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Source: Pittsburgh Post-GazetteAug.存倉 11--Walking under his giant white oak tree on his Washington County farm, Paul Karpan appears calm, even meditative, with spirits high. In his 90 years, he's spent many inspired hours with the green monster."This is a landmark on this farm -- something you can kind of be proud of," he said.The mighty oak, which likely took root in the nation's earliest decades, provided shade for his beef cows, a site for picnics and a target for a few bolts of lightning, all while serving as an environmental steward of his 51-year-old Blaine Township farm. Hug this tree and your arms barely bend.Mr. Karpan keeps an eye on the old oak to assure it's still standing because he knows that "every big tree has to die off."Majestic giants like the white oak are Earth's largest organisms and among its oldest. They pierce the sky with circus-tent canopies. They filter air, water and soil, and science now tells us they rule the ecosystem to the benefit of virtually every creature and organism, including humans.But over the past three centuries, old-growth trees were chopped down for fuel, farming, development or lumber. Scientists now are realizing the consequences. Champion native trees, with their good genes and long lives that have spanned centuries, could play a role significantly more important than serving as modern spectacles of nature.PG graphic: Metrics to Measure(Click image for larger version)A highly regarded arborist known for cloning ancient trees says old giants like Mr. Karpan's are needed to save the world from climate change."It's a question mark of human beings' existence on the planet," said David Milarch, co-founder of Archangel Ancient Tree Archive in Copemish, Mich. "If we put forests back with native trees, the rest starts to heal itself, starting in your own yards or along the streets where you live."Green superheroesMore than two centuries ago, Thomas Jefferson reportedly said a squirrel could climb a tree on the Eastern seaboard and not touch ground until it reached the Mississippi River.Maps representing old-growth forests three centuries ago support that claim. Ancient forests displayed in black, show the entire eastern half of the United States solidly black. Modern maps, though, are solidly white with what appears to be only a few pepper shakes along the West Coast and Rocky Mountains.Only 2 percent of old-growth forests remain standing in the United States, with only a half percent in Europe.Mr. Milarch -- the subject of Jim Robbins' 2011 book, "The Man Who Planted Trees" -- says champion trees sport the genes of old-growth forests.He, his two sons and Archangel have successfully cloned 150 species of ancient and champion trees. Archangel is using these clones to help re-establish old-growth forests to counter what Mr. Milarch describes as the imminent environmental disaster from climate change.His team takes cuttings of fresh growth from treetops. In a process previously deemed impossible due to the trees' ages, they plant numerous fresh cuttings in nurseries to sprout many thousands of new trees that replicate the genes of ancient trees. He has cloned 2,000- to 4,000-year-old redwoods and giant sequoias.Cloning native trees in Pennsylvania, he said, could help re-establish native old-growth forests here. The cloned trees could cross-pollinate with other seedlings to regenerate ancient-tree genetics.A 2010 article that Edward F. Frank wrote for the Native Tree Society identifies patches of old-growth forests in Western Pennsylvania including Hogg Woods, Butler County; the Plain Grove Fen, Lawrence County; Six Mile Run in the Moshannon State Forest, Centre County; Sixteen Mile Run in Erie County; and Presque Isle State Park, Erie County. The 3,000-acre Cook Forest in Clarion County is the state's largest old-growth forest. Patches of old growth still exist in McConnells Mill State Park, Lawrence County; and Ohiopyle State Park and Friendship Hill National Historic Site, both in Fayette County."Old, enormous trees have a mixture of genetics and fortuitous positions in the forest," said Mr. Frank, 56, of Reynoldsville, a volunteer with the society that does tree research while documenting and celebrating notable trees. "Patches of old trees can't be re-created. You never get what's lost when you cut one down."Mr. Frank said he supports Archangel's mission to regrow quality forests in Pennsylvania and beyond."Forests, in terms of