What a difference a genus can make

Oak leaves


Andrew Hipp, senior scientist at The Morton Arboretum, and an international team of 24 scientists, in 2019 published a paper in New Phytologist tracing the 56-million-year global history of oak (Quercus) diversity. The team used DNA sequencing, genomic mapping and fossil data to investigate one of the most diverse, abundant and important woody plant groups to the ecology, economy and culture of the northern hemisphere.


Like many trees, oaks around the world are under pressure from disease, loss of habitat and in some cases, lack of post-harvest regeneration, threatening the delicate balance of forest ecosystems and economies that depend on them.


Red oaks (Q. rubra)) and white oaks (Q. alba) are two of Missouri’s most common oak groups. They vary in leaf shape, bark expression and acorn palatibility. White oak leaves typically exhibit lobes with rounded ends, while red oak leaves vary in appearance, generally with more pointed lobes. In most cases, oak leaves emerge red in spring, turn dark green in summer and in fall, turn shades of burnished red, brown and gold.


White oak bark occurs in shades of gray and exhibits a scaley appearance. Red oaks’ much darker bark features deep furrows and crisscrossing ridges. Reds produce acorns with high amounts of fat and tannin, making them bitter compared to white oak’s sweeter, more palatable nuts. Trees from both groups occur across the country, however, whites have more eastern species and reds have a larger presence in the western states.


Additionally, white oaks tend to live longer and are more majestic than reds, both characteristics that make them great choices for Missouri landscapes. This is a closer look at white oaks in the Show-Me state.

The importance of oaks to Missourians


Oaks play a key role in the ecosystems of Missouri. They are a fundamental species in the forests of this state, providing critical food, habitat and shelter for animals, birds and insects. Wild turkeys, quail, jays, bear, deer, opossums, raccoons, squirrels and many other species thrive on the trees’ tasty and nutritious acorns.


Entomologist Doug Tallamy in 2007 published a landmark book, Bringing Nature Home: How you can sustain wildlife with native plants, which details his observations about the role humans play in biodiversity’s intricate web. He makes the compelling case that oaks planted in residential landscapes also can serve as powerful tools for conservation.


Tallamy found that white oaks support 537 species of butterfly and moth caterpillars — critical food for 95 percent of young songbirds in the important early months of their lives. Tallamy holds that if you can plant only one plant for wildlife or the environment, oaks should be your top choice.


MU Associate Professor of Forestry Extension Hank Stelzer recently shared information about a national White Oak Initiative launched to ensure the long-term sustainability of these versatile trees. Existing white oak stocks are currently sufficient to meet the demand for oak hardwood products, but forest monitoring and long-term projections indicate problems in maintaining high-quality white oak regeneration.


Local economies across the country, including many in Missouri, are the recipients of billions of dollars generated from forest product industries reliant on white oak lumber for such things as furniture, flooring, cabinetry and barrels for wine and spirits. Oaks also boost many community’s economic gains from recreational activities such as hunting.


Without action, it is estimated oak forests will disappear within a generation significantly impacting wildlife, forest ecosystems and wood product industries.


In the past, many individuals, businesses and organizations have worked in support of white oaks, but this new initiative introduces a coordinated, large-scale response to oak decline and includes private landowners, universities — including MU — state and federal agencies, conservation organizations, trade associations and forest industries. Initiative actions include supporting research, public and private technical assistance, on the ground implementation and communication strategies and policy solutions.


For more information or to get involved, =contact initiative director Melissa Moeller or visit the website.


Mizzou Botanic Garden (MUBG) and the University of Missouri campus have chosen to replace the declining pin oaks on the Francis Quadrangle with white oak species. Designated tp the Legacy Oaks project, five varieties of white oak saplings were donated by Wayne Lovelace and Kim Lovelace-Hainsfurther of Forrest Keeling Nursery, and are now growing to planting size on MU’s South Research Farm.


MUBG selected and donated two of the Legacy Oaks to the State of Missouri, which were planted on the grounds of the capitol in Jefferson City in commemoration of the state’s bicentennial celebrated on August 10, 2021. Chances are good that these Legacy Oaks will be grandly flourishing on both MU’s Francis Quadrangle and at the Missouri statehouse lawn 200 years from now.


White oaks are best planted as young trees/saplings, growing quickly in their youth and slowing over the course of their long lives. As a species, they are more resistant to current climate pressures of wetter springs, hotter summers and prolonged drought, but even these most adaptable of trees may require some root zone protection and watering in weather extremes.


White oaks can live for centuries, enhancing the MU campus, greeting visitors to the Missouri capitol, adding diversity to the state’s many forested acres and serving as a nutritional resource for untold wildlife.


As Michael Dirr, nationally known horticulturist, woody plant expert and co-author of the “The Tree Book”, noted on a visit to MUBG in 2018, “I’ve spent my life embracing noble trees. When you plant for the future, plant for nobility. Plant oaks.”



Plans for MU’s Legacy Oak restoration project are evolving. Tree sponsorship and formal recognition of significant contributions are currently being discussed. Contact the Garden to find out more about this project and how you can help.



Story by Jan Wiese-Fales