HRT 300 : Articles to Read

Please familiarize yourself with these articles – at your leisure……



MARCH 2, 2010, NYT



Imagine the Earth without grasses.

There would be no lawns or meadows. No prairies. No savannahs or steppes. No wheat fields or rice paddies. No sugar cane. No sheep, elephants or horses. No people.

We live in the age of grass. Indeed, from our point of view, the evolution of grasses was one of the most momentous events in the history of the Earth. Which is why I’m nominating them for Life-form of the Month: March. Let’s limber up with a few facts. In general, grasses spread their pollen by wind, so they are not dependent on bees or other insects. Grasses also grow fast, and can easily colonize patches of bare ground, or move into a landscape after a fire. They can withstand being eaten (or mown) better than most other plants, because their leaves grow from the base, not the top.

Like all plants, they make energy from the sun by means of photosynthesis. However, grasses have repeatedly evolved a variation — known as C4 photosynthesis — that uses less water, and is thus a particular advantage in hot, dry places, or when carbon dioxide levels are low. This has allowed them to flourish in difficult habitats, like rocky outcrops and dry soils. One other detail: grasses fill their leaves with silica. That is, they are factories for tiny opals.

As a group, grasses have been wildly successful. Today, the grass family contains more than 10,000 species — that’s more species of grass than species of bird — and grasslands cover about a third of the planet’s landmasses. (“Grassland” refers to an ecosystem, like prairie, where grasses dominate; it doesn’t mean they are the only plants there.) Grasses can be tall (think bamboo) or short (think lawns), and they include our most important crops. Rice, wheat, rye, oats, maize, millet, barley, sorghum and sugar cane are all grasses.

We humans are dependent on grasses: we get more than half our calories directly from the tetrad of rice, wheat, maize and sugar cane, and we feed grasses to our sheep, goats, horses and cows. But I’m getting ahead of myself.

The early history of grasses is obscure. However, we do know that they blew onto the scene relatively late — around 80 million years ago, shortly before the dinosaurs went extinct. In evolutionary terms, that’s yesterday.

And having arrived late, their rise to prominence got off to a slow start. If you climbed into your time machine and set the dial for 55 million years ago, you wouldn’t find much in the way of grasses when you got there: at that point, they were still minor players on the Earth’s stage. But by 15 million years ago, that had changed. Grasslands had become abundant.

Exactly why this happened is a matter of debate. But whatever the reasons, the effect on other lifeforms has been profound.

Grasses affect the landscape both above and below the surface of the Earth. Below: they alter the texture of the soil. Grassland soil is typically characterized by small crumbs that are rich in organic matter. This is partly due to the way that grass roots grow, and partly due to the animals that grasses encourage — like earthworms and insects. Many of our richest agricultural lands were made so by grasses.

Above ground, grasslands create wide open spaces where large animals can run fast and go about in big herds. Hence, the spread of grasses triggered the evolution of big, herding mammals with long legs and hooves — horses and antelopes, for example. Moreover, all those opals are hard to eat: they wear down teeth. So the rise of grasses was also met with the evolution of “hypsodonty” — long teeth.

(Just as grasslands sculpted the evolution of certain mammals, so too mammals sculpted the evolution of grasslands. Many mammals eat young trees — and thus prevent trees from invading a grassy area. Elephants can — and sometimes do — uproot big trees. The high opal-content of grasses is, in part, an evolved response to being eaten.)

Now pause for a moment to imagine these savannahs with their big herds of galloping mammals. For these are also the landscapes in which, perhaps, our earliest ancestors stood on two legs and learned to hunt — though again, this is a matter of debate.

Yet regardless of how much grasses shaped our earliest evolution, in the recent past they have transformed us. We usually talk of our domestication of grasses, and the ways in which we have evolved them: we have made plants with bigger, more nutritious seeds that don’t fall to the ground, for example.

But their effect on us has been far more profound. Our domestication of grasses, 10,000 years ago or so, allowed the building of the first cities, and marks the start of civilization as we know it. Grasses thus enabled the flowering of a new kind of evolution, a kind not seen before in the history of life: the evolution of human culture.

- – - – - – - – - -


March 9, 2010, 8:30 PM / The New York Times


Birds do it. Bees do it. Beetles, bats and light summer breezes do it. I refer, of course, to that raunchiest of sex acts: the pollination of flowers.

When it comes to sex, plants have more headaches than the rest of us. One problem is that they can’t travel about to find a mate — they are, after all, rooted to the spot — so they have to depend on intermediaries to bring egg and sperm cells together.

For mosses and ferns, the intermediary is water. For conifers like pine trees and cypresses, the intermediary is wind. But for most flowering plants, the intermediaries are animals.??Flowering plants are the largest, most successful group of plants on the planet today. There are thought to be more than quarter of a million different species — nearly 10 times more than all the other types of plants added together. (To put things in perspective, the number of living species of fish, amphibians, reptiles, birds and mammals combined is less than 58,000.) The flowering plants include roses and waterlilies, grasses and oak trees, tulips and orchids. They include, in short, most of the plants that come to mind when one thinks of vegetation.

It was not always thus. Before the mid-Cretaceous, 100 million years ago or so, flowering plants were scarce: conifers and their relations ruled the landscape. But then, for reasons that are not well understood, flowering plants upstaged all others, and the Earth came into bloom.

Flowering plants were not the first to seduce animals into spreading their pollen for them. Fossils suggest that some earlier groups of plants, now extinct, had evolved a dependency on insects like scorpionflies. Nonetheless, the earliest flowers appear to have been pollinated by insects, and the full-scale blossoming of flowering plants coincides with the rise of animals as go-betweens. Bees, for example, buzzed onto the scene with flowering plants; the evolutionary history, and success, of both groups is intimately linked.

The appearance of flowering plants brought a new flamboyance to the planet. Flowers pollinated by animals tend to be big and colorful; they often smell. (To a human, flowers pollinated by bees typically smell pleasant; flowers pollinated by flies tend to smell foul, like rotting meat.) Often, flowers offer something for the animal to eat — a sip of nectar, perhaps. Sometimes, they provide heat.

(One plant that heats its flower is Philodendron solimoesense, an Arum from the South American tropics. In doing so, it turns itself into an assignation hotel for scarab beetles. The beetles arrive in the evening, spend the night feeding and mating, spend the morning recuperating and head off to a new flower later on — complete with pollen from their host. Sure enough, the heat saves the beetles energy. Beetles in a heated flower don’t have to use as many calories to keep warm as they would if they spent the night outdoors.)

Yet, from time to time, flowering plants abandon their animals, evolving instead to throw pollen to the wind. Wind-pollination — if you’re a vocabulary fiend, the technical term is “anemophily,” meaning lover of wind — has evolved at least 65 times in flowering plants, and around 10 percent of the species do it. Indeed, as I mentioned last week, many grasses are pollinated by the wind.

It’s not clear what causes this transition, though there are several ideas. One is that it happens in plants that, although generally pollinated by insects, already have a small capacity for wind pollination — small, light pollen grains, and flowers that can, in principle, catch pollen if it floats past on a breeze. Then, the balance between insects and wind can easily shift. In a tropical forest, for example, the advantages of insects are great: they provide highly targeted pollen-delivery in a complex milieu. But in big open spaces, the wind may do a better job — especially if the climate is inhospitable, and insects are few. Such circumstances may cause a shift away from traits that lure insects, and enhance those that seduce the wind.

A plant that has sacked bees or other insects can make its flowers smaller, less colorful and more aerodynamic. Liberated from the expense of making nectar, it can make more pollen instead. A bee, after all, can only carry so much pollen at once. The wind is not so limited.

And wind-pollinated plants tend to produce huge quantities of pollen. Whereas animal-pollinated plants produce a median of 3,450 pollen grains for every ovule, wind-pollinated plants produce almost 10 times as much. No wonder wind-pollinated plants are the chief causes of eye-itching, nose-tickling human misery. (It’s not just the anemophilous flowering plants that are to blame, though. Wind-blown cypress pollen is a major cause of allergies in some parts of the world.)

This massive production of pollen is usually put down to the inability of wind to make reliable deliveries.

