Accolade® Elm

The tragic loss to disease of millions of American elms in the 20th century still hurts. Although fewer people today have direct memory of the grand avenues of that majestic tree that lined the streets of so many towns, the loss still lingers. There is always an interest in restoring that tree, and a demand for resistant varieties. Some have been relatively successful, but to capture the unique vase-shaped look of the American elm, with its tall trunk and broad arching crown, is difficult. Yet throughout those decades of loss, another elm tree that looks a lot like the American elm stood at an arboretum in Chicago, largely unnoticed. Since it was planted in 1924 it has survived through three epidemics of Dutch elm disease, while that plague killed millions of other trees. Now its value has been realized, and in 2002 Mayor Daley chose this tree to replant elms in Chicago’s Grant Park. Across the country it is being planted with success, so if you love elm trees, and if you want an enduring tree, you should choose the ACCOLADE™ Elm.

Growing the ACCOLADE™ Elm

Size and Appearance

The Accolade Elm is a tall deciduous tree with a strong central trunk and high crown, which has a characteristic arching, rounded form, with broad spreading upper limbs. The bark of mature trees is a dark, silvery gray, with long, deep vertical furrows running up and down it. This tree is fast growing when young, adding around 3 feet to its height each year. It will grow to over 30 feet tall and 15 feet wide within the first 20 years. The growth rate falls to 1 or 2 feet a year by then, but this tree will ultimately grow to around 60 feet, with a crown up to 40 feet across.

The shiny dark green leaves are smaller than on the American elm – they are typically about 4 inches long – but larger than the Siberian (Chinese) elm. They are broad ovals, tapering to a pointed tip, and with the characteristic ‘off-set’ attachment seen in elm trees. The veins are prominently V-shaped, and the edges of the leaf are broken up into attractive jagged serrations. In fall the leaves turn a rich, dark, golden yellow, making a lovely display at that season. Flowering is inconspicuous.

Using the ACCOLADE™ Elm in Your Garden

As a grand specimen tree on a lawn, the Accolade Elm is very hard to beat. Reproduce the avenues of old by planting a row along a driveway or your property line. Fill a corner of your yard with one, growing above your smaller flowering trees. Plant it beside the house – allowing plenty of room for its ultimate size – for great curb appeal. This is such an iconic tree that it should be planted anywhere and everywhere.

Hardiness

This tree is perfectly hardy in zone 5, and all the way into zone 8, with good growth across a wide range of climate zones.

Sun Exposure and Soil Conditions

The Accolade Elm should be planted in full sun or partial shade, with at least 4 hours of direct sun each day. Usually if planted in some shade it will grow up into the sunlight in time. It will grow best in any moist, well-drained soil, but established trees have good drought tolerance. It grows well in both acidic and alkaline soils, but not in poorly drained and regularly water-logged soils. It is relatively resistant to salt spray and salt runoff.

Disease & Pest Resistance

The most important consideration when planting elm is its resistance to the lethal fungus Dutch elm disease. Spread by beetles that deposit the spores beneath the bark, there is little point in planting an elm that is not resistant, because sooner or later it will succumb. The original Accolade Elm withstood three devastating epidemics since 1924, and even some trees that did become infected made good recoveries. This tree also shows good resistance to elm yellows, another serious disease, and to the less important but still troublesome elm leaf beetle. The tiny European elm tree weevil can sometimes be a minor problem, but all the major issues of elm are resisted well – plant it and relax, while it grows to full maturity.

Maintenance and Pruning

Some formative pruning is recommended as your Accolade Elm grows and develops. Prune only between mid-October and mid-April, for disease control. Watch for the possible development of two leading vertical stems (called co-dominance) and remove the weaker one before the stems thicken too much – there should be one clear central stem growing up. If you see any side-branching rising very sharply, creating a tight, narrow fork, remove them, leaving branches with wide, U-shaped junctions to the main stem. This protects against future weakness and potential breakage. Water young trees well, and no other special care is needed.

History and Origin of the ACCOLADE™ Elm

The Accolade Elm has a complex back story. It originated at the world-famous Arnold Arboretum in Massachusetts, as a seed among many collected from an Elm tree there. By 1924 it was a young tree growing on the grounds of the Morton Arboretum, in Lisle, Illinois, outside Chicago. Although the leaves are smaller, experts were struck by its resemblance to the American elm, Ulmus americana. At first it was thought to be a unique plant of the Texas cedar elm, Ulmus crassifolia, but later it was confirmed to be a hybrid between two Asian species, the Japanese elm (Ulmus davidiana var. japonica) and Wilson’s elm (Ulmus wilsoniana), from China. However, taxonomists have now decided that Wilson’s elm is only a form of the Japanese elm, which means the Accolade Elm is no longer considered a true hybrid, but a tree resulting from the cross between a Chinese and a Japanese form of the same species. Whatever the complexities of naming it botanically, it was given the variety name ‘Morton’, recognizing where it was found (and where the original tree still grows), and trademarked with the name ACCOLADE™ to benefit Chicagoland Grows, Inc., a not-for-profit group developed by Morton Arboretum and the Ornamental Growers Association of Northern Illinois, to promote hardy and reliable trees and shrubs.

Buying the ACCOLADE™ Elm at The Tree Center

We know how loved the American Elm was, and we are excited to have this perfect replacement to offer you. Disease resistant and fast-growing, it has exactly the look that made the American Elm tree such an icon. The demand for these trees is always high, and the supply is limited, so order now, while we still have plants available to ship.