Andrew Sawyer, National Big Tree Registry, measures a dwarf hackberry tree.
KALAMAZOO—One of Western Michigan University's 29 dwarf hackberry trees has been declared the Michigan State Champion while two others have been designated Michigan Co-champions.
That news came March 14 after Andrew Sawyer, the state's official representative for the National Big Tree Registry, measured three of the largest dwarf hackberrys discovered so far on campus property.
The WMU students and landscape services staff who found the University's dwarf hackberrys had hoped one would also be the National Champion. But none of the biggest campus trees could match the thick girth of the nation's reigning tree.
Dwarf hackberrys (Celtis tenuifolia) are native to Michigan, but this tree species rarely grows this far north. The trees are listed as a species of special concern in Michigan and also are protected under Canada's Species at Risk Act.
Stephan Keto, WMU's manager of natural areas and preserves, notes that the 29 trees found in woodlots southeast of the University's Stadium Drive Apartments are the first dwarf hackberrys to be reported growing in Kalamazoo County, and they number among only a few known to exist in the state.
Keto says volunteers and University staff members are working to protect and conserve the trees by removing invasive species, establishing associated native plants and managing the area to encourage the trees' survival.
Big tree registries
The National Register of Big Trees is maintained by American Forests, the only national nonprofit organization focused exclusively on protecting and restoring forests, and any specimen on it is considered a National Champion Tree.
A point system is used when making official measurements for the registry, and when two or more trees have scores that fall within five points of the leader, they are listed as co-champions.
The total number of points awarded equals the sum of a tree's height in feet; trunk circumference, or girth, in inches; and one-quarter of the average crown spread in feet.
All 50 states and the District of Columbia have their own registers, which use the same point system. In Michigan, the Michigan Botanical Club Big Tree Program keeps track of the state's largest trees.
WMU's champion trees
Keto says WMU's top tree beat the national record holder, a specimen in Alexandria, Va., in all but the girth category. The University tree stands 50.1 feet tall and has a 13-foot crown compared to Alexandria's 41-foot specimen with a 10-foot crown.
"We came in with 99.1 points overall when our tree's circumference of 36 inches was added in. But the current National Champion has a circumference of 60 inches. That pushed up its point total to 111," Keto says.
"We're hoping that with the conservation work we're doing, our trees will flourish and we'll take the title in the future. In the meantime, we've submitted our numbers to the national registry. We don't wish harm to befall any large tree, but we're prepared to take the title should nature intervene."
WMU's State Co-champion trees also beat the National Champion in all but the girth category. Their respective points for height, crown and girth and overall totals are: first co-champion, 50.2 feet, 12.75 feet and 35.1 inches for 98 total points; and second co-champion, 46 feet, 15.3 feet and 35.5 inches for 96.8 total points.
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