#Trees Have Internal Clocks Too, Study Finds Like human bodies some trees have internal clocks that coordinate the activities of their cells with the cycles of day
and night a new study finds. Scientists knew of these circadian rhythms in leaves but the new study is the first to demonstrate them in whole trees.
In the study the researchers looked at the Tasmanian blue gum tree and found it appears to use its internal clock to regulate its intake of water.
These cycles could affect models of climate change the scientists say. It had never been shown that the circadian rhythm of the leaf affected the whole tree said study researcher Rubã n DÃ az Sierra a physicist at the National University of Distance Education in Spain.
If it works for the tree it works for the whole forest he added. DÃ az Sierra's colleagues monitored trees in special whole-tree chambers as part of the Hawkesbury Forest Experiment near Sydney Australia a broader experiment to study how Australia's eucalypt
forests will respond to changes in atmospheric carbon dioxide and climate. These chambers enable researchers to control the air temperature humidity
and amount of light the trees are exposed to although these parameters were allowed to vary in this study.
Nature's Giants: Tallest Trees On earth The researchers measured how much water vapor they lost through small openings in the their leaves called stomata.
The scientists compared these values during overcast nights when the environment stays mostly constant throughout the evening with nights that saw dramatic changes in temperature and humidity.
Artificial neural networks machine-learning models inspired by the brain were used to determine just how much the circadian rhythms affected the opening of stomata and the trees'water use.
if the time of day affects trees'carbon-dioxide consumption it would alter models of how climate change will affect ecosystems.
Still DÃ az Sierra expects some resistance to the notion that whole trees display circadian rhythms.
But if it works on small plants on the leaves why not the whole tree?
If salvage companies get their way an underwater forest of 50000-year-old trees only recently discovered could be destroyed to make high-end coffee tables.
Pull up the trees for the valuable wood. You have to think of the cachet of something made from a 50000-year-old wood said Ben Raines the diver who first reported on the site and the executive director of the Weeks Bay Foundation a waterways conservation organization.
as long as they left the majestic trees intact. Primeval forest The grove of 50000-year-old bald cypress trees was preserved beneath ocean sediments off the coast of Alabama until Hurricane Katrina swept those sediments away.
The trees were in such pristine condition that fresh sap oozed from the stumps when they were cut.
The enchanted forest became a natural reef teeming with fish and crustaceans that sheltered between tree roots.
After Livescience's Ouramazingplanet originally reported the story people from around the country contacted Raines to discover the forest's location including several salvage companies hoping to mine the forest for its wood.
Scientists believe the grove of thousand-year-old trees could reveal millennia of the Gulf of mexico's climate history.
The outer portion of the trees could indeed be around for a while for divers to enjoy said Steven Leavitt a dendrochronologist (someone who studies tree rings) at the University of Arizona who is involved not in studying the forest.
Here underwater trees in the Great lakes may not be subject to shipworms zebra mussels are slowly eating through the wood.
and dating from tree rings impossible after several years he said. Still the fact that the forest has been around at least eight years
and found that tree cover correlates with human health because forest dwellers eat a more diverse diet than people in other environments do.
 In the North american West damage from fire logging and infection by the devastating mountain pine beetle is evident.
A windstorm in 2009 shows up as leveled trees in southwestern France. In southern Sweden an extratropical cyclone flattened forests in 2005.
which may provide tree cover but without the original ecosystems. The team also plans to continue to update the map annually
These phenomena such as the sight of a few trees viewed through a window may appear insignificant
a nature island with waterfalls rivers different kinds of trees flowers plants grass rocks a beach and dirt paths;
#Warm Water Under Antarctic Glacier Spurs Rapid Melting A two-month-long expedition to one of the most remote sites on the planet the sprawling Pine Island Glacier in Antarctica
An international team of researchers journeyed to the southernmost continent to study the Pine Island Glacier which is the longest and fastest-changing glacier on the West Antarctic Ice Sheet.
Since warm seawater flows beneath the ice shelf (the part of the glacier that floats on the ocean) scientists have known that the Pine Island Glacier was melting from below.
Intensive melting under the Pine Island ice shelf as observed in our study could potentially lead to the speed up
and without that restraining force the Pine Island catchment basin could further contribute to global sea-level rise.
Glacial plug The Pine Island Glacier currently acts as a plug that holds back the immense West Antarctic Ice Sheet whose melting ice contributes to rising sea levels.
As the Pine Island Glacier makes its seaward retreat it also develops and drops icebergs as part of a natural cycle.