acreage, are increasing," he said, noting new trees growing on abandoned farmland. "But the forests replacing [old-growth forests] don't have a long history behind them. Certain species reliant on old-growth forests are gone. The diversity of species is lost."In addition to human destruction of forests, the emerald ash borer, dutch elm disease and the hemlock woolly adelgid also are taking their toll on old-growth trees."I'd like to see stronger protection for patches of old-growth forests," Mr. Frank said.Mr. Milarch said Pennsylvania forests have been cut down three to six times. What's left, he said, are junk trees -- a statement that brings some debate from arborists, including Mr. Frank."We've destroyed the natural filter system that's been in place for thousands of years that assured a healthy life for all living things," Mr. Milarch said. "When we cut down the forests, we did more than cut down the trees. We destroyed ecosystems for millions and millions of organisms."The clock is ticking toward a deadline to re-establish forests and neutralize climate change.Mr. Milarch said re-established old forests would process the carbon dioxide that's causing climate change. Trees use the carbon to produce wood and leaves, functioning to sequester carbon while releasing oxygen necessary for life.Trees cool Earth's surface. They store water in their canopies and retain groundwater. They neutralize mercury and pollutants. Trees provide food for insects, humans, mammals, birds and insects and transport oxygen and minerals necessary to sustain ocean life and chemistry. Trees serve as the planet's heat shield, the preface of Mr. Robbins' book says, slowing down evaporation of water and cooling the earth."They are among our best allies in the uncertain future that is unfolding."Mr. Milarch is more adamant."We have 50 to 75 years. At that time it will be questionable whether humans can live on this planet," he said. "If we don't put the filter system back in place, we only will expedite the inevitable."It can be done in two ways: We can shrug it off and nature will get rid of us and do it herself over a hundred thousand or million years to replace the filtering system and the ecosystem. It has to be done. The question is whether we do it or nature do自存倉s it."People and organizations from 178 nations have contacted Archangel with interest in joining the effort to save and expand quality forestland worldwide."We're not about doom and gloom," Mr. Milarch said. "We're about solutions. We're about hope. We're about hands-on."Cloning the champsChampion trees live among us but require time and effort to find many of them.Southwestern Pennsylvania is home to several state champions -- two oak hybrids, a handsome tamarack and an emphatic slippery elm, among several nonnative and ornamental trees.In mournful news, the former state champion white oak near Footdale, Fayette County, was felled by lightning. Its gray trunk, 22 feet in circumference, now lies on its side like some dead elephant.That means Mr. Karpan's tree has potential to be the largest white oak in the state. In 2000, it stood 100 feet high with a 115-foot canopy and a trunk more than 20 feet in circumference. That trunk supports muscular limbs weighing tons. Its height, spread and trunk circumference earned it 373 points -- only 7 behind the current state champion white oak in London Grove, Chester County.The state champion tamarack, a type of larch, sits in the backyard of Elizabeth and Regis Killmeyer in Findlay, near Imperial. When they bought the property in March 1968, they thought they'd need to cut down the dead tree, only to discover it turned green with pine-like needles later in the spring."We thought it was dead," said Mr. Killmeyer, 79. "We're rookies. What did we know?"The tamarack has characteristics of both a deciduous (losing leaves seasonally) and coniferous (bearing cones, often an evergreen) tree. This area represents the southernmost habitat for the tree, which is more common in New England and Canada.At 191 points, the tamarack is only four points ahead of its closest competitor on a National Wildlife Federation Farm in Langhorne, Bucks County . But the tree hasn't been measured for 13 years, so a new measurement could expand its lead.Southwestern Pennsylvania's highest scoring tree -- at 460 points -- sits along a paved roadway near the Kiskiminetas River in Hyde Park, Westmoreland County.Stephen Halow, an amateur arborist from Waynesburg, who measured