Charles Darwin himself suspected the wind of being a fickle and inefficient messenger, and that view has largely held until this day. But there is little actual evidence that wind-pollinated plants have more difficulty getting themselves fertilized than other plants do. (Indeed, plants seem adept at plucking pollen of the right species out of the breeze. How they do this isn’t known.) Moreover, in animals, large numbers of sperm tend to evolve when competition between different males to fertilize a female’s eggs is fierce. In many wind-pollinated species, plants flower all together, and for a brief time. Perhaps wind-pollinated plants face greater competition from their rivals.

But whatever the causes, I’m glad that most plants have not sacked their bees. In a world pollinated only by gusts and breezes, spring would be less beautiful. And, for many of us, it would also be more tortured.

- – - – - – - – - – - – -

Article #3

By Kirsten Weir / The Scientist, December 2009

No kissing here: Mistletoe appears to be meddling with the stately spruce’s hormones.


For the white spruce tree (Picea glauca), mistletoe is the kiss of death.

When Barry Logan, an associate professor of biology at Bowdoin College, began studying the interaction between white spruce and the parasitic eastern dwarf mistletoe (Arceuthobium pusillum) 10 years ago, he figured the mistletoe sapped the spruce of food and water until the tree could no longer sustain the drain. “When I entered into this, I mostly thought about the parasite as just a sink for resources,” he says. He soon discovered the system was much more complex. Ten years on, he’s drawing some surprising conclusions about how the petite flowering plant brings down the stately spruce.

Seeking out mistletoe-infected spruce in coastal Maine forests isn’t much of a challenge, Logan says. The parasite causes trees to grow twisted, tangled branches called witches’ brooms. These misshapen branches are dead giveaways that mistletoe is wreaking havoc on the tree’s growth and development.

Dwarf mistletoe isn’t always lethal. Forty-two species (including the eastern variety) exist, and they impart varying degrees of harm on their favorite host trees. In Washington and Oregon, western hemlocks show evidence of having weathered infections of hemlock dwarf mistletoe for 80 years or more, Logan says. White spruce, on the other hand, succumb to eastern dwarf mistletoe in 15 or 20 years.

Maine’s coastal forests may be uniquely vulnerable, Logan says. A century ago, farmers felled the native mixed-hardwood forests along the coast to make room for sheep farming. These pastures were quickly abandoned, and white spruce (which thrives in full sun and enthusiastically colonizes old fields) moved in to the vacant spaces. Today these forests contain dense, monospecific stands of very mature spruce trees—a perfect recipe for damaging mistletoe infections. As the aging coastal white spruce succumb to the infection, Bill Ostrofsky, a forest pathologist at the Maine Forest Service, says he expects that the composition of these forests will change—a return, perhaps, to the oaks and other hardwoods that disappeared from the coastal forests during colonial times.

But historical symmetry offers little consolation for the white spruce. In addition to growing tangled witches’ brooms, the individual needles on infected trees are much smaller than normal (Plant Biol, 4:740–45, 2002). The parasite disturbs the tree’s water balance and stunts tree growth overall. But it’s a certain counterintuitive habit that makes mistletoe infections so deadly for the white spruce, and so intriguing to the scientists.

Trees typically respond to parasites and pathogens by shedding infected branches and sending resources to unaffected limbs. Other tree species respond to mistletoe in this manner, and white spruce, too, react this way when attacked by other pathogens. When plagued with dwarf mistletoe, however, white spruce ship water, nutrients, and sugars to the infected branches, at the expense of the uninfected boughs. “Something about the mistletoe is overriding the white spruce control mechanisms,” says James Lewis, a plant ecologist at Fordham University, who has been collaborating with Logan for the last 4 years.

The mistletoe, it seems, may be meddling with the tree’s hormones. In a not-yet-published study, Logan and his team discovered that needles on infected white spruce branches have twice the concentration of cytokinins as do uninfected branches. These growth-promoting hormones trigger branching and direct the movement of resources into the branch. Infected branches also have significantly reduced concentrations of abscisic acid, a stress-related hormone that some studies have linked to the shedding of old branches. “All of this comes together nicely,” Logan says, to explain how witches’ brooms form and thrive.

Exactly how the mistletoe is manipulating the tree’s hormones remains to be seen. “I think it’s possible that the mistletoe is moving hormones into the host and not just withdrawing resources,” he says. He hopes to undertake more hormonal analysis to get to the bottom of the interaction between parasite and host.

Understanding this parasitic interaction—and the spruce’s maladaptive response—could go a long way toward helping scientists better understand plant ecology in general, the researchers say. “The way [mistletoe] is killing the tree is so different from what we usually see. I think that’s one of the reasons why this is a nice system for addressing broader issues of how plants interact with other organisms,” Lewis says.

“There’s an interplay between [host and parasite] which I didn’t appreciate when I first tackled this project,” Logan adds. “It makes it more interesting, and more complicated.”

- – - – - – - – - -

Article #4

A FIELD BINDWEED “TUTORIAL” : Convolvulus arvensis, Convolvulaceae, the Morning Glory family

from Richard Mabey’s “Weeds,” p. 68: “The bindweeds are a family that have perfected an extensive and daunting battery of survival techniques. Their sinuous roots and climbing stems, which can smother other vegetation, earned them the uncompromising vernacular name ‘Devil’s guts.’ Before the development of chemical herbicides (but see below), the field species, Convolvulus arvensis, was amongst the most intractable of arable weeds. It’s a beguilingly attractive plant, with pink, white or candy-striped bellflowers which have a light almond fragrance in the sun, and whose nectar attracts a large number of insect species. The twining stems may be a clue to its wild origins. They can reach at the most about three feet in height, nothing like the tree-climbing hawsers of the hedge bindweed, and suggest that Devil’s guts may have begun its conquest of farm and garden from areas of disturbed soil studded with low bushes.

“Field bindweed has an almost foolproof insurance portfolio,a range of reproduction and regeneration techniques to meet every possible contingency. Each plant produces about 600 seeds, some of which germinate in the summer and some in autumn. Or, if buried deeply enough, at any time over the succeeding forty years. Once the seedling is established and rooted it extends horizontally by means of underground stems. The whole underground system may spread over thirty square yards in a single season, and the vertical roots penetrate downwards more than eighteen feet. New above-ground shoots can spring either from the underground stems or directly from the roots. Cutting the roots with a hoe or plough temporarily weakens the plant, but also promotes new shoots. The response by the plant is fast and decisive. Within a few seconds a milky latex oozes out of the wound, and clots over the cut surface to form an antiseptic seal, a callus. Within days dormant shoot-buds close to the wound have begun to swell and form new roots and leaf stems. This happens with even the tiniest fragment of any part of the plant. A bindweed root or stem chopped into a hundred pieces by a frustrated gardener is simply the starting point for a hundred new plants.

Above ground, the tip of the twining stem hunts for light, curling round any vertical objects…for support…If the twining stems are partially buried by soil or stones, they can take root. If they’re repeatedly cut off the plants compensate by taking on a bushy form and generating multiple branches. If they’re eaten by cattle, chemicals in the stem recognize the growth hormones in the animal’s saliva and are stimulated into even faster growth.”

from the Internet:…..Aceria malherbae, is a microscopic mite used as a biological control agent for field bindweed.  This bindweed mite can only feed on field bindweed and closely related wild morning glories. It does not damage other plants and can only survive on bindweed.

Field bindweed showing damage caused by the bindweed mite.  The Bindweed mite feeding causes the formation of gall-like growth of plant leaves. Leaves of infested plants are thickened, and have a “fuzzy” texture. In heavily infested plants, the shoots are misshapen and growth is severely stunted. Recently infested plants have newly emerged leaves that appear folded. The thickened texture and fuzzy appearance are good diagnostic characteristics to identify bindweed mite.

- – - – - – - – - -

Article #5

Wake Forest researchers discover pokeweed could help electrify the Third World

BY AMBER VEVERKA - Correspondent
Published in: Science/Technology
POKE BERRY POKEBERRYThe pokeberry is a common weed in Southeastern states. The juice from its poisonous berries could be used for low-power solar cells in developing nations in need of renewable energy.

David Carroll, director of the Center for Nanotechnology and Molecular Materials, examines a solar power cell in 2008 that has a polymer coating. He and his students have investigated cell coatings made from berries of the pokeberry weed: The juice is purple, a color that absorbs more photons from sunlight. It produces current when sandwiched in the spot where silicon would go.