In early July a huge iceberg measuring about 278 square miles (720 square kilometers) broke off from the Pine Island Glacier
Modeling melt To see how much the Pine Island Glacier was melting Holland and his colleagues installed sensors inside holes drilled 1640 feet (500 m) through the solid ice at various points across the glacier.
The data published online today (Sept. 12) in the journal Science will help scientists piece together how the Pine Island Glacier is changing
and more intense allergen production from a number of tree species that flower in the spring including oak birch olive
and loblolly pine though these findings can vary greatly by subspecies and location. Researchers have found for instance that some species of oak are producing pollen four weeks earlier than before.
At the same time warmer winters can lead some tree species to produce less pollen when they flower in the spring.
Later in the year summer brings allergens from weeds and grasses which can produce more allergens
This sudden boom in tree blossoms could have allergy sufferers seeing symptoms more abruptly than usual.
As per this time of year the tree pollen is the main allergy threat especially from the less conspicuous oak maple pine and elm varieties.
What seems to have awakened the trees was the sudden warmth early last week followed by drenching rain in many areas.
#Weird Forests Once Sprouted in Antarctica DENVER Strange forests with some features of today's tropical trees once grew in Antarctica new research finds.
The trees are the best way to figure this out because trees record physiological responses in their rings Ryberg told Livescience.
A forest mystery Fossilized wood and leaf impressions record a history of the Antarctic forests.
as if the trees had shed all at once a sign of a deciduous forest. To confirm this Ryberg
and her colleagues gathered samples of fossil wood and examined the tree rings. Wood cells in the rings reveal how the trees grew:
Early wood is produced when the tree is growing upward and outward. Late wood is produced when the tree is preparing to go dormant.
At that point the tree stops growing and starts storing carbon in its cells. Late wood is denser than early wood
and has thicker cell walls. Deciduous and evergreen trees have different patterns of late and early wood.
Ryberg and her colleagues examined the Antarctic fossils and found that they looked evergreen. Image Gallery:
Life at the South pole Now we have leaves that suggest a deciduous habit and fossil wood that is suggesting an evergreen habit
Tropical trees that are exposed not to seasons experience a sort of short-term dormancy that echoes what is seen in the Antarctic wood.
and replacing them with big swathes of palm tree monocultures threatening the future existence of orangutans said Lee Hannah a senior fellow in climate change biology at Conservation International a global group devoted to saving endangered
 The same is happening in Peru where forests are being cleared to make way for palm tree plantations said Clinton Jenkins a conservation scientist at North carolina State university.
Such palm trees are a rich source of palm oil which is used in food products and to make biofuels like biodiesel a fuel with growing demand as a source of cleaner energy.
which tree species filled the forests before they were cleared for fields and fuel. Swamp-loving plants like sedges and tussocks are the fossil survivors not delicate leaves from hardwood trees.
Now thanks to a rare fossil discovery in the Pennsylvania foothills scientists can tell the full story of America's lost forests.
The fossil site is a muddy layer packed with leaves from hardwood trees that lived more than 300 years ago along Conestoga Creek in Lancaster County Pa.
Before Europeans arrived American beech red oak and sweet birch trees shaded Conestoga Creek according to a study the researchers published today (Nov 13) in the journal PLOS ONE.
Some 300 years later those trees are gone. The same spot is now home to mostly box elder
and sugar maple trees said Sara Elliott the study's lead author and a research associate at the University of Texas at Austin's Bureau of Economic geology.
This is a very unusual opportunity to compare modern and fossil forest assemblages Elliott told Livescience.
It's like you're time traveling she said. Elliott carefully peeled apart hundreds of leaves stuck together by mud
Other kinds of trees found in the fossil layer that have vanished since from North america include the American chestnut
which was attacked by an imported fungal disease called the chestnut blight. Leaves from swamp plants also appear in the mud confirming that the forested spot was on the upslope edge of a nearby wetland.
The three dominant tree species found in the fossil forest leaves still exist today in the Northeast
The scientists hope that identifying similar fossil tree-leaf sites will help the massive milldam restoration projects underway throughout the Northeast.
when diatoms (a type of algae with hard cell walls made ofâ silica) settled on the lake bottom alternating with layers of clay and volcanic ash.
 We can analyze volcanic ash brought into the lake by wind using the technique of radiometric dating so it will be possible to measure how long ago each ash layer was deposited.
The ash bands may also help to align the core with others drilled at different locations
since ash from volcanic eruptions tends to settle over wide areas. Â Â The section of the core shown here (see the enlargement in the lower right of the image) also revealed where banded lake deposits have a well-defined contact on top of an ancient clay-rich soil.
Because trees and other plants absorb CO2 from the atmosphere they reduce our overall greenhouse gas emissions by roughly 14 percent.
