three, found it difficult to stay on top of all the issues and proposals that affected urban forestry. Although California ReLeaf had many partners who worked with them on urban forestry issues, it needed someone to spearhead its efforts.
With the encouragement of other urban forestry groups, California ReLeaf hired a lobbyist who specialized in conservation issues and was willing to work with them at a reduced rate.
Martha Ozonoff, Executive Director of California ReLeaf, says that this decision has been critical in its advocacy efforts.
"Hiring a lobbyist has definitely increased our ability to be effective. You can lobby on your own. You are not required to have a professional lobbyist. But this has helped us stay on top of fast-paced decisions and has given us inside information about what different legislators are interested in and how to approach them. Our lobbyist has helped us see where we can connect to other environmental issues," Ms. Ozonoff says.
Ms. Ozonoff says whether or not your organization needs a professional lobbyist may differ from state to state. She recommends talking with larger environmental organizations in your state that have lobbyists on their staff such as the Trust for Public Land, the Nature Conservancy or the Sierra Club. Get recommendations from them on whether or not you need to hire a lobbyist and on potential candidates.
Making your case
Once the lobbyist identifies what legislation to follow and who the key
players are, California ReLeaf meets with key players including
legislators and their staff, testifies at committee hearings, sends
letters and emails, makes phone calls and encourages organizations in
the California ReLeaf network and other groups to support legislation
and other relevant initiatives, including funding propositions.
Ms. Ozonoff emphasizes that working with a network of urban forestry groups brings enormous value in supporting advocacy initiatives. California ReLeaf Network has approximately 90 member organizations located throughout the state. This allows California ReLeaf not only to harness the support of more constituents throughout the state, but also helps them target voters in specific localities where key legislators reside.
Funding
California ReLeaf funds its advocacy efforts through private foundation
monies in its general operating account. Government funds cannot be
used for lobbying.
RESULTS
California ReLeaf is particularly proud of its advocacy efforts which helped to ensure that "at least" $20 million funding was designated for urban forestry under Proposition 84 passed in 2006.
In addition, in 2007 California ReLeaf helped spearhead a letter-writing campaign thanking Governor Schwarzenegger for restoring $10 million to the Environmental Enhancement and Mitigation Program, which provides public funds for urban forestry and other natural resource projects that reduce the impact of transportation projects on local communities. This year, the funds are being presented as part of the Governor's budget, thereby virtually assuring their passage. California ReLeaf believes that its "thank you" campaign may have played a part in the governor's decision.
California ReLeaf is currently sponsoring a bill in the state legislature to update the state Urban Forestry Act of 1978. This will be the organization's first effort at sponsoring legislation.
LESSONS LEARNED
1. Research your state to determine whether or not you need to hire a lobbyist. California ReLeaf says hiring a lobbyist was essential for them.
2. Nonprofits CAN advocate and lobby. Don't be paralyzed by the fear of violating IRS rules. Read the regulations and get advice but remember that both advocacy and lobbying are allowed within certain limitations. The rules may not be as restrictive as you think.
3. Advocacy and lobbying is easy. Do not be intimidated by the process.
4. You are the expert on your cause and its most passionate supporter. Make use of that.
5. Remember to say thank you to all the people who support your efforts.
6. Stay on top of legislation. Understand the process and realize that changes can happen quickly and often. You need to be vigilant.
7. The benefits of advocacy are enormous. It raises the visibility of your cause and your organization. It helps refine your message and increases your organization's credibility and reputation.
Contact Information:
Martha Ozonoff, Executive Director
California ReLeaf
P.O. Box 72496
Davis, CA 95617
Phone: (530) 757-7333
Fax: (530) 757-7328
The planting was the third NeighborWoods planting of the year around the city, said Diane Losavio, executive director of Baton Rouge Green. Jared Liu, director of programs at the Washington, D.C.-based Alliance for Community Trees that oversees the NeighborWoods program, was on hand to help with planting and to discuss the connections between affordable housing and trees.
Liu said a landscape plan had been developed to place the right trees in the right places around the houses. A tree that provides ample shade planted close to a home can cool it down in warm weather, reducing energy costs, he said. "And shaded homes will sell faster," he added.
Losavio said volunteers planted a mixture of nuttall oaks, willow oaks, sweet olives, magnolias, red maples and crape myrtles around the houses on East Polk Street.
Residents are scheduled to move into the houses within the next few months, said Richard Murray, director of the East Baton Rouge Housing Authority. Four of the 14 houses will be rented to tenants, Murray said. The other houses will be put on the market to sell at prices ranging from $79,000 to $99,000.
Rose Netter, 62, who will be moving into a house on the corner of Polk and Kansas streets, came out to watch the planting Saturday. "I'm very emotional," Netter said. "I'm just so moved to see all the people that are helping." A first-time homeowner, Netter currently lives in her mother's house, down the street from the development. She will be moving into her new house with her daughter and granddaughter, she said.
Kristina McCray, 21, volunteered Saturday with other members of Delta Sigma Theta, a public service sorority at LSU. "I never knew how to plant trees before," she said as she spread mulch over the base of a red maple. "And it's helping the community." There were some veteran planters in the crowd, such as 17-year-old Malavika Balachandran.
Picture by Travis Spradling/The Advocate
Stephen Shurtz, left, a urban forestry and landscape manager with the
city-parish Department of Public Works, helps LSU Delta Sigma Theta
sorority members Courtney Boss, center, and Kasielynn Smith, right, as
they tug a tree out of its pot before placing it into a pre-dug hole.
The McKinley High School senior has helped out with many plantings since starting an environmental club at her school. Wearing green gloves, she and her sister, Devika Balachandran, 15, prepared the hole for the tree, breaking up clumps of clay with spades. "We didn't have to dig the holes today," Malavika said thankfully. "That takes a really long time."
Related Resources:
The Advocate
East Polk NeighborWoods Tree Planting
Baton Rouge Green
Non-native invasive plants are species whose introduction outside their ecological homes causes economic or environmental harm. They quickly establish themselves in a new habitat that has favorable conditions and no natural predators to balance their growth and spread. They can also threaten or eliminate the ability for native species to thrive because they DO have natural predators and have evolved to live with moderate growth in a robust community of competitive species.
That number keeps climbing with international trade, travel and shipping that move plants, animals and disease organisms with globalization.
Native plants contribute to natural systems, but invasive species can upset delicately balanced systems of water availability, sunlight, and soil quality. Many natives have adapted over time to tolerate local weather conditions and often feature deep root systems which can find water during drought conditions.
Invasive trees, shrubs and vines can spread not only their own species, but enable diseases to spread more rapidly and impact blight, rot and insect damage, as well as impact water supplies, pollinator migrations and native wildlife species habitat.
There are many local, regional and national conservation organizations that work to preserve native plants and species, as well as eradicate invasive populations. Nature is a very "localized" natural system -- and local action and vigilence are required to monitor and reclaim degraded land systems.
The Conservation Foundation - Illinois
The Conservation Foundation is a nonprofit land and watershed protection organization established in 1972 by business and community leaders, The Conservation Foundation is a not-for-profit land and watershed protection organization. Our headquarters are located in Naperville, Illinois, on a 60-acre working farm, and a program office is located in Montgomery, Illinois.
The mission of the Foundation is to preserve open space and natural lands, protect rivers and watersheds, and promote stewardship of the environment in Illinois.
The Conservation Foundation
Dickson-Murst Farm
2550 Dickson Road
Montgomery, IL 60538
Phone: (630) 553-0687
http://www.theconservationfoundation.org/