When David Carroll wanted to find a way to make low-cost solar panels, he discovered he needed look no further than his own backyard.

In a weedy part of his Winston-Salem lot, pokeweed grows in wild, red-caned riot. Birds love the purple berries, and soon, so did Carroll. Because with pokeberries, the Wake Forest University scientist believes he’s found a key to supplying electricity to parts of the developing world.

One Friday last year, Carroll, director of the Center for Nanotechnology and Molecular Materials at Wake Forest, was meeting with his students, brainstorming ways to get solar power to impoverished communities.

Traditional silicon solar panels are great, they agreed. But to make them, you need costly materials and a high-tech factory.

“We were sitting around thinking about the problem of how do you make it really, really cheap – and you can’t get around the fact that (if you do), it’s not going to be a very good solar cell. So it has to be very cheap to be worth it,” Carroll recalled.

Natural dyes from plants rich in compounds called flavonoids can produce electrical current when sandwiched between the layers of a solar cell, in the spot where silicon would normally go.

Carroll’s team set out to find a plant whose dye would work the best – and which could be grown all over the world. The team focused on red or purple plant dyes, since those colors absorb the most photons from sunlight.

Strawberries didn’t work. Besides, Carroll said, they wanted “to stay away from things people would eat,” focusing instead on a plant that would have multiple uses. Eventually the team tried poke. Pokeweed, whose berries and mature leaves are poisonous, can be eaten if cooked properly when shoots are small, making it a dual-purpose crop that could make sense in the developing world, Carroll said.

“Other people have done similar things, so we’re not the only ones who have done this,” Carroll said. “But we’re the only ones who have (used) very raw and unprocessed stuff.”

How unprocessed?

“You pick (the berries) and squish them,” Carroll said. “You’ve got to get the big chunks out. That’s pretty easy to do.”

The team painted the purple juice on a transparent conductor, a piece of glass or plastic with an aluminum zinc oxide coating. That was sandwiched against a second plate covered with a very thin metal coating with a dilute solution of iodine between and placed in the sun.

Carroll and the students soon saw the results: poke power. They produced their first test pieces last summer.

“A large panel of this stuff, a couple of meters on each side, could produce 5 to 10 watts pretty easily. That’s going to charge a battery up pretty fast,” Carroll said.

To be sure, that’s a very low-power solar panel – creating enough power to run a small light bulb through the night, perhaps.

But that low efficiency is just the point, Carroll said.

“Right now in many places in the world, where you’ve got a medical facility that’s trying to operate at night, they can’t – they have to shut down. In order to have a light in a lot of these places, people will walk five to 20 miles to get enough gasoline to power a generator. These panels will provide enough light the same as a generator,” he said.

“It’s not super-high performance, but it’s renewable. What we really wanted to do is find just how basic we could make it and how much power we could get out of it.”

Carroll’s team found out just how basic a pokeweed panel can get when they were contacted last year by a sixth-grader in Elizabeth City. Grace Taylor, now 12, was looking for a science fair project. She wondered: Could she make electricity from berry juice?

Carroll passed along what he knew and Grace soon was picking pokeberries in her own backyard. Working in her kitchen, she built a berry-juice solar cell and attached a volt meter. Then she shone a lamp on it to mimic sunlight and watched as her homemade cell produced electricity.

Grade-schooler weighs in

Grace won first place in a local science fair, took second place in regionals and went on to enter her project at the state level. She compared the pokeberry results with those she got from Virginia creeper berries (the creeper won, but its downside, as far as Carroll is concerned, is that it isn’t a foodstuff). Grace pronounced the whole experiment “pretty cool.”

For Carroll, a sixth-grader’s experiment proves he’s on the right track.

“You don’t need a huge factory to make solar cells out of this,” he said. “I think the neat part of this is it’s not always about the technology. The technology doesn’t work that well. But it changes the microeconomic climate. If your nation can’t produce large silicon solar cells, it doesn’t matter how good they are.”

The pokeberry cells wouldn’t be a big money-maker for a corporation and that means a foundation would probably have to back development.

“You’re really doing this for the Third World,” Carroll said, “and your return on investment is you lower their carbon emission and raise their standard of living.”

- – - – - – - – - -

Article #6

Monsanto’s Bt Cotton Kills the Soil as Well as Farmers

Biosafety refers to ensuring that GMO’s do not harm the environment or health.

The soil, its fertility, and the organisms which maintain the fertility of soil are a vital aspect of the environment, especially in the context of food and agricultural production.

A recent scientific study carried out by Navdanya, compared the soil of fields where Bt-cotton had been planted for 3 years with adjoining fields with non GMO cotton or other crops. The region covered included Nagpur, Amravati and Wardha of Vidharbha which accounts for highest GMO cotton planting in India, and the highest rate of farmers suicides (4000 per year).

In 3 years, Bt-cotton has reduced the population of Actinomycetes by 17%. Actinomycetes are vital for breaking down cellulose and creating humus.

Bacteria were reduced by 14%. The total microbial biomass was reduced by 8.9%.

Vital soil beneficial enzymes which make nutrients available to plants have also been drastically reduced. Acid Phosphatase which contributes to uptake of phosphates was reduced by 26.6%. Nitrogenase enzymes which help fix nitrogen were reduced by 22.6%.

At this rate, in a decade of planting with GM cotton, or any GM crop with Bt genes in it, could lead to total destruction of soil organisms, leaving dead soil unable to produce food.

The ISAAA in its recent release has stated that there are 7.6 mha of Bt-cotton in India. This means 7.6 mha of dying soils.

The impact of GMO’s on soil organisms is not commonly studied. This is a vital lacunae because Bt toxin crops such as Mon 810 corn or Bt-cotton or Bt Brinjal have serious impact on beneficial soil organisms.

The government of India is trying to grant approval to Bt Brinjal without Bio safety studies on impact on Soil organisms. The European Commissión is trying to put pressure on GMO free countries to introduce Mon 810.

The Navdanya study the first that has looked at the long term impact of Bt cotton on soil organisms is a wake up to regulators worldwide. It also shows that the claims of the Biotechnology industry about the safety of GM crops are false.

- – - – - – - – - -

Article #7

Worm-Eating Plant Uses Underground Leaves To Capture Prey

Worm Eating Plant


It may not look like much, but this little plant is a meat-eating killer. Scientists took awhile to figure that out because of its never-before-seen adaptation: instead of a gooey bug-trapping “mouth” like that seen in Venus Flytraps and other familiar carnivorous plants, little Philcoxia minensis sends some of its leaves under the sand, where they await passing worms to gobble up.

In a study published January 9 in Proceedings of the National Academy of Sciences, scientists detailed their discovery, which came after suspicions that the plant—native to the Brazilian savannah—was getting more nutrients than its small root would provide. It was unusual that some of its leaves—normally used to gather sunlight—grew underground, especially since they were covered with a sticky substance similar to secretions of other meat-eating plants.

For the study, the researchers tagged tiny nematode worms with nitrogen and watched as the plants absorbed it. There are several novel aspects to this finding. The underground leaves, naturally, are new, but so is the plant’s dependence on nematodes. Co-author Rafael Oliveira told Science magazine, ”When I first saw the results, I couldn’t believe those underground leaves were actually eating nematodes.”

The study has launched a conversation about the adaptation of meat eating in plants. It turns out that becoming a carnivore might not be such a complicated adaptation as we thought. Co-author Peter Fritsch said, “There is a balance point where if there are not enough nutrients or not enough light it can push a plant toward carnivorous syndrome.”

Fritsch expressed suspicions that there might be many more killer plants out there than we’ve identified, telling Nature magazine that “This leads to the question of whether there are other carnivorous plants out there in families not known for carnivory.”

- – - – - – - – - -

Article #8

MOOD-BOOSTING BACTERIA FOUND IN DIRT by Lylah Alphonse in Yahoo Shine (January, 2012)

Even if you don’t love gardening, digging in the dirt may be good for your health — and it has nothing to do with a love of nature or the wonder of watching things grow. The secret may be in the dirt itself: A bacteria calledMycobacterium vaccae that acts like anantidepressant once it gets into your system.