Another problem with the term is that some so-called superfoods fall in and out of favor with dieticians such as coffee or eggs.
One could just as easily include green tea coffee dark chocolate yogurt and olives to the superfood list for a variety of reasons mentioned above.
and may likely extend throughout the evolutionary tree. Clint J Perry has received funding from the Endeavour Awards Fellowship in Sydney
A major relatively brief shift in plant life from grasses to trees occurred during this period as well.
On the other hand trees and shrubs that have adapted to cooler wetter conditions depend on a type of photosynthesis known as C3
Instead this discovery hints that an extinction of megafauna herbivores that normally browsed on C3 plants allowing trees and shrubs to rise in dominance.
10 Things You Didn't Know About Food These qualities have earned it the nickname custard apple
The paw paw tree (Asimina triloba) is indigenous to 26 states in the United states growing wild from the Gulf Coast up to the Great lakes region.
Paw paw aficionados eat the fruit straight from the tree or use it in a variety of delicious recipes.
If you're a do-it-yourselfer you can purchase your own pawpaw trees and start harvesting these fruits within a few years.
The coconut palm ranks as one of the most useful plants on the planet. For generations cultures in tropical regions have used it for food cosmetics or building materials.
The species Cocos nucifera is thought to be native to the coasts of Southeast asia and Melanesia. Scholars theorize the plant spread on ocean currents to India and East Africa.
Coconut palms may live as long as 100 years and grow to nearly 100 feet tall. At least 12 crops can come out of a coconut plant depending on its state of maturation.
#What Is Garcinia cambogia? The fruit Garcinia cambogia was once just the less popular cousin of a trendy fruit the mangosteen.
But now nutritional supplements containing Garcinia cambogia extract have become the rage touted for their purported ability to curb appetite
and stop weight gain. Â The gambooge fruit also known as the Malabar tamarind grows across southwest India Myanmar and Indonesia.
but trees are usually the first on the scene during spring allergy season says Jay M. Portnoy M d. president of the American College of Allergy Asthma and Immunology (ACAAI) and chief section of allergy
Rain can provide some initial relief by reducing tree pollen counts but it also can spur the growth of grass
A dry and cold winter followed by recent heavy rains has resulted in a slightly delayed onset of spring tree pollens said Paul Ratner M d. Medical Director of Sylvana Research in San antonio Texas
. The primary tree pollen Oak began appearing Mid-march and within a week extremely high pollen counts were recorded.
The tree pollen season is expected to last through early May. Heavy precipitation in many areas of the U s. is associated with a greater release of seasonal pollens according to Clifford W. Bassett M d. a fellow of the ACAAI
Trees began pollinating in early February and will continue through June overlapping with our grass season in May and June.
1. Trees produce pollen the dust-like male reproductive parts of plants that cause most allergies.
In some southern states trees can produce pollen as early as January while pollen production usually begins in April in the north.
The oak tree which is prevalent throughout the United states produces large quantities of pollen and is a major cause of allergies.
Cedar juniper cypress and sequoia trees have all been known to cause allergies and if you're allergic to one you may be allergic to them all.
Other suspects include elm trees which are common in the eastern and midwestern regions birch trees olive trees sycamores
and poplars including cottonwoods balsam and aspen. 2. Grasses usually come along to stir up allergy symptoms after trees are through pollinating typically from late spring to early summer.
Common culprits are timothy grass Bermuda grass sweet vernal red top and some blue grasses. 3. Weeds are guilty of causing most of the allergy misery that occurs in the late summer and early fall.
Top on the list of offenders is ragweed which affects as many as 75 percent of all hay fever sufferers.
Melatonin may also produce this side effect if taken with herbs that slow blood clotting such as angelica clove danshen garlic ginger ginkgo Panax ginseng red clover and willow.
Similarly melatonin will enhance herbs with sedative effects such as calamus California poppy catnip hops Jamaican dogwood kava St john's wort skullcap valerian and yerba mansa.
#What Is the Oldest Tree in the World? Until 2013 the oldest individual tree in the world was Methuselah a 4845-year-old Great Basin bristlecone pine (Pinus longaeva) in the White Mountains of California.
But then researchers announced the dating of a 5062-year-old P. longaeva which isalso in the White Mountains according to the Rocky mountain Tree-Ring Research group.
The tree has not yet been named. The next oldest tree on the list is a national monument in Iran:
The Zoroastrian Sarv (Sarv-e-Abarkooh) estimated to be about 4000 years old or older.
This Mediterranean cypress tree (Cupressus sempervirens) which is in Abarkuh Yazd Iran may well be the oldest living thing in Asia.
