As a child playing under its branches in the 1930s, Michael Jenkins Cromwell Jr. knew that the massive elm near his Baltimore County home was extraordinary. "It was the largest and oldest tree, going back to Revolutionary times," he said.
Decades later, others would be charmed by the majestic tree. Soon after buying their house near Brooklandville, Charles and Anita Stapleton decided to contact state foresters to measure the tree in their backyard.
That call set into motion a chain of events that led to their tree being recognized as the largest American elm in the nation. American Forests, a nonprofit conservation group, recently included it in its 2008-2009 National Register of Big Trees. The register lists the largest documented specimens of trees in the country.
The Stapletons' tree stands 136 feet tall, with a trunk that is more than 20 feet around. At noon on a recent warm day, its 85-foot canopy created a massive shadow under which the air felt noticeably cooler. Its large branches point to two smaller elms that likely originated from it.
The Stapletons' elm is one of 18 national champion trees in Maryland. It might be the most surprising, given the unfortunate history of the species, Ulmus americana, over the past 75 years. The elm dethroned larger co-champs in Tennessee and Virginia that fell victim to disease and storm damage, said Margo Dawley, program director at American Forests.
Dutch elm disease has taken a heavy toll on the elm since the fungus arrived in America about 1930 and was spread by beetles.
"American elm trees are rare these days due to the Dutch elm disease, which wiped out most of the stately elms which used to line the streets of our major New England and Mid-Atlantic cities," according to John Bennett, volunteer coordinator of the Maryland Big Tree Program, which nominates trees to the National Register.
Finding an elm the size of the Stapletons' tree is even rarer, he said. "Like the American chestnut, the story of the demise of the American elm as a major forest species is one of the tragedies of the American forest," he said. "We don't know how long they can avoid the Dutch elm disease, but so far they have thrived, and serve as a reminder of a different time in America."
Researchers have sought to cultivate American elms and hybrids that are resistant to Dutch elm disease. Riveredge Farms in Atlanta is selling hardier American elms online.
Tree experts say they cannot determine the exact age of a living tree. Charles Stapleton said he was told his elm dates to the 17th century. "The elm was here when the East Coast was being settled," said Stapleton, retired senior vice president for St. Paul Travelers Insurance. "It has survived centuries of storms, high winds and other events."
Cromwell, whose family owned the tree decades ago, said he also believes the tree was alive during the American Revolution. In 1934, his father bought a tract of land that included the elm. "The land was used for reforestation and bushes for the development of Roland Park and Homeland," he said.
"I spent a lot of time as a kid playing under that elm. It was a very venerable and respected tree even in those days," he said.
Anita Stapleton, a marketing consultant, realized that she had a potential champion in her backyard after reading about another national champ, the Wye Oak on Maryland's Eastern Shore. The Wye Oak was more than 400 years old when it fell in 2002.
She called a state forester, who included her elm in the state register. Her tree was measured again last August by the state Big Tree Program. Program volunteers sent the measurements to American Forests, which was looking for a new champ.
Having a tree designated as a national champion brings bragging rights, but no financial benefits, Dawley said.
Maryland is fortunate to have private landowners who have gone to the expense of caring for big trees, Bennett said. They have hired arborists to fertilize their trees and look for dead branches, installed cables to keep branches from falling off, and protected their trees from lightning, he said.
The Stapletons' elm shows signs of care dating back decades. It has several hollow pipes protruding from the trunk, left by a tree surgeon to drain sap and reinforce weak limbs in the late 1940s or early 1950s, Cromwell said.
More recently, the Stapletons hired a tree company to trim branches and fertilize. "It's a responsibility - an expensive responsibility - but I do feel it is something we should take care of for future generations," Anita Stapleton said. "We're mighty proud of it."
American Forests determines the largest tree of a species by a formula that factors in circumference, height and crown spread.
This year, the group designated 733 champion and co-champion trees in the U.S. The 18 in Maryland are:
Southern crab apple - Kent County
American beech - Anne Arundel County
Blackhaw - Montgomery County (co-champion with a tree in Virginia)
Box elder - Frederick County
Common chokecherry - Baltimore County
Kentucky coffeetree - Washington County (co-champion with a tree in Ohio)
American elm - Baltimore County
Slippery elm - Frederick County
Hazelnut - Calvert County
Mockernut hickory - Prince George's County
Shagbark hickory - Anne Arundel County
American holly - Prince George's County (co-champion with two trees in Virginia)
Honey locust - Frederick County
Bigleaf magnolia - Howard County
Black mulberry - Carroll County
Chestnut oak - Anne Arundel County
Poison sumac - Anne Arundel County
Atlantic white cedar - Harford County
Source: Maryland Association of Forest Conservancy District Boards