That’s right. A living organism that acts like a mood-booster on the human brain, increasing serotonin and norepinephrine levels and making people feel happier. It was accidentally discovered about 10 years ago, when Dr. Mary O’Brien, an oncologist at the Royal Marsden Hospital in London, tried an experimental treatment for lung cancer. She inoculated patients with killed M. vaccae, expecting the bacteria — which is related to ones that cause tuberculosis and leprosy — to boost their immune system. It did that, The Economist reported in 2007, but it also improved her patients’ “emotional health, vitality, and general cognitive function.” Later experiments with mice confirmed the bacteria’s effects; the study was published in a 2007 edition of the journal “Neuroscience.”

“These studies help us understand how the body communicates with the brain and why a healthy immune system is important for maintaining mental health,” the mouse study’s lead author, neuroscientist Dr. Christopher Lowry, said. “They also leave us wondering if we shouldn’t all be spending more time playing in the dirt.”

“We believe that prolonged exposure to [M.vaccae] from childhood could have a beneficial effect,” he added.

It raises the intriguing idea of a future where doctors could treat clinical depression or Seasonal Affective Disorder with a simple vaccine (and possibly a future in which kids don’t need quite so may baths). In the meantime, people seeking a bit of a boost may be able to find it in their own backyards.

In an article in The Atlantic this week, author Pagan Kennedy tests out the ultimate in eco-friendly antidepressants herself. “As I huff the soil, I have no way of knowing exactly how much M. vaccae is floating into my lungs — or whether it’s enough to change my mind,” she writes. “But I sure can smell this compost.”

We wouldn’t recommend inhaling dirt, of course. But, come spring, we’re looking forward to spending more time getting dirty.

- – - – - – - – - -

Article #9

Fungi Discovered In The Amazon Will Eat Your Plastic

Polyurethane seemed like it couldn’t interact with the earth’s normal processes of breaking down and recycling material. That’s just because it hadn’t met the right mushroom yet.

The Amazon is home to more species than almost anywhere else on earth. One of them, carried home recently by a group from Yale University, appears to be quite happy eating plastic in airless landfills. The group of students, part of Yale’s annual Rainforest Expedition and Laboratory with molecular biochemistry professor Scott Strobel, ventured to the jungles of Ecuador. The mission was to allow “students to experience the scientific inquiry process in a comprehensive and creative way.” The group searched for plants, and then cultured the microorganisms within the plant tissue. As it turns out, they brought back a fungus new to science with a voracious appetite for a global waste problem: polyurethane.

The common plastic is used for everything from garden hoses to shoes and truck seats. Once it gets into the trash stream, it persists for generations. Anyone alive today is assured that their old garden hoses and other polyurethane trash will still be here to greet his or her great, great grandchildren. Unless something eats it.

The fungi, Pestalotiopsis microspora, is the first anyone has found to survive on a steady diet of polyurethane alone and–even more surprising–do this in an anaerobic (oxygen-free) environment that is close to the condition at the bottom of a landfill.

Student Pria Anand recorded the microbe’s remarkable behavior and Jonathan Russell isolated the enzymes that allow the organism to degrade plastic as its food source. The Yale team published their findings in the journal Applied and Environmental Microbiology late last year concluding the microbe is “a promising source of biodiversity from which to screen for metabolic properties useful for bioremediation.” In the future, our trash compactors may simply be giant fields of voracious fungi.

- – - – - – - – - -

Article #10

Study finds reason for Alaska yellow cedar die-offs

Alaska Dispatch | Feb 02, 2012

According to an announcement from the U.S. Forest Service’s Pacific Northwest Research Station, a new study indicates the main culprit in a mysterious decline in yellow cedar trees over the past 100 years in Southeast Alaska and adjacent parts of British Columbia. The decline has affected about 60 to 70 percent of trees in those areas.

The synthesis paper, published in the February issue of the journal BioScience, summarizes 30 years of research on the economically and culturally significant tree’s decline and suggests conservation strategies. It blames shallow roots susceptible to freezing plus changes in climate and shifting patterns of insulating snow accumulation as the main culprits. The authors advise that conservation and management efforts take those factors into account.

“The cause of tree death, called yellow-cedar decline, is now known to be a form of root freezing that occurs during cold weather in late winter and early spring, but only when snow is not present on the ground,” explains Pacific Northwest Research Station scientist Paul Hennon, co-lead of the paper. “When present, snow protects the fine, shallow roots from extreme soil temperatures. The shallow rooting of yellow-cedar, early spring growth, and its unique vulnerability to freezing injury also contribute to this problem.”

- – - – - – - – - -

Article #11

Ancient plants back to life after 30,000 frozen years

Richard BlackBy Richard BlackEnvironment correspondent, BBC News

Arctic ground squirrelThe success of the operation hinged on the habits of the Arctic ground squirrel

Scientists in Russia have grown plants from fruit stored away in permafrost by squirrels over 30,000 years ago.

The fruit was found in the banks of the Kolyma River in Siberia, a top site for people looking for mammoth bones.

The Institute of Cell Biophysics team raised plants of Silene stenophylla - of the campion family – from the fruit.

Writing in Proceedings of the National Academy of Sciences (PNAS), they note this is the oldest plant material by far to have been brought to life.

Prior to this, the record lay with date palm seeds stored for 2,000 years at Masada in Israel.

The leader of the research team, Professor David Gilichinsky, died a few days before his paper was published.

In it, he and his colleagues describe finding about 70 squirrel hibernation burrows in the river bank.

“All burrows were found at depths of 20-40m from the present day surface and located in layers containing bones of large mammals such as mammoth, woolly rhinoceros, bison, horse, deer, and other representatives of fauna from the age of mammoths, as well as plant remains,” they write.

“The presence of vertical ice wedges demonstrates that it has been continuously frozen and never thawed.

“Accordingly, the fossil burrows and their content have never been defrosted since burial and simultaneous freezing.”

The squirrels appear to have stashed their store in the coldest part of their burrow, which subsequently froze permanently, presumably due to a cooling of the local climate.

Sugar sweet

Back in the lab, near Moscow, the team’s attempts to germinate mature seeds failed.

Silene stenophyllaThe fruits grew into healthy plants, though subtly different from modern examples of the species

Eventually they found success using elements of the fruit itself, which they refer to as “placental tissue” and propagated in laboratory dishes.

“This is by far the most extraordinary example of extreme longevity for material from higher plants,” commented Robin Probert, head of conservation and technology at the UK’s Millennium Seed Bank.

“I’m not surprised that it’s been possible to find living material as old as this, and this is exactly where we would go looking, in permafrost and these fossilised rodent burrows with their caches of seeds.

“But it is a surprise to me that they’re finding viable material from this placental tissue rather than mature seeds.”

The Russian team’s theory is that the tissue cells are full of sucrose that would have formed food for the growing plants.

Sugars are preservatives; they are even being researched as a way of keeping vaccines fresh in the hot climates of Africa without the need for refrigeration.

So it may be that the sugar-rich cells were able to survive in a potentially viable state for so long.

Silene stenophylla still grows on the Siberian tundra; and when the researchers compared modern-day plants against their resurrected cousins, they found subtle differences in the shape of petals and the sex of flowers, for reasons that are not evident.

The scientists suggest in their PNAS paper that research of this kind can help in studies of evolution, and shed light on environmental conditions in past millennia.

But perhaps the most enticing suggestion is that it might be possible, using the same techniques, to raise plants that are now extinct – provided that Arctic ground squirrels or some other creatures secreted away the fruit and seeds.

“We’d predict that seeds would stay viable for thousands, possibly tens of thousands of years – I don’t think anyone would expect hundreds of thousands of years,” said Dr Probert.

“[So] there is an opportunity to resurrect flowering plants that have gone extinct in the same way that we talk about bringing mammoths back to life, the Jurassic Park kind of idea.”

- – - – - – - – - -

Article #12

From Lawn to Pond, a Guardian of Central Park

Damon Winter/The New York Times

Vials and beakers used for soil samples.

Published: February 21, 2012

On a recent morning inside a nondescript laboratory building in the middle of Central Park, Tina M. Nelson was watching for signs of trouble.

Damon Winter/The New York Times

Ms. Nelson, lab coordinator for Central Park’s natural environment, brews “compost tea” by steeping leaves and wood chips in a 100-gallon container.

