Phenology is the study of the timing of natural events. Phenology observers record the date and location of important seasonal events, such as bud burst, flowering, insect emergence and animal migration. Once a Victorian hobby, phenology has never been of much interest to Americans. The USA National Phenology Network (USA-NPN) aims to change that by creating a network of observers, from school children to scientists, to systematically collect and report phenology data.

By combining phenology data with short- and long-term climate and weather data, scientists are better able to track the impact of climate change on the natural world. The USA-NPN was launched in Spring 2008 as a collaboration between the US Geological Survey, the University of Arizona, the University of Wisconsin – Milwaukee and Project Budburst of the University Corporation for Atmospheric Research.

The creation of a national phenology network is not only of benefit to scientists. It can help connect people with nature in a way that is useful to our understanding of climate change. Because of the technical complexity of most science, it is more and more difficult for citizens to be scientists. In the 19th century, many scientific observations were made by hobbyists. The national phenology network offers the promise of restoring the tradition of the amateur scientist.

Phenological observations are easy to make. All you need is a calendar, notebook and perhaps a ruler. The USA-NPN is trying to systematize observations by creating several projects at different levels of sophistication. Project Budburst is suitable for anyone, regardless of experience, and is especially suitable for schools. Project Budburst provides activity guides for native trees and shrubs, native flowers and ornamentals. A set of 18 widely-distributed native species, known as calibration plant species, has been selected to create an extended network of observations with sufficient overlap among observations to allow species responses across the entire country to be compared.

Anybody who is concerned about the impacts of climate change/global warming on our environment should join this effort.  For the investment of a few hours a year, you could help create a very important database that will help scientists study the impacts of global warming on the natural world. Sign up for Project Budburst today!

Picture: Red maple flowers. Picture by Tom Kimmerer

USA National Phenology Network | The Pulse of Our Planet

Is climate change bringing an earlier spring?  Article in SFGate.com

A new atlas of butterfly observations in Britain shows that several southern species are moving north quickly. The atlas, based on 40,000 observations made by a network of volunteers over 10 years shows that species adapted to northern climates are moving north or uphill, while more broadly distributed species are not changing their distribution.

This atlas is an important early sign that species are already adjusting their geographical distribution in response to climate change. These butterflies may be an early warning sign that species and biological communities are under climate pressure, and range adjustments have already begun.  It will be a long time before we see shifts in slower-moving species, including trees.

Observations like these are important because they can improve the ability of biologists to predict the impacts of climate change.  There are not presently enough detailed observations being collected about animal and plant species. Networks of volunteers who can make accurate observations over long periods of time are needed, especially at northern latitudes, where the most rapid range changes are anticipated.

Picture: Citrus swallowtail, Papilio demodocus Esper. Picture by David Cappaert, Michigan State University, Bugwood.org. Used by permission. (This butterfly is not one of the species described in the atlas)

Atlas of butterflies shows southern species head north | Environment | The Observer

The Big Five: emerald ash borer, Asian longhorned beetle, Sirex wood wasp, sudden oak death, hemlock woolly adelgid

Forests in eastern North America are beset with a number of exotic pests and pathogens. Several of these pests and pathogens collectively could have a larger impact on eastern forests than chestnut blight, which killed billions of trees in the first half of the 20th century.  This article is a brief introduction to the Big Five.  Expanded articles will follow over the next month.

There are 4 insects and 1 disease that, in my opinion, represent the biggest threat to eastern forests.  Although there are other major pests and pathogens, both native and exotic, these five either threaten a large number of important tree species or threaten a single very important tree species.  ‘Important’ refers to commercial value of the species, ecological importance or both.

The Big Five (each link is to a longer article which will be updated frequently. NOTE: The linked articles will be available on November 27):

1. Sudden Oak Death (SOD). Caused by the fungus Phytophthora ramorum. A major disease in California, SOD threatens the dominant oak forests of the eastern US.  Transmission is mainly through shipment of stock from infected nurseries in the west. A vigorous inspection and sanitation program in nurseries is slowing the spread of the disease. 
2. Emerald ash borer (EAB). The emerald ash borer is a small, brilliant green beetle native to Asia. It was first found in North America feeding on ash trees in southeastern Michigan in 2002, and is now in 10 US states and Ontario. The beetle kills all ash (Fraxinus spp.), but white, green and black ash are particularly susceptible.
3. Asian longhorned beetle (ALB). The Asian longhorned beetle first appeared in Brooklyn NY in 1996, probably hitching a ride on pallets and other wood containers from China. ALB outbreaks are primarily urban. If the insect spreads into eastern forests, many tree species are threatened. Hosts include maples, buckeyes, willows, elm, birch and sycamore, though other species may be susceptible if ALB reaches high populations.
4. Hemlock woolly adelgid (HWA). The hemlock woolly adelgid, a sucking insect native to Asia, has been in the US sine 1924, slowly spreading to encompass much of the range of eastern hemlock. Although it is spreading slowly, it has the potential to wipe out eastern and Carolina hemlocks throughout their native range.
5. Sirex wood wasp.  The Sirex wood wasp is a major pest of pine trees throughout Europe and Asia. The female wasp lays eggs in pine bark and injects both a toxic mucus and a fungus. The toxin kills tree cells, the fungus grows on the dead cells and the wasp larvae feed on the fungus. Further outbreaks of the wasp are expected, as it hitches rides in wood packing materials. Sirex wood wasps have been found in 15 New York counties, several areas in Ontario, and in Pennsylvania and Vermont. The greatest economic threat is to the southern pine industry, but Sirex wood wasps have not yet been found outside of the northeastern US.

