Haunting alluvial river bottoms and creek beds across the Deep South, is a highly unusual oak species, Overcup Oak (Quercus lyrata). Unlike nearly any other Oak and most sane people, Overcups occur deep in alluvial swamps and spend most of their lives with their feet wet. Though the species hides out along water’s edge in secluded swamps, it has nevertheless been discovered by the horticultural industry and is becoming one of the favorite species of landscape designers and nurserymen around the South. The reasons for Overcup’s rise are numerous, let’s dive into them.
First, much of the deep South, especially in the Coastal Plain, is dominated by poorly drained flatwoods soils cut through by river systems and dotted with cypress and blackgum ponds. These conditions call for landscape plants that can handle hot, humid air, excess rainfall, and even periodic inundation (standing water). It stands to reason our best tree options for these areas, Sycamore, Bald Cypress, Red Maple, and others, occur naturally in swamps that mimic these conditions. Overcup Oak is one of these hardy species. Overcup goes above and beyond being able to handle a squishy lawn, it is often found inundated for weeks at a time by more than 20’ of water during the spring floods our river systems experience.
The species has even developed an interesting adaptation to allow populations to thrive in flooded seasons. Their acorns, preferred food of many waterfowl, are almost totally covered by a buoyant acorn cap, allowing seeds to float downstream until they hit dry land, thus ensuring the species survives and spreads. While it will not survive perpetual inundation like Cypress and Blackgum, if you have a periodically damp area in your lawn where other species struggle, Overcup will shine.
Overcup Oak is also an exceedingly attractive tree. In youth, the species is extremely uniform, with a straight, stout trunk and rounded “lollipop” canopy. This regular habit is maintained into adulthood, where it becomes a stately tree with a distinctly upturned branching habit, lending itself well to mowers and other traffic underneath without having to worry about hitting low-hanging branches. The large, lustrous green leaves are lyre-shaped if you use your imagination (hence the name, Quercus lyrata) and turn a not-unattractive yellowish brown in fall. Overcups especially shines in the winter, however, when the whitish gray, shaggy bark takes center stage. Overcup bark is very reminiscent of White Oak or Shagbark Hickory and is exceedingly pretty relative to other landscape trees that can be successfully grown here.
Finally, Overcup Oak is among the easiest to grow landscape trees. We have already discussed its ability to tolerate wet soils and our blazing heat and humidity, but Overcups can also tolerate periodic drought, partial shade, and nearly any soil pH. They are long-lived trees and have no known serious pest or disease problems. They transplant easily from standard nursery containers or dug from a field (if it’s a larger specimen), making establishment in the landscape an easy task. In the establishment phase, defined as the first year or two after transplanting, young, transplanted Overcups require only a weekly rain or irrigation event of around 1” (wetter areas may not require any supplemental irrigation) and bi-annual applications of a general purpose fertilizer, 10-10-10 or similar. After that, they are generally on their own without any help!
If you’ve been looking for an attractive, low-maintenance tree for a pond bank or just generally wet area in your lawn or property, Overcup Oak might be your answer. For more information on Overcup Oak, other landscape trees and native plants, give your local UF/IFAS County Extension office a call!