Damon Winter/The New York Times

Steam rises from the wood-chip composting mound, part of Central Park’s extensive composting operation.

Damon Winter/The New York Times

Soil samples from across the city, which are used for reference.

Wearing a cobalt-blue lab coat, Ms. Nelson, who bears the unwieldy title of soil, water and ecology laboratory coordinator for Central Park, ground up a soil sample from the Conservatory Garden with a large mortar and pestle. She then used a 3.5-cubic-centimeter soil scoop to gently add a bit of the earth to a crucible before placing it into a kiln to burn off the organic matter. “We haven’t looked at this area for a little while,” she said.

Ms. Nelson is, quite simply, the diagnostician for every aspect of Central Park’s natural environment. She tests the soils to see if there is too much nitrogen here, too little potassium there, and also monitors the park’s bodies of water. Her intimate knowledge of the park’s 843 acres — whether there has been an outbreak of curly-leaf pondweed on the Harlem Meer, for instance, or a brown patch of grass at the Sheep Meadow — helps landscapers decide what steps to take to maintain their assigned zones.

The result, especially come springtime, is an environment that almost seems to glow, filled with pale pink blossoms playing off electric-green meadows.

“The conservancy’s maintenance of the park is so much more than mowing and raking,” said Douglas Blonsky, president of the Central Park Conservancy, the nonprofit group that manages the park for New York City. “To do it right means knowing the park at a very fundamental level.”

Much the way a sculptor uses a block of marble, the landscape architects Frederick Law Olmsted and Calvert Vaux carved groves and meadows, ponds and waterfalls, onto the surface that is Central Park. The conservancy, similarly, employs a range of tools to make those landscapes resplendent. While fertilizers are applied judiciously, the park’s landscapers in recent years have turned to more natural remedies.

One of the most widely used is Ms. Nelson’s “compost tea,” a rich concoction made by steeping composted leaves and wood chips drawn from “the Mount,” the park’s giant compost heap near Fifth Avenue and 103rd Street, in a 100-gallon container. “We add starches and sugars — I don’t want to give away the recipe — and heat it,” she said. “We brew it like a big, stinking pot of tea.”

The liquid is then diluted with 400 gallons of water and sprayed on the seven major lawns twice a year, as well as on flower gardens and newly planted trees.

On a recent day, wisps of steam rose from the top of the compost pile. Ms. Nelson is responsible for ensuring its health, too, and frequently sticks a thermometer, attached to a long pole, into its belly. “When it reaches 120 to 130 degrees, we need to turn it over,” she said.

Ms. Nelson, who holds a degree in wildlife and fisheries conservation from Louisiana State University, has run the park’s soil lab for five years. Hydrating herself with an occasional sip of water from a beaker, she moves soil samples through a process called segmented flow analysis, in which the respective amounts of nitrogen, potassium and phosphorous are determined.

“We’re looking for the levels of nutrients,” she said. “Our ideal range for phosphate is 40 to 60.”

She also keeps tabs on the park’s wildlife, trying, when it is possible, to fight nature with nature. In the summer, to combat aphid infestations along the park’s shorelines, she releases ladybugs purchased in gallon containers. The ladybugs eat the aphids, sap-sucking insects that are the bane of gardeners.

“It’s very effective,” Ms. Nelson said. “You see thousands and thousands of ladybugs flying away and covering your hands. It’s really fun.”

More challenging is the algae that can appear on the park’s half-dozen lakes and ponds, all of which are man-made. While the park’s landscapers avoid spreading fertilizer near shorelines, the water runoff from streets and sidewalks can overload lakes with nitrogen and phosphorous during heavy rains, leading to blooms of algae.

Two to three times a week, from March to September, Ms. Nelson tests the water in places like Turtle Pond, the Lake and Harlem Meer, measuring temperature, pH and dissolved oxygen levels.

The Harlem Meer, in particular, has struggled with filamentous algae, which resembles a green wooly mat and competes with plants for nutrients. Ms. Nelson periodically dispatches an algae harvester on the Meer. A small barge with pontoons, the harvester uses a conveyor belt to scoop up the algae. Once the algae was tamed, however, curly-leaf pondweed, an invasive perennial, moved in. “Nature abhors a vacuum,” Ms. Nelson said.

At Turtle Pond, she has gone out in waders to rake filamentous algae by hand. The Lake, at 72nd Street, has its own troubles, with an excess of blue-green algae. Still, Ms. Nelson is against treating the park’s bodies of water with chemicals. “Absolutely not,” she said. For now, she added, aerating lakes and ponds with sprinklers is the safest way to restore oxygen and increase the population of largemouth bass, yellow perch, catfish and sunfish.

Ms. Nelson’s detailed understanding of the park’s ecology can sometimes be burdensome. On weekends she likes to visit the park with friends: a favorite picnic spot is the Great Hill, near 106th Street on the west side. But downshifting to a more leisurely mode is not easy.

“If I see phragmites in a water body, or people feeding bread to ducks and geese, I think, ‘Oh, I should do something about that on Monday,’ ” she said. When ducks rely on humans for food, especially if it is non-nutritious bread, they can develop a disease called angel wing, she explained, and eventually lose their ability to fly.

“One of my friends says it’s like walking with an off-duty police officer,” she said. “I can’t stop looking.”

- – - – - – - – - -

Article #13

World’s Oldest Living Tree — 9550 Years Old — Discovered In Sweden

ScienceDaily (Apr. 16, 2008) — The world’s oldest recorded tree is a 9,550 year old spruce in the Dalarna province of Sweden. The spruce tree has shown to be a tenacious survivor that has endured by growing between erect trees and smaller bushes in pace with the dramatic climate changes over time.For many years the spruce tree has been regarded as a relative newcomer in the Swedish mountain region. “Our results have shown the complete opposite, that the spruce is one of the oldest known trees in the mountain range,” says Leif Kullman, Professor of Physical Geography at Umeå University.


A fascinating discovery was made under the crown of a spruce in Fulu Mountain in Dalarna. Scientists found four “generations” of spruce remains in the form of cones and wood produced from the highest grounds.

The discovery showed trees of 375, 5,660, 9,000 and 9,550 years old and everything displayed clear signs that they have the same genetic makeup as the trees above them. Since spruce trees can multiply with root penetrating braches, they can produce exact copies, or clones.

The tree now growing above the finding place and the wood pieces dating 9,550 years have the same genetic material. The actual has been tested by carbon-14 dating at a laboratory in Miami, Florida, USA.

Previously, pine trees in North America have been cited as the oldest at 4,000 to 5,000 years old.

In the Swedish mountains, from Lapland in the North to Dalarna in the South, scientists have found a cluster of around 20 spruces that are over 8,000 years old.

Although summers have been colder over the past 10,000 years, these trees have survived harsh weather conditions due to their ability to push out another trunk as the other one died. “The average increase in temperature during the summers over the past hundred years has risen one degree in the mountain areas,” explains Leif Kullman.

Therefore, we can now see that these spruces have begun to straighten themselves out. There is also evidence that spruces are the species that can best give us insight about climate change.

The ability of spruces to survive harsh conditions also presents other questions for researchers.

Have the spruces actually migrated here during the Ice Age as seeds from the east 1,000 kilometres over the inland ice that that then covered Scandinavia? Do they really originate from the east, as taught in schools? “My research indicates that spruces have spent winters in places west or southwest of Norway where the climate was not as harsh in order to later quickly spread northerly along the ice-free coastal strip,” says Leif Kullman.

“In some way they have also successfully found their way to the Swedish mountains.”

- – - – - – - – - -

Article #14


March 16, 2012


Acorns (photo by Lori Quillen)
larger image


White-footed mouse (photo by Rick Ostfeld)
larger image

Lyme Disease Surge Predicted for the Northeastern U.S.

Boom-and-bust acorn crops and a decline in mice leave humans vulnerable to infected ticks

Millbrook, NY – The northeastern U.S. should prepare for a surge in Lyme disease this spring. And we can blame fluctuations in acorns and mouse populations, not the mild winter. So reports Dr. Richard S. Ostfeld, a disease ecologist at the Cary Institute of Ecosystem Studies in Millbrook, NY.

