BROOKINGS, S.D. – Choosing trees suited to South Dakota will be more difficult now that the threat from emerald ash borer makes it inadvisable to plant ash trees, but SDSU Extension Forestry Specialist John Ball has some suggestions.
“By now most South Dakotans are aware of the potential threat of emerald ash borer so green ash, black ash and white ash, all popular trees, have been taken off the list of trees to plant. Our climate and soils further limited what will grow here. However, there are still lots of possibilities available throughout the state,” Ball said.
One of Ball’s top recommendations is bur oak (Quercus macrocarpa), a tree native to much of the state and one of South Dakota’s toughest trees.
“It is often overlooked for planting as there is a misconception that it is a slow-growing tree. Not true, the tree can grow more than two feet a year, once established, in much of East River and the Black Hills region,” Ball said.
Another of Ball’s favorites is the swamp white oak (Quercus bicolor). The foliage on this oak has a light underside, a nice contrast against the glossy green top when the wind blows. The tree is adapted to much of the state but should probably not be planted on soils that have a pH higher than about 7.5 or the leaves may become chlorotic.
Another excellent choice is the Triumph elm Ulmus (‘Morton Glossy’).
“This is a Dutch elm disease tolerant tree, and while any elm can contract the disease through root graft infections or spores carried by beetles, this tree is not likely to die from the disease,” Ball said. “It has an upright arching habit, similar to our American elm, and the foliage is a bright shiny green. This tree and the Accolade elm (Ulmus ‘Morton’) both deserve further planting in our state as they are hardy and adapted to a wide range of soil conditions. The growth rate on each of these can be as great as five feet per year while the tree is young, probably our closest ‘instant shade’ trees.”
Also among Ball’s recommendations: the Autumn Blaze and Sienna Glen maples (Acer x freemanii ‘Jeffersred’ and A. x freemanii ‘Sienna’).
“These are excellent trees, the fall color is outstanding and the ones planted in Brookings never fail to turn a bright red around the end of September. The growth rate can also be extremely fast, more than three feet per year. The only problems are some winterkill on the Autumn Blaze, particularly those planted north of U.S. Highway 212, and these trees may become chlorotic on very alkaline sites.”
Ball adds that Aberdeen foresters have wondered if these maples are becoming too popular in some areas and if South Dakota might have a problem with overplanting in the future.