Feb. 15, 2013
LINCOLN, Neb. — Tucked away near the Kansas-Nebraska border, in Richardson County, stands a rare native population of oaks that for more than a decade has played an integral part in Nebraska's landscape conservation. A recent Nebraska Forest Service project helped safeguard this unique stand of dwarf chinkapin oaks that grows in shallow soil over limestone. Preserving this native habitat is essential; the tree is listed as threatened in eight states.
More than a dozen people – landowners, neighbors and volunteers interested in landscape conservation – recently cleared hundreds of aggressive eastern redcedar trees that threatened the existence of the oaks, which according to the USDA is the westernmost occurrence of the species in the United States. Neighbors were especially interested in the uniqueness of the stand, and they wanted to learn how to identify the oak species and the best approach to managing the shrub oaks that might be growing on their own properties.
The aggressive eastern redcedar dramatically affects Nebraska's natural resources by rapidly encroaching on native tree stands and into agricultural fields, pastures and grazing lands, and forests along the Platte and Niobrara rivers.
The NFS learned about the importance of the property from Guy Sternberg, an international expert on the oak species. Overlooking the river valley, the site is a short distance from property selected in 1855 by a relative of President Abraham Lincoln and two others as an ideal place to locate a business, according to the "History of Richardson County, Nebraska" by Lewis C. Edwards.
For the past 12 years, property owners have allowed NFS foresters access to the property to collect acorns for propagation. Since then, the Nebraska Statewide Arboretum, part of NFS, has been able to supply acorns and seedlings for distribution to local wholesale growers and regional and national growers interested in preserving the rare oak.
"Without access to those acorns it would be difficult to find a native population of this size that can supply a pure strain," said Bob Henrickson, NFS Horticulture Program coordinator. "We've been able to collect as much as 90 pounds of acorns a year on the property."
In 2001, there was no demand for the acorns from these dwarf chinkapin oaks. But with NSA's efforts, nursery growers now are able to offer the native tree for conservation habitat and urban landscapes. Acorns from this tree are highly sought after by wildlife because they have few tannins to create a bitter taste.
Dwarf chinkapin oak grows in the central Midwest east to New York and Pennsylvania on dry, often rocky sites. The plants have attractive, shallowly lobed leaves and dark brown acorns and can reach 12 to 15 feet in height and width. According to NFS foresters, the Richardson County stand includes more than 150 plants that grow in association with a variety of other species such as bitternut hickory, eastern redbud, northern red oak, bur oak and little bluestem. Located on a high ridge or prairie knoll, the site is very rocky and has well-drained soil.
"You can grow this tree as a large many-stemmed shrub with picturesque branching or prune it into a single trunk to expose its gray, flaky bark," said Henrickson. "The plant can tolerate high winds, extreme drought and has been hearty to 40 degrees below zero."
According to Henrickson, this species meets consumer demand for small trees that are native, durable, ornamental and compact, since many property owners don't have room to plant oaks that grow taller than 15 feet. Preserving the unique site is crucial to the future of Nebraska's dwarf chinkapin oak.
For more information about this tree species or other NFS conservation projects, contact Bob Henrickson at firstname.lastname@example.org or visit the NFS website at nfs.unl.edu.Bob Henrickson
NFS Horticulture Program
IANR News Service