What do acorns have to do with illness? Acorn crops vary from year-to-year, with boom-and-bust cycles influencing the winter survival and breeding success of white-footed mice. These small mammals pack a one-two punch: they are preferred hosts for black-legged ticks and they are very effective at transmitting Borrelia burgdorferi, the bacterium that causes Lyme disease.

“We had a boom in acorns, followed by a boom in mice. And now, on the heels of one of the smallest acorn crops we’ve ever seen, the mouse population is crashing,” Ostfeld explains. Adding, “This spring, there will be a lot of Borrelia burgdorferi-infected black-legged ticks in our forests looking for a blood meal. And instead of finding a white-footed mouse, they are going to find other mammals—like us.”

For more than two decades, Ostfeld, Cary Institute forest ecologist Dr. Charles D. Canham, and their research team have been investigating connections among acorn abundance, white-footed mice, black-legged ticks, and Lyme disease. In 2010, acorn crops were the heaviest recorded at their Millbrook-based research site. And in 2011, mouse populations followed suit, peaking in the summer months. The scarcity of acorns in the fall of 2011 set up a perfect storm for human Lyme disease risk.

Black-legged ticks take three bloodmeals—as larvae, as nymphs, and as adults. Larval ticks that fed on 2011’s booming mouse population will soon be in need of a nymphal meal. These tiny ticks—as small as poppy seeds—are very effective at transmitting Lyme to people. The last time Ostfeld’s research site experienced a heavy acorn crop (2006) followed by a sparse acorn crop (2007), nymphal black-legged ticks reached a 20-year high.

The May-July nymph season will be dangerous, and Ostfeld urges people to be aware when outdoors.  Unlike white-footed mice, who can be infected with Lyme with minimal cost, the disease is debilitating to humans. Left undiagnosed, it can cause chronic fatigue, joint pain, and neurological problems. It is the most prevalent vector-borne illness in the U.S., with the majority of cases occurring in the Northeast.

Ostfeld says that mild winter weather does not cause a rise in tick populations, although it can change tick behavior.  Adult ticks, which are slightly larger than a sesame seed, are normally dormant in winter but can seek a host whenever temperatures rise several degrees above freezing.  The warm winter of 2011-2012 induced earlier than normal activity.  While adult ticks can transmit Lyme, they are responsible for a small fraction of tick-borne disease, with spring-summer nymphs posing more of a human health threat.

Past research by Ostfeld and colleagues has highlighted the role that intact forest habitat and animal diversity play in buffering Lyme disease risks. He is currently working with health departments in impacted areas to educate citizens and physicians about the impending surge in Lyme disease.

- – - – - – - – - -

Article #15

American Chestnut Returns to New York City

ScienceDaily (Apr. 12, 2012) — The once-mighty American chestnut tree, which was virtually wiped out by a pathogenic fungus that arrived in New York City more than 100 years ago, will return April 18 to the area where it was first discovered in the Bronx.

Researchers from the SUNY College of Environmental Science and Forestry (ESF) in Syracuse, N.Y., with supporters from The American Chestnut Foundation, will plant 10 transgenic American chestnut trees at a test site in The New York Botanical Garden. The scientists say there is reason to believe this field trial will reveal a variety of American chestnut that can survive a blight attack.

“We’ve been working on this for a long time and are looking at many genes. One particular gene has become my favorite,” said Dr. William Powell, a plant biotechnology expert at ESF. “And over the years it has convinced me that this gene is going to do the trick.”

Powell and his colleague, Dr. Charles Maynard, a tree improvement specialist, are enthusiastic about a gene derived from wheat that they have shown to increase resistance to a fungal pathogen in hybrid poplar. Powell and Maynard believe this gene will also be effective in the American chestnut because it detoxifies the oxalic acid produced by the blight pathogen. Oxalic acid kills the trees by attacking the cambium, the part of the tree that allows it to continue reproducing cells. A canker forms and everything above the canker dies. The roots can remain healthy and continue to send up shoots but the trees die back to ground level within a few years.

“If we can eliminate the oxalic acid, we probably will get a resistant tree,” Powell said.

The American chestnut was once a dominant species in the forests of the eastern United States; it accounted for 25 percent of the trees in the forest. A healthy one can grow more than 100 feet tall and measure 10 feet in diameter.

“This was a key species in the eastern forest. It was super at producing nuts for wildlife; very important for agriculture for human consumption of the nuts; very important for the lumber industry, making a rot-resistant, fast-growing wood product; and it was an important part of our history,” Powell said. “We really want to bring it back. The only way it can come back is to make a resistant tree because no one has been able to control the blight any other way.”

The location of the planting is significant.

“We’re very excited to be going back to The New York Botanical Garden because that’s a stone’s throw, literally across the street, from where the blight was discovered in 1904,” Maynard said.

Author Eric W. Sanderson, in his 2009 book, “Mannahatta: A Natural History of New York City,” wrote that when Henry Hudson first saw the island now called Manhattan in 1609, the American chestnut was “king of kings,” making up more than half the trees in the forest.

Powell and Maynard, who describe themselves as the third generation of scientists searching for a solution, have conducted their research through the American Chestnut Research and Restoration Program at ESF, with support from the New York chapter of The American Chestnut Foundation, the Forest Health Initiative, ArborGen and many others. They were the first research team to run field trials of transgenic varieties.

The trees being planted at the Botanical Garden are among more than 100 varieties of transgenic American chestnuts that are being tested in field trials or waiting to be tested for blight resistance. The planting is one of several events April 18 that will celebrate the progress made during the 25 years that Maynard and Powell have devoted to the effort.

Before the planting, the two scientists will present a 3 p.m. lecture on the economic and ecological importance of the American chestnut tree, their research progress and the trees that are about to be planted. After the trees are planted, the events will conclude with an ESF Alumni reception and dinner in the Lillian and Amy Goldman Stone Mill on the Bronx River and adjacent to the native Forest in the heart of the Garden.

- – - – - – - – - -

Article #16

Surprisingly complex community discovered in the mid-Devonian fossil forest at Gilboa

  • The origin of trees by the mid-Devonian epoch (398–385 million years ago) signals a major change in terrestrial ecosystems with potential long-term consequences including increased weathering, drop in atmospheric CO2, modified climate, changes in sedimentation patterns and mass extinction12,3. However, little is known about the ecology of early forests or how changes in early terrestrial ecosystems influenced global processes. One of the most famous palaeontological records for this time is the ‘oldest fossil forest’ at Riverside Quarry, Gilboa, New York, USA, discovered in the 1920s45. Hundreds of large Eospermatopteris sandstone casts, now thought to represent the bases of standing cladoxylopsid trees6, were recovered from a horizon that was originally interpreted as a muddy swamp. After quarry operations ceased, relatively minor outcrops of similar fossils at nearby localities have provided limited opportunities to evaluate this pervasive view using modern methods78. In 2010, removal of the quarry backfill enabled reappraisal of the palaeoecology of this important site. Here we describe a 1,200?m2 map showing numerous Eospermatopteris root systems in life position within a mixed-age stand of trees. Unexpectedly, large woody rhizomes with adventitious roots and aerial branch systems identified as aneurophytalean progymnosperms run between, and probably climb into, Eospermatopteris trees. We describe the overall habit for these surprisingly large aneurophytaleans, the earliest fossil group having wood produced by a bifacial vascular cambium. The site also provides evidence for arborescence within lycopsids, extending the North American range for trees in this ecologically critical group. The rooting horizon is a dark grey sandy mudstone showing limited root penetration. Although clearly belonging to a wetland coastal plain environment9, the forest was probably limited in duration and subject to periodic disturbance. These observations provide fundamental clarification of the palaeoecology of this mixed-group early forest, with important implications for interpreting coeval assemblage data worldwide.
- – - – - – - – - -
Article #17

An Underground Fossil Forest Offers Clues on Climate Change

Scott D. Elrick

SUBTERRANEAN William A. DiMichele in the Springfield Coal. The dark mass is a coal seam; the lighter shale above is interrupted by a fossil tree stump.

Published: April 30, 2012
Scientists are exploring dripping passages by the light of headlamps, mapping out an ecosystem from 307 million years ago, just before the world’s first great forests were wiped out by global warming. This vast prehistoric landscape may shed new light on climate change today.