trees last week for the Post-Gazette, used his laser range finder to determine the tree to be 1021/2 feet, not the published height of 120 feet.Its 118-foot canopy adds 4 feet to its total, with a circumference of 314 inches providing three more points. But the shorter height drops its total points by 14 to 446. It's not lost ground. It remains the region's largest tree and the fourth-largest American sycamore and fifth-largest tree in the state.Pennsylvania's largest slippery elm stands protected by metal fence in front of Town and Country Transit in Kittanning, Armstrong County. Operations manager Gerry Miller said he didn't realize the tree's prominence until he found a certificate in the files identifying it as state champion."I see people stopping to look at it all the time," he said. "We put the metal fence around it because kids would use the root system to launch their bikes to the sidewalk. I feared they would get hurt or damage the tree."Mr. Halow's measurement shows the elm to be taller, broader and fatter, increasing its point total from 313 to 320.Pittsburgh's canopyPittsburgh, with 42 percent of the city under tree cover, is one of the most canopied cities in the United States, largely due to its steep tree-covered hillsides and many parks. But Tree Pittsburgh hopes to add trees to the city streets and parks.The cooling effect of a healthy tree is equivalent to 10 room-sized air conditioners operating 20 hours a day, Tree Pittsburgh notes. Shoppers travel further and stay longer in shopping areas lined with quality trees. They increase real estate value, retain water, reduce storm runoff and improve air quality by processing sulfur dioxide, carbon dioxide and other pollutants.Matt Erb, Tree Pittsburgh's director of urban forestry, said Allegheny Commons has large elm, tulip and cucumber magnolia trees near the Community College of Allegheny County campus. The Allegheny Cemetery also has large American sycamores near the war memorial and Civil War tombstone and a notable sassafras tree with a 9-foot trunk circumference. A notable grove of Kentucky coffee trees also stands near the intersection of Darlington Road and Serpentine Drive on the Bob O'Connor Golf Course in Schenley Park.The city maintains a website of city trees, including their diameters. (Go to pittsburghpa.gov and search on "treekeeper.")"I'm sure the region has a lot of trees to knock champions off the list in Eastern Pennsylvania," Mr. Erb said. "We just have to get them measured."Big tree competitionThe Pennsylvania Forestry Association's website -- .pabigtrees.com -- includes 1,299 trees that are champions or contenders. Most are in southeastern counties due to more moderate weather, less severe winters and a greater interest in heritage trees in that region."Trees on the list tend to be 150 to 200 years old," said Scott Wade, 46, of Media, outside of Philadelphia, who is state coordinator for the association's champion tree program. "Pennsylvania was cleared of trees in the 1850s and 1900 -- just about every stick. It's very rare to find a tree in the state over 200 years old, unless it was grown at a house or barn."Many champion trees were planted in front of houses or other buildings to keep the buildings cool, or in parks, where they've been protected.The state's largest tree is an American sycamore in Mercersburg, Franklin County, with 529 points, including a canopy that would cover half a football field. It stands nearly nine stories tall with a 32-foot trunk circumference. The second-largest, an eastern cottonwood in Halifax, Dauphin County, has a trunk 30.5 feet in circumference that helps provide it with 501 points.Nine of the 10 largest trees in the state are American sycamores, including southwestern Pennsylvania's largest in Westmoreland County. The highest tree at 148 feet -- about 12 stories high -- also is an American sycamore in Forest County."People want to see the tallest building, the biggest bridge, the Eiffel Tower and Mount Washington," Mr. Wade said. "Maximums are the favorite of the human species for some reason."Then he provides the reason."When I see a big tree, I get excited."David Templeton: dtempleton@post-gazette.com or 412-263-1578. Archangel Ancient Tree Archive's website is .ancienttreearchive.com. The Pennsylvania Forestry Association website is .pabigtrees.com.Copyright: ___ (c)2013 the Pittsburgh Post-Gazette Visit the Pittsburgh Post-Gazette at .post-gazette.com Distributed by MCT Information Services迷你倉新蒲崗