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SOUTHERN PINES -- Graduate student Jason Ortegren's research project features a 459-year-old window that looks back on the past not through glass, but through wood. Living wood.

As part of his research at UNCG, Ortegren and geography professor Paul Knapp have discovered what might be the oldest living longleaf pine in North America, which is to say the oldest in the world.

But if you're envisioning something majestic, something like a gigantic redwood from the West Coast, think again.

"No layman would ever think that tree is how old it really is. It's stunted. It's gnarly," Ortegren said, a note of wonder and excitement creeping into his academic demeanor.

"I walked right by it. It looks unimpressive in most of the ways you can look at a tree," Ortegren said. "It was (Knapp) who said, 'Why don't we core this one?' "

Coring is the process by which a long, narrow plug is removed harmlessly from a tree to reveal the interior rings that document its age and some of the conditions under which it has lived.

The two scientists from the UNCG Tree Ring Science Lab made their discovery this summer at the state-owned Weymouth Woods Sandhills Nature Preserve in Southern Pines, pinpointing the tree's first reliable evidence of life in the year 1548.

Imagine a life span that extends from the era of American Indian supremacy and the Spanish conquistadors to the Industrial Revolution, interstate highways and the international space station.

But perhaps the most fascinating aspect of Ortegren's find is the larger purpose it could serve, a purpose that makes crystal clear the value of preserving large swaths of nature.

Ortegren is writing a doctoral dissertation focused on drought — massive and unrelenting drought that might make the Triad's current dry spell look like a blip on the radar.

He is seeking cycles of climate measured by the century, not by the year or decade, cycles at a scale that might suggest, for example, that every 150 or 200 years North Carolina suffers a whopper drought lasting for 10 consecutive years.

He pursues this quest by examining the growth rings of ancient longleafs and other trees, teasing out North Carolina's cycles of abundant rainfall and extended dry spells by analyzing the evidence buried deep in each trunk.

Reliable weather records go back only about 100 years, so the evidence in ancient trees can lengthen the rear-view mirror by centuries.

What Ortegren learns, when compared with similar studies, could foretell or diminish the threat of a monster drought here on the order of the 1930s drought that devastated Oklahoma and the Great Plains.

The question is critical for Greensboro, which has no large river to tap and is uncommonly dependent for a city of its size on relatively recent rainfall.

"Our resources are finite in an area without any big rivers and no large, natural lakes," Ortegren said. "And yet, the population is growing here at one of the faster rates in the country."

It could take Ortegren up to a year to develop and analyze his data. So, he doesn't know what his research will conclude about long-term droughts and which areas are most prone to them.

He works with Knapp and fellow grad student Bill Tyminski in UNCG's tree ring lab, which the professor opened three years

ago in the geography department.

"Historically, the Piedmont has not had a lot of tree research done, partly because it is so hard to find older trees in this region," Knapp said.

But Weymouth Woods is an excellent place to look for such relic trees. It was owned for years by a family that resisted logging or other industrial uses, then bequeathed it to the state in 1963.

"We've known it's had these aged trees on it for some time now," Weymouth Woods ranger Kim Hyre said. "All of them are about the same age, but you can't get a viable age on some of them."

That's because they have survived hurricane damage, diseases or other natural events that can blemish key parts of their ring structures, she said.

There also could be other trees in the same stand or nearby that predate the one found by Ortegren and Knapp, but have yet to be cored, Hyre said.

Regardless, the 459-year-old tree is a remarkable discovery, said Henri Grissino-Mayer, an expert on the longleaf pine who teaches at the University of Tennessee-Knoxville.

"We have found older longleaf pines but they are all dead now," Grissino-Mayer said. He noted that the oldest on record lived 490 years in Florida.

"Finding a longleaf pine dating back that far is exceedingly rare, extremely exceptional."

Once, such a find would have been more common. Much of North Carolina was a vast sea of longleaf, part of a piney domain that stretched from southeastern Virginia to the Texas coastal plain. North America is the only place in the world where the longleaf thrives, partly because of its unique life cycle that depends heavily on periodic wildfires of low intensity to clean out and enrich the terrain.

It took European settlers little time to begin making a big gash in this seemingly endless resource, starting in the 18th century. Settlers felled tree after tree for farm fields and ship building.

Other trees were damaged by workers tapping them for the sap that made turpentine and other products.

"Remember, when you think about this very old tree, that 97 percent of the longleaf pines that used to exist are gone now," Grissino-Mayer said.

Knapp said his eye was drawn to it by telltale signs of great age that the average person probably would overlook in such an otherwise nondescript tree: A very high lowest branch.

The flat-topped, upper tier of branches that the longleaf begins to develop at middle age, after 250 to 300 years of life.

But it also was just a hunch, Knapp acknowledges. "Part science, part luck," he said.

Dendroecology, the science of deciphering the rings of such ancient trees, sounds deceptively simple.

For every year of life, the tree adds a circle of growth that gets encapsulated by the next year's new ring, which is engulfed by the next year's, and so on for up to 500 years if the tree is a longleaf.

A wide ring suggests a favorable year with sufficient rainfall amid other positive conditions, while more narrow bands hint that a lack of rain or some other factor hindered growth that year.

Dendroecologists correlate the diary provided by each tree with records from other nearby specimens, with similar trees farther away and with trees of other species in the same general region.

For example, Ortegren is conducting another part of his research at South Mountains State Park near Morganton, where he is looking

for the same sort of drought evidence in the cores of aged chestnut oaks.

He also will correlate his data with information collected by other tree ring scientists looking at other parts of the region.

That way, he can have confidence that his study focuses on large-scale drought, rather than getting sidetracked by events that affected a single tree, a small group or just one species.

"There are always a few oddball trees when you bring their cores back to the lab," Knapp said. "They don't correlate with the others."

Each core is about the diameter of a drinking straw and is stored in an elongated paper wrapper until it is brought back to the lab for analysis.

Next, it is glued onto a narrow, wooden tray with a groove in the middle to accommodate the sample.

The core is then sanded down, level with the edge of the tray so "the ring structure really pops out," Knapp said.

Scientists then can study the patterns under a microscope, marking off the years and decades in pencil on the side of the tray and compiling a record of the past that can suggest a future decades or centuries away.

But the year-by-year markings don't take up a lot of space. So there's usually room on the side of each wooden tray for the scientist to make additional notes or observations.

The first such penciled entry on the tray that Ortegren prepared for his and Knapp's remarkable find speaks for itself: "1548!!!"

Contact Taft Wireback at 373-7100 or twireback@news-record.com