Each of these pests and pathogens poses a threat to particular tree species. Collectively, they threaten the entire eastern forest region.  Emerald ash borer is completely beyond the ability of sanitation and quarantine protocols to control its spread, and it is only a matter of time before the beetle is found throughout the range of ash trees.  Hemlock woolly adelgid is also beyond our capacity to control.  Whether sudden oak death, Asian longhorned beetles and the Sirex wood wasp will reach epidemic proportions is impossible to predict. Vigorous surveillance is so far holding SOD at bay in the east, while Asian longhorned beetles are gaining ground in Massachusetts.

The impact of these pests and pathogens on our forests is closely tied to the impacts of global warming. As the earth warms, habitat conditions for tree species will shift northward. The ability of trees to shift ranges in response to global warming depends on the existence of suitable habitat. The Big Five, as well as other insect and disease problems, may fundamentally alter the structure and function of eastern forests well before the major impacts of global warming occur, and may limit the ability of trees to migrate in response to a warming climate. For example, if warmer conditions allow the hemlock woolly adelgid to become well established at the northern limit of the current range of eastern hemlock, there may be no northward migration of hemlock because trees on the northern fringe will be killed.

Please check back for frequent updates on these pests and pathogens. Although there are many web sites describing each of these individually, there does not seem to be an effort to track information collectively about all these problems.  If any reader knows of such an effort, please post a comment.

Picture credits (all images used by permission):

• emerald ash borer, David Cappaert, Michigan State University, Bugwood.org
• Asian longhorned beetle, Pennsylvania Department of Conservation and Natural Resources – Forestry Archive, , Bugwood.org
• Sirex wood wasp, David R. Lance, USDA APHIS PPQ, Bugwood.org
• sudden oak death (canker on tanoak), Joseph O’Brien, USDA Forest Service, Bugwood.org
• hemlock woolly adelgid on eastern hemlock, North Carolina, picture by Tom Kimmerer.

Henry David Thoreau was an acute observer of the plants of Concord, Massachusetts and Walden Pond. He carefully recorded the abundance and phylogeny of plants in the area. Phylogeny refers to the timing of seasonal activities such as flowering.  Thoreau’s data provides information about species abundance and flowering time of the plants of Concord 150 years ago.

Since Thoreau’s time, several botanists have revisited the natural areas around Concord, creating a unique sequence of observations of change in vegetation over time. Charles Willis and colleagues at Harvard and Boston Universities have analyzed Thoreau’s data and those of botanists since his time and analyzed the abundance of the same species in Thoreau’s old neighborhood over time.  Concord is unusual in still having large areas of land undeveloped or protected since Thoreau’s time.

Willis and colleagues analyzed data for 473 plant species and included information on changes in species abundance, habitat, and sensitivity of flowering to temperature.  They also constructed a phylogeny (relationship diagram) for all the species.

The study shows that climate change has had a profound influence on the plants of Thoreau’s woods. Of the plants that existed in Concord in Thoreau’s time, 27% have disappeared, and 36% have decreased in abundance so much that they are likely to disappear soon. Some of the decline is due to forest succession, some to development, but much of the change appears to be due to climate change. The mean annual temperature has increased by 2.4 degrees C in the last 100 years. Plant species are flowering an average of 7 days earlier than in Thoreau’s time.

The species that have disappeared or declined are more likely to be closely related than one would predict from random chance. The authors explain that this is probably due to the similarity in flowering response to temperature among closely related species.

Some plant species can track seasonal temperature change.  These species will flower earlier when temperatures are warmer.  Other species are not as good at tracking temperature, continuing to flower at the same time every year regardless of temperature.  The good trackers increased in abundance or held their own, while the poor trackers were more likely to decline in abundance.  And the poor temperature trackers tended to be related to one another. This means that poor temperature tracking seems to be a trait of certain plant families, but not of others.

