Dr. Dirr’s Tree Spotlight: Quercus shumardii – Shumard Oak

Quercus shumardii fall color University of Georgia

Shumard oak is one of the most widely distributed species of the red oak group ranging from Ontario (4 counties) to Florida, west to Kansas, Oklahoma, and Texas. In nature, it occurs on mesic slopes, bluffs, bottom lands, stream banks and poorly drained uplands. A report from Mississippi, indicated good survival and growth on 25-year-old plantings in pH 7.8 to 8 alluvial soils along the Mississippi. Under cultivation, it adapts to heavy soils, pH variation, heat and drought. Considered zone 5 to 9 as far as temperature adaptability.

Quercus shumardii Milliken

At the Milliken Arboretum, Spartanburg, SC, trees averaged 2’/year over a 20-year period. The late Dr. John Pair, Kansas State University, tested species for prairie conditions and reported Shumard averaging 1’ 3.4” /year over a 10-year period. The 13-year Auburn University shade tree evaluation ranked Shumard as a superior performer. Annual growth was 2.94’ during the evaluation period with consistent red fall color.  In fact, it outgrew all the red maples in the trial. On the Georgia campus, Shumard has been one of the best oaks during my 38-years in Athens.

Reasonable/logical question to ask is why the paucity in commerce. Red, Q. rubra, and pin oaks, Q. palustris, dominate perhaps because of long-time use, familiarity, availability and the relative ease of transplanting. I witness Q. nuttallii establishing a toe-hold in southeastern nurseries and landscapes. It is similar to Shumard in certain characteristics (q.v.) but not as cold hardy.

Quercus shumardii Fall Color Depot Tree 2 Year Seedling

Shumard is a beautiful tree in youth, pyramidal-oval, with upswept branches and dense foliage canopy, usually with a central leader. Old trees become more rounded, 40 to 60’ high and wide. The national champion is 94’ high and 101’ wide, estimated between 300 and 350 years. In the Congaree National Park, SC, the fallen former national champion measured 127.5’ in height. In the Missouri Botanical Garden, St. Louis, resides the most impressive specimen I have observed (see photo).

Foliage is elegant, shining dark green, persisting late and coloring yellow-orange to red, never consistent from tree to tree. In fact, on the Georgia campus in mid-November, trees may be green or with fully expressed fall color. I hypothesize this relates to seed source origin with the green leaf types from southern seed sources; the early fall coloring trees from more northerly provenances.

The 4 to 6” (8”) long, 3 to 4” wide leaves are 7 to 9(11)-lobed with deeply cut sinuses almost to the midvein.  They are glabrous except for tufts of brown hairs in the axils of the veins on the lower surface. The winter buds provide a reliable characteristic to separate the species from red, pin and scarlet (Q. coccinea) oaks. The gray-brown coloration and indiscernible scale edges, compared to the red-brown scale coloration and clear scale delineation permit separation. The closely related Q. nuttallii has similar bud and leaf features but differs in acorn traits. Shumard has cups (caps) with rounded bases covering ¼ to 1/3 of the nut; Nuttall with a deeply turbinate cup covering 1/3 to ½ the nut. Even armed with these bench marks, absolute identification can be frustrating.

Through the years, I have germinated numerous Shumard acorns with a resultant splendid, red fall-colored, 15’ high specimen in the garden. Acorns were collected from a bright red, fall coloring tree (see photo) in the local Home Depot parking lot on a November day. As I scrounged for acorns, several drivers asked if I needed assistance and offered hot chocolate and/or a ride to Mcdonalds. I have shared these seedlings with friends who reported excellent red fall color.  Acorns require cold moist stratification so I plant them in a container, protect from predators and place outside. The end of the first growing season they are root pruned and planted singly in a 3-gallon container. By the second growing season, the seedlings are 4 to 6’ high and ready for out-planting in the garden.

Several southeastern nurseries have introduced own-root clones of Shumard with improved habit, and foliar features such as fall color. To date, I know of Madison ™ (‘ACNRT1’, pp15,226)-fastigiate to narrow- oval, 60’ by 20’; Panache® (‘QSFTC’, pp14,424)-broad-pyramidal, glossy dark green foliage, red in autumn, 60’ by 50’; and Prominence® (‘QSSTH’)-pyramidal to broad-pyramidal, good red fall color, 65’ by 45’.

 

 

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