Dating from the Pennsylvanian period of the Carboniferous era, the forest lies entombed in a series of eight active mines. They burrow through the rich seams of the Springfield Coal, a nationally important energy resource that underlies much of Illinois and two neighboring states and has been heavily mined for decades.

Pushed downward over the ages by the crushing weight of rock layers higher up, the Springfield forest lies at varying depths, 250 to 800 feet underground. The researchers have only sampled it so far, in the vicinity of Galatia, Illinois, but they think it extends more than 100 miles in one direction; its width has not been ascertained. An earlier discovery by the same team, the Herrin Coal forest farther north in Illinois, is just two miles long.

“Effectively you’ve got a lost world,” said Howard Falcon-Lang, a paleontologist at Royal Holloway, University of London, who has explored the site. “It’s the closest thing you’ll find to time travel,” he added.

Curiously, the forest can be viewed only from below. The scientists crane their necks, illuminating the ceiling with miners’ helmet lamps. Hundreds of millions of years ago, trees and other plants grew atop thick peat that eventually compressed into coal; when that was excavated, the forest’s fossilized remains could be seen in the mine’s shale ceiling.

“It’s a botanical Pompeii, buried in a geological instant,” said William A. DiMichele, a paleobiologist and curator of fossil plants at the Smithsonian Institution in Washington and one of the forest’s discoverers. He believes it was gently entombed by floods that successively washed through a swamp.

A river as wide as the Mississippi snaked through the fossil-forest landscape; its course is still clearly visible. As the climate grew drier with rising temperatures in the late Carboniferous period, rainfall became seasonal and pounded sediment out of the soil, filling the river with silt. This suffocated the forest as the river spilled over its banks.

The flooding was incremental and gradual, hardly ruffling the fern leaves that it entombed in mud and that can be seen, down to the smallest frond, on the ceilings of the coal mines.

Huge fossilized trees still stand rooted in their original but compacted soil, surrounded by the litter of leaves that once fluttered down.

Primitive, lizardlike reptiles were then evolving in the swamps, but there are almost no animal fossils in the Springfield forest — save for the occasional cockroach wing — since such creatures easily fled the rising waters.

Such snapshots of the very distant past — tens of millions of years before the age of dinosaurs — are hard to come by. “It is extraordinarily rare to get fossil forests of any extent at all,” said Kirk Johnson, a paleobotanist at the Denver Museum of Nature and Science. “It’s usually just a few trees here and there. But here is an ancient geography — effectively unheard of.”

Dr. DiMichele and colleagues have explored a five-mile path, or transect, starting at the ancient riverbank and arrowing through the swamp. Just as if this were a living forest, they have stopped along the route to identify individual leaves or study fallen trunks. Moving away from the river, a dense thicket of seed ferns gives way to tree ferns and low ground cover. Farther out, tree ferns are dwarfed by forest giants called scale trees.

“It was a Dr. Seuss world,” Dr. Johnson said of the scale-tree forests: sun-washed quagmires studded with giant green stalks like asparagus spears, hundreds of feet tall. (Scale trees did not unfurl spreading crowns until the very end of their life cycle.) Dr. DiMichele has followed a fallen scale tree for 100 feet, before it disappeared behind coal not yet mined away. Six feet wide at the base, it was hardly any narrower at that great height.

Scale trees had reptilian-looking, photosynthetic bark that coal miners sometimes mistake for dinosaur remains. Tube-shaped with spongy pulp inside, the trees snapped in two when storms ravaged the swamp. Immense, cylindrical roots kept stumps firmly upright, as seen in the mines.

By coincidence, the earliest ancestor of these scale trees has just been discovered in a fossil forest in New York State. Repairs at Gilboa Dam, north of the Catskills, uncovered the floor of what may be the world’s oldest forest, scientists reported last month in the journal Nature. Dating from the Devonian Period, it is 78 million years older than the Springfield find, but the mapped remains are much smaller, covering about a third of an acre.

There were no birds in the Pennsylvanian period, so insects flourished in the oxygen-rich air. Hiking through the Springfield forest would have meant dodging millipedes six feet long and dragonflies the size of crows.

And yet the fossil leaves show much less chewing by insects than the vegetation in our modern backyards. Animals had barely evolved herbivory, the habit of eating live plants, and instead subsisted on putrefying remains in the fetid swamp.

Two million years later — a geological eye blink — came vast extinctions of plants, wiping out many of the species found in the Springfield forest. The mighty scale trees all died off. Their modern relatives are quillworts, just six inches high.

The reach of the Springfield forest should allow scientists to undertake ecosystem-wide analyses in a way never before possible in landscapes so ancient, and such studies may help them predict the effects of global warming today.

“With our own CO2 rises and changes in climate,” said Scott D. Elrick, a team member from the Illinois State Geological Survey, “we can look at the past here and say, ‘It’s happened before.’ ”

Today, we burn the scale trees of the Carboniferous by the billions: they have all turned to coal. Newly discovered, the Springfield forest is already crumbling to bits, as coal-mine ceilings quickly do after exposure. But with continued mining, more ceilings are being revealed every day.

“You have to dig to find fossils, going inside the anatomy of the planet,” Dr. Johnson said. “Bill DiMichele realizes he has an entire industry digging for him, creating a tunnel into an ancient world.”

- – - – - – - – - -

 Article #18

Debut of the First Practical ‘Artificial Leaf’

ScienceDaily (Mar. 27, 2011) — Scientists have claimed one of the milestones in the drive for sustainable energy — development of the first practical artificial leaf. Speaking in Anaheim, California at the 241st National Meeting of the American Chemical Society, they described an advanced solar cell the size of a poker card that mimics the process, called photosynthesis, that green plants use to convert sunlight and water into energy.

“A practical artificial leaf has been one of the Holy Grails of science for decades,” said Daniel Nocera, Ph.D., who led the research team. “We believe we have done it. The artificial leaf shows particular promise as an inexpensive source of electricity for homes of the poor in developing countries. Our goal is to make each home its own power station,” he said. “One can envision villages in India and Africa not long from now purchasing an affordable basic power system based on this technology.”

The device bears no resemblance to Mother Nature’s counterparts on oaks, maples and other green plants, which scientists have used as the model for their efforts to develop this new genre of solar cells. About the shape of a poker card but thinner, the device is fashioned from silicon, electronics and catalysts, substances that accelerate chemical reactions that otherwise would not occur, or would run slowly. Placed in a single gallon of water in a bright sunlight, the device could produce enough electricity to supply a house in a developing country with electricity for a day, Nocera said. It does so by splitting water into its two components, hydrogen and oxygen.

The hydrogen and oxygen gases would be stored in a fuel cell, which uses those two materials to produce electricity, located either on top of the house or beside it.

Nocera, who is with the Massachusetts Institute of Technology, points out that the “artificial leaf” is not a new concept. The first artificial leaf was developed more than a decade ago by John Turner of the U.S. National Renewable Energy Laboratory in Boulder, Colorado. Although highly efficient at carrying out photosynthesis, Turner’s device was impractical for wider use, as it was composed of rare, expensive metals and was highly unstable — with a lifespan of barely one day.

Nocera’s new leaf overcomes these problems. It is made of inexpensive materials that are widely available, works under simple conditions and is highly stable. In laboratory studies, he showed that an artificial leaf prototype could operate continuously for at least 45 hours without a drop in activity.

The key to this breakthrough is Nocera’s recent discovery of several powerful new, inexpensive catalysts, made of nickel and cobalt, that are capable of efficiently splitting water into its two components, hydrogen and oxygen, under simple conditions. Right now, Nocera’s leaf is about 10 times more efficient at carrying out photosynthesis than a natural leaf. However, he is optimistic that he can boost the efficiency of the artificial leaf much higher in the future.

“Nature is powered by photosynthesis, and I think that the future world will be powered by photosynthesis as well in the form of this artificial leaf,” said Nocera, a chemist at Massachusetts Institute of Technology in Cambridge, Mass.

Nocera acknowledges funding from The National Science Foundation and Chesonis Family Foundation.