The plants most likely to decline were asters, bladderworts, buttercups, dogwoods, lilies, louseworts, mints, orchids, saxifrages and violets.

This study is interesting because of the connection to Thoreau. It is important because it shows that the risk of extinction due to climate change is shared among closely related plants. Species whose flowering times do not change with seasonal temperature changes are more likely to become extinct (globally or locally) than species that do shift their flowering times.  And, the species that don’t change flowering times are likely to be closely related.

Dogwoods (Cornus spp.) are of particular concern because they are declining for other reasons as well.  Dogwoods are suffering since the introduction of the serious disease dogwood anthracnose, caused by the newly identified fungus Discula destructiva, dogwood populations may be uniquely vulnerable to extinction caused by a combination of climate change and disease. 

Links:

• Phylogenetic patterns of species loss in Thoreau’s woods are driven by climate change – news report, PNAS
• C.G. Willis, B Ruhfel, R.B. Primack, A.J. Miller-Rushing, C.C. Davis. 2008 Phylogenetic patterns of species loss in Thoreau’s woods are driven by climate change. PNAS 105: 17029-17032. DOI: 10.1073/pnas. 080656105

A very important article from Joe Romm at Climate Progress this morning. Evidence is growing that methane in the atmosphere is increasing, and methane is a powerful greenhouse gas (20 times the heat absorption of CO₂ One source of methane may be deep sea-bed deposits that are released as the Arctic Ocean warms.   Joe points out that the evidence is preliminary until the research is published in a peer-reviewed journal, which is planned.

As a general recommendation, if you are interested in the science and politics of climate change, Joe’s Climate Progress blog is the most reliable source of information available.

Climate Progress » Blog Archive » Has runaway climate change begun?

Cross posted at Sustainable Kentucky and Tree Trends.

Andrew Revkin, New York Times reporter and the proprietor of Dot Earth, the Times’ climate change blog, has received the prestigious John Chancellor Award for Excellence in Journalism. The award recognizes Andy’s sustained examination of global warming, including science, politics and economics.

Revkin shares this year’s award with Jane Mayer, a staff writer for the New Yorker. The award, named for the distinguished NBC correspondent, is given to journalists who have a sustained commitment to a subject or story.

Dot Earth has quickly become a must-read resource for anyone interested in the broad implications of global warming.  Revkin has a real talent for interpreting often complex science stories for a lay audience. This talent is very rare in the journalism community today.

Revkin and Mayer will discuss their work at Columbia University on November 18 2008.

Links:

Some Gratifying News – Dot Earth Blog – NYTimes.com

Press Release from Columbia University (pdf)

Cross posted at Sustainable Kentucky/Green Kentucky and Tree Trends.

Spain wil plant 45 million trees from 2009-2012 to slow desertification and combat climate change. The project will cost $127 million and employ nearly 3,000 people. Nearly 1/3 of Spain is in prolonged severe drought and at risk of desertification due to climate change. Spain is also establishing a new research center to fight desertification and climate change.

Spain to plant 45 million trees before 2012 – International Herald Tribune

Spain to set up climate change research institute – Ynetnews

There is no longer any doubt that we live in a world in which humans dominate ‘natural’ processes. We now regulate the atmosphere and earth’s climate through carbon dioxide emissions; control the nitrogen cycle through the use of nitrogenous fertilizers, and are the major force governing the earth’s vegetation. As recently as the early 20th century, most natural processes were indeed governed by nature, but that is no longer the case. Nature has become a wholly owned subsidiary of humanity.

In 2002, the chemist Paul Crutzen proposed that we acknowledge this reality by starting a new Epoch, the Anthropocene. The Holocene, the most recent Epoch, began 10,000 years ago (technically, it began 10,000 radiocarbon years before 1950). Crutzen felt that humans now so dominate natural processes that it was appropriate to use the new term. The term has been widely accepted as an informal description of current conditions.

Jan Zalasiewicz and other members of the Stratigraphy Commission of the Geologic Society of London, writing in GSA Today, have now proposed that geologists and other scientists formally accept the term Anthropocene. Geologists are particularly interested in processes that alter stratigraphy, the orderly deposition of sediments other rock-forming materials. Since humans have dramatically increased erosion, there is now a distinct stratigraphic signal of human influence. Changes in the carbon cycle and global temperatures, alterations of the world biota, and ocean level and chemistry are additional human-influenced factors that are changing stratigraphy.

Zalasiewicz proposes that 1800 be considered the year in which the Anthropocene began. This is an arbitrary date but has the advantage of occurring before or at the very beginning of global human influences on natural processes.

The Anthropocene, an informal designation for the last few years, is now in the process of becoming official. It is a useful term, especially in teaching, that helps clarify that the earth is indeed a human-dominated place.