Living in a churchyard of the Llangernyw village in North Wales the Llangernyw Yew is estimated also to be at least 4000 yeas old.
The yew tree (Taxus baccata) is believed to have taken root sometime during Britain's Bronze age. And on the other side of the world in an Andes mountains grove in Chile we have a 3642-year-old Patagonian cypress (Fitzroya cupressoides.
The ancient specimen which is called sometimes the Alerce (alerce is a common Spanish name for F. cupressoides) is the third-oldest tree to have its exact age calculated.
Though these are the oldest individual trees in the world they are technically not the oldest living organisms.
There are several clonal colonies which are made up of genetically identical trees connected by a single root system that are much older.
For example the Pando or trembling giant is a clonal colony of quaking aspen (Populus tremuloides) estimated to be an astounding 80000 years old.
It is located in Fishlake National Forest in south-central Utah. Follow Livescience on Twitter@livescience. We're also on Facebook & Google+o
#What Is the Paleo Diet? The Paleo Diet also known as the Stone age Caveman or Ancient Diet is a modern attempt to replicate the diet of humans of the Paleolithic age.
#What Is the World's Largest Tree? The largest tree in the world is a giant sequoia (Sequoiadendron giganteum) in California's Sequoia National park. Called General Sherman the tree is about 52500 cubic feet (1487 cubic meters) in volume.
That's the equivalent of more than half the volume of an Olympic-size swimming pool commonly considered to be 88500 cubic feet (2506 cubic meters.
That makes it only a middle-age giant sequoia as other trees are believed to be more than 3220 years old based on tree ring counts.
The tree lost a huge branch in 2006 which shattered a new walkway and fence below.
It didn't affect General Sherman's ranking as the largest tree however as that was calculated using trunk volume and not branches.
but that doesn't put it anywhere close to the record of tallest tree. The honor of tallest tree in the world is bestowed upon Hyperion a 379.7-foot-tall (115.7 m) redwood also located in California.
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#What Is the World's Tallest Tree? The tallest trees in the world are redwoods (Sequoia sempervirens)
which tower above the ground in California. These trees can easily reach heights of 300 feet (91 meters.
Among the redwoods a tree named Hyperion dwarfs them All the tree was discovered in 2006 and is 379.7 feet (115.7 m) tall.
Shortly after it was measured and deemed the world's tallest a writer for the New yorker climbed close to the top
and described what it was like to stand there. A wind had begun to blow and the top of Hyperion swayed back and forth wrote Richard Preston.
Other giant redwoods include Helios which is just a shade smaller than Hyperion at 374.3 feet (114.1 m) as well as Icarus (371.2 feet
A typical redwood lives for 500 to 700 years although some have been documented at more than 2000 years old.
The National park service says the redwoods'great height is due in part to the favorable climatic conditions found in California including mild year-round temperatures and heavy annual rainfall.
#What's the Best Way to Keep Your Christmas tree Fresh? Holiday Science Project Every year about 25 million Christmas trees are purchased in the United states according to the National Christmas tree Association.
Keeping it fresh is very important not only for preserving its beauty but also to prevent it from becoming a fire hazard.
With proper care a Christmas tree can stay fresh for a month or even longer. Everyone knows that you must add water to the reservoir in the base of a Christmas tree
and as a rule of thumb a typical tree absorbs a quart of water for each inch of its diameter.
Will adding other household products to the water help keep them fresher longer? There is some debate about
whether adding any kind of mixture to the water helps keep a tree fresher longer. Tchukki Anderson a staff arborist for the Tree Care Industry Association says many people have had success by mixing a tablespoon of sugar or corn syrup in the water.
However she says water is usually enough. A recent study at the University of Wisconsin-Stevens Point confirmed that keeping fresh-cut trees watered will reduce needle loss refuting claims that watering a dead tree is pointless.
However the study's author tree scientist Les Werner says additives such as sugar aspirin or even vodka don't help.
Clean water still works the best. But don't take their word for it. Try the experiment
and find out for yourself how to keep your Christmas tree fresher longer. If your family uses a real Christmas tree
or fresh evergreens for decoration borrow a few small cut branches and try this experiment. You could also try using cut flowers such as carnations.
In 1912 Japan gave more than 3000 cherry-blossom trees to the United states as a gift to honor the growing bond between the two countries.
Now the annual National Cherry Blossom Festival in Washington D c. commemorates this century-old offering of goodwill when the trees bloom each spring.
The flowering trees in Washington D c. symbolize friendship between nations the renewal of spring and the ephemeral nature of life according to the U s. National park service.
Similar to Washington D c. Japan has a yearly flower-viewing celebration called hanami where thousands of people hold feasts under blooming cherry-blossom trees or sakura.