- – - – - – - – - -

Article #19

3 New Studies Link Bee Decline to Bayer Pesticide

—By Tom Philpott

| Thu Mar. 29, 2012 5:40 PM PDT

It’s springtime, and farmers throughout the Midwest and South are preparing to plant corn—and lots of it. The USDA projects this year’s corn crop will cover 94 million acres, the most in 68 years. (By comparison, the state of California occupies a land mass of about 101 million acres.) Nearly all of that immense stand of corn will be planted with seeds treated with neonicotinoid pesticides produced by the German chemical giant Bayer.

And that may be very bad news for honey bees, which remain in a dire state of health, riddled by large annual die-offs that have become known as “colony collapse disorder” (CCD).

In the past months, three separate studies—two of them just out in the prestigious journalScience—have added to a substantial body of literature linking widespread use of neonicotinoids to CCD. The latest research will renew pressure on the EPA to reconsider its registration of Bayer’s products. The EPA green-lighted Bayer’s products based largely on a study funded by the chemical giant itself—which was later discredited by the EPA’s own scientists, as this leaked memo shows.

When seeds are treated with neonics, the pesticides get absorbed by the plant’s vascular system and then “expressed” in the pollen and nectar, where they attack the nervous systems of insects. Bayer targeted its treatments at the most prolific US crop—corn—and since the late 1990s, corn farmers have been blanketing millions of acres of farmland with neonic-treated seeds.

And it’s not just corn. In addition to the vast corn crop mentioned above, Bayer’s neonics have worked their way into substantial portions of the soy, wheat, cotton, sorghum, and peanut seed markets. In 2010, according to research by the Pesticide Action Network of North America, at least 142 million total acres were planted in neonic-treated seeds—a trend that will continue if not increase in  the 2012 growing season. That represents a landmass equal to the footprints of California and Washington State.

But even that’s not all. As I showed in this January post, Bayer’s neonics are also common in home-garden and landscaping products.

The ubiquitous pesticides appear to affect bees in two ways: in big lethal doses that occur at the time of seed planting, when neonic-infused dust wafts around in growing areas; and in tiny doses that happen when bees bring neonic-infused pollen into hives, which don’t kill them immediately but appears to damage their immune systems and homing abilities.

Here’s a quick snapshot of the new research.

• In a paper forthcoming in the peer-reviewed and highly respected journal Science—released Thursday on (subscription-required) ScienceExpress—researchers found that exposure to small, sublethal doses of a neonic called thiamethoxam significantly affects bees’ ability to find their way back to their hives—”at levels that could put a colony at risk of collapse.” The research team also found that previous impact studies “are likely to severely underestimate sublethal pesticide effects when they are conducted on honey bee colonies placed in the immediate proximity of treated crops.”

• The other forthcoming Science paper—also behind a paywall on ScienceExpress—looked at neonics’ effect on wild bumblebees, which are another critical pollinator that have gone intosevere decline in recent years. In this study, researchers subjected bumblebee colonies to “field-realistic levels of the neonicotinoid imidacloprid” and then “allowed them to develop naturally under field conditions.” The result: “Treated colonies had a significantly reduced growth rate and suffered an 85% reduction in production of new queens.” Their conclusion: “Given the scale of use of neonicotinoids, we suggest that they may be having a considerable negative impact on wild bumble bee populations across the developed world.”

• The third recent study, published in the American Chemical Society’s Environmental Science & Technology journal, looked at what happens to bees when farmers plant treated seeds, when foraging bees are exposed to neonic-containing dust. The authors found “lethal effects compatible with colony losses phenomena observed by beekeepers.”

The latest burst of research follows on the heels of a study released in January by Purdue researchers (I summarized their results here). They determined that bees are exposed to “extremely high” levels of Bayer’s clothianidin in the fumes that rise up when farmers plant corn seed in the spring. They found the pesticide in dead bees “collected near hive entrances during the spring sampling period,” as well as in “pollen collected by bees and stored in the hive.”

These studies, combined with what we know of the the tortured, Bayer-influenced nature of neonics’ march through the regulatory process, paint a damning picture. As Pesticide Action Network’s Heather Pilatic put it on Huffington Post, “Wild pollinators and honeybees alike have been facing an increasingly toxic landscape since the introduction and rapid uptake of neonicotinoids in the late 1990s…these pesticides are prevalent, persistent, and more scientists confirm everyday that they are making bees sick (or dead) through a number of different mechanisms and routes of exposure.”

This accumulation of disturbing science raises a vital question: Does the Obama EPA have the backbone to take on the agrochemical industry during an election year and ban Bayer’s lucrative chemicals? The long-term status of the United States as a healthy habitat for bees, wild and cultivated alike, may hinge on the answer.

- – - – - – - – - -

Article #20

Scientists use Thoreau’s journal notes to track climate change

Researchers use Walden author’s tables of flowering dates in 1840s Massachusetts to show temperature has risen 2.4C

Walden Pond near Boston, Massachusetts, close to where Henry David Thoreau lived

Green grass of home … Walden Pond, Massachusetts, close to where Henry David Thoreau lived in a cabin as part of a two-year experiment. Photo: Joseph Sohm/Corbis

Fittingly for a man seen as the first environmentalist, Henry David Thoreau, who described his isolated life in 1840s Massachusetts in the classic of American literature Walden, is now helping scientists pin down the impacts of climate change.

The American author, who died in 1862, is best known for his account of the two years he spent living in a one-room wooden cabin near Walden Pond “because I wished to live deliberately, to front only the essential facts of life”. Packed with descriptions of the natural world he loved, Walden is partly autobiographical, partly a manifesto for Thoreau’s belief in the rightness of living close to nature. “I never found the companion that was so companionable as solitude,” he writes. “Simplify, simplify.”

But Thoreau was also a naturalist, and he meticulously observed the first flowering dates for over 500 species of wildflowers in Concord, Massachusetts, between 1851 and 1858, recording them in a set of tables. When Richard Primack, a biology professor at Boston University, and fellow researcher Abraham Miller-Rushing discovered Thoreau’s unpublished records, they immediately realised how useful they would be for pinning down the impact of the changing climate over the last century and a half. The timing of seasonal events such as flowering dates is known as phenology, and the phenologies of plants in a temperate climate such as that of Massachusetts are very sensitive to temperature, say the scientists. Studying phenology is therefore a good indicator of ecological responses toclimate change.

“We had been searching for historical records for about six months when we learned about Thoreau’s plant observations. We knew right away that they would be incredibly useful for climate change research because they were from 150 years ago, there were so many species included, and they were gathered by Thoreau, who is so famous in theUnited States for his book Walden,” said Primack. “The records were surprisingly easy to locate once we were aware of them. A copy was given to us by an independent research scholar, who knew that they would be valuable for climate change research.”

After deciphering Thoreau’s “notoriously bad” handwriting, and spending “a large amount of time” matching the names used for plants in the 1850s with their modern equivalents, Primack and Miller-Rushing compared Thoreau’s data on flowering dates, coupled with research from the 19th-century local botanist Alfred Hosmer, with modern data of their own. Looking at 43 common Concord plant species, they found “unambiguously” that these plants, on average, “are now flowering 10 days earlier than they were in Thoreau’s time”, they write in an article for the journal BioScience.

Over the 155 intervening years, the average temperature in Concord increased by 2.4C, they estimate.

Primack and Miller-Rushing also searched for hundreds of the plant species mentioned by Thoreau, working with local botanists and naturalists to track them down. After three years of fieldwork, they were forced to recognise that many of the species observed by the Walden author in the 1850s were either no longer present in Concord or very hard to find. They concluded that 27% of the species recorded by Thoreau and other botanists were no longer present in Concord at all, and a further 36% of formerly common species were now rare. “Thoreau was a keen observer of nature and a dedicated journalist,” said Primack. “I am confident that he would have recognised the changing patterns of the timing of natural events in Concord. Thoreau was also an activist, and perhaps he would also be involved in the movement to reduce the greenhouse gases that are linked to climate change.”

The Walden author will be involved further, at least obliquely: Primack and Miller-Rushing have now discovered that Thoreau also made detailed observations on the “leaf-out” dates of trees in Concord in the 1850s, and say it is clear already that trees in Concord are “leafing out” earlier than they did in Thoreau’s time. They are now planning more research in this area, guided by Thoreau’s notes from a century and a half ago.

- – - – - – - – - – - – - – - -