The cherry-blossom tree is known for its short but brilliant blooming season a natural process that metaphorically describes human life.
This means that in a single city different cherry trees will flower at different times. Those that are downtown tend to flower earlier than suburban trees there's more pavement downtown
which creates an urban island heating effect when the sun heats the ground up. Also plants on the south side of a building tend to bloom earlier than those on the north side
Cherry plants are pretty short-lived for trees typically living around 40 or 50 years. Their longevity however depends on the species. There are some types in Japan that have been bred to last more than a century.
#Why Are Tree Rings Lighter or Darker? New wood formed in a tree during spring
and summer is light in color. Toward the end of a growing season new cells formed are smaller
Near the core of a tree rings will be tighter and darker if a young tree grows up in the shade a mature forest.
Soil conditions that might change over time can also affect the growth. The patterns in tree rings tell a story explains Erin Mcmurry research assistant in the University of Missouri'scollege of Agriculture Food and Natural resources Tree Ring Laboratory.
We think of tree rings as ecological artifacts. We know how to date the rings and create a chronology
so we can tell when there has been a fire or a drought occurred and unlock the history the tree has been holding for years.
Tree rings have been used to understand everything from ancient droughts to hurricane activity before records were kept.
Mcmurry and her colleague solved a longstanding mystery by studying tree rings. On May 19 1780 it was black as night at noon.
Some people in New england thought judgment day was at hand. Accounts of that day which became known as New england's Dark Day include mentions of midday meals by candlelight night birds coming out to sing flowers folding their petals and strange behavior from animals.
The scientists announced on June 6 2008 that evidence from tree rings reveals massive wildfires as the likely cause one of several theories proposed after the event but dismissed as simple and absurd.
A couple of years later the bark falls off revealing the wood and an injury to the tree.
and a resin formation on the top that creates a dark spot said Richard Guyette director of the Tree Ring Lab at the University of Missouri.
Eucalyptus forests may also be feeding the flames. The flames are also creating their own weather as they are expected to fuel huge pyrocumulus clouds over the area
A tree stressed is a symptom that something larger is wrong with our world Neufeld wrote on his blog.
Trees cue in on both day length and temperature when moving toward leaf senescence the process that produces fall color.
Warmer fall days will make trees delay this process Neufeld said. The trees say'It's not getting colder so
I'll just keep my leaves'he said. All else being equal however a later fall start might not do much harm to the leaf-peeping season as global warming could also delay the frost
Tree migration Unfortunately all else is not equal and studies like O'Keefe's fail to account for the ways climate change might rob New england of its red leaves Neufeld said.
For one thing climate change will likely alter the suitable habitat for many of the trees that bring fall color particularly New england's prized sugar maples one of the most important contributors to fall foliage O'Keefe said.
Simulations show that climate change will push sugar maples from New england into Canada reducing the suitable habitat for these trees in the United states by 40 to 60 percent by 2100 said Louis Iverson a landscape ecologist with the U s. Forest
Service whose Climate Change Tree Atlas forecasted the shift. Though trees that currently populate more Southern states might move in to fill that space few
if any can replicate the sugar maple's brilliant red hues Iverson said. Certainly there are some ashes that turn brownish he said.
I don't think there's anything that can replace the sugar maple. Moreover those Southern trees still may not thrive in the Northeast Neufeld said.
There might not be the right soil even if the climate is said right he. Fewer reds Because it actually takes energy
and nutrients to produce the red colors of fall several other climate-related changes could dim autumn forests Neufeld said.
Yellow colors are always present in the leaves and simply become visible when the masking green of photosynthesis disappears.
By contrast trees actually manufacture their red pigment or anthocyanin in the autumn. Orange colors arise through the interplay between red and yellow pigments.
Under current conditions the fall signals of cool nights and sunny days prompt trees to temporarily store nutrients in their leaves in the form of red pigments.
But if climate change pairs hotter nights with those shorter days trees may instead burn off their sugar
That means the trees won't use that sugar to make red pigments. See Where Fall Leaves Are Turning Other factors like increased cloud cover
Invasives and other effects Warming has brought already the hemlock wooly adelgid northward devastating hemlock trees Iverson said.
and fungi into new regions invasive species could have even more dramatic effects on fall trees Neufeld said.
More frequent and more intense droughts predicted by climate change models will convince trees to simply drop their leaves before they have a chance to change hues he said.
Older sugar maples which can live 400 years may still hang on in less than-ideal conditions Iverson said.
However if and when catastrophes such as fires hurricanes or invasive species wipe out large sections of trees the new warmer conditions will prevent their replacement Iverson said.
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