In tough urban conditions it is hard to find attractive shade trees. The soil is often poor, the air polluted, and diseases are rampant. The Exclamation!™ London Planetree was created to satisfy this need – and it does. This deciduous specimen tree is beautiful and tough. It has been bred to be resistant to disease and to withstand the frost cracking that limits the northern distribution of this tree. Like all London Planetrees it will grow where no other tree will, in soils that are wet or dry, and in cities with high levels of air pollution. Amazingly, not only is it tough, it is beautiful – outstandingly beautiful, and ideal for a large specimen tree everywhere, even in a rural garden, or simply anywhere at all.
Growing EXCLAMATION!™ London Planetrees
The Exclamation London Planetree grows rapidly; it will add 3 feet a year to its height when young, gradually slowing to 12 to 18 inches a year when mature. It will soon become an outstanding specimen and in just a few decades it will be a large tree 60 feet tall and 45 feet across. Make sure the place you plant it in is big enough to accommodate a large tree. Younger trees will have branches right to the ground, and they will look beautiful on a lawn. This tree can also be pruned up, by gradually removing the lower branches, into a specimen with a clear trunk to any height you choose.
The leaves are large, up to 12 inches long and across, with three large lobes, looking a little like a maple tree. In fall the leaves may turn yellow, and then brown, before falling. The bark is the most outstanding feature of this tree, and it makes it as interesting in winter as it is in summer. From an early age the tree shows bark that is mottled in shades of brown, green and tan. The bark regularly peels off in large pieces, and then we see the bright cream and white young bark beneath. Don’t worry when this begins to happen – your tree is growing normally.
Planting and Initial Care
Plant the Exclamation London Planetree is full sun, although it can be planted in shade if it will soon grow up into the sunlight. It will grow in any soil, from acid to alkaline, and unlike almost any other tree available, this tree grows in wet soil, ordinary soil, and dry, droughty soil too. Once established it is very drought resistant. It also tolerates highway fumes and other forms of urban pollution, so for a city garden it is ideal.
Pests and Diseases
Diseases can be problems with ordinary forms of this tree, and this is where its special breeding comes into play. Anthracnose, causing summer browning of leaves, and twigs to die back, is a serious disease, but the Exclamation London Planetree is resistant to it. It is also partially resistant to the less-serious but unsightly powdery mildew that can attack these trees in hot summers. As well, often they split and crack in the hard frost of cold areas, but this tree will not, so it can be grown a whole zone colder than other forms – throughout zone 4. All these features make it an outstanding choice for colder areas, and a top-pick for city planting.
History and Origins of the EXCLAMATION!™ London Planetree
The Exclamation London Planetree is a carefully selected form of the London Plane Tree, a tree with a long history. Perhaps as far back as 1670, in a botanical garden in England, a chance cross-pollination happened between the Oriental Plane Tree, Platanus orientalis and the American Sycamore, or Buttonwood (Platanus occidentalis). The Oriental Plane grows throughout Europe and east to Iran, while the American Sycamore grows all across eastern and central America.
The result of this chance event was a hybrid tree combining the best features of the two trees, and which also produced seed that could be used to produce further plants. This probably happened several times, so that there is now a group of hybrid trees with tiny variations between them, all called Platanus x acerifolia. Among them is the London Planetree, a tree growing all over that city and familiar to visitors. In Europe, where they are seen everywhere, grown for their toughness in harsh urban conditions.
The search for improved forms of popular garden plants that will grow well, and be more successful under difficult conditions, goes on all the time. Chicagoland Grows® is an innovative partnership between the Chicago Botanic Garden, The Morton Arboretum, and the Ornamental Grower’s Association of Northern Illinois (OGA). The OGA brings together several wholesale nurseries growing plants in northeastern Illinois. The goal of this group is to promote new varieties of trees and plants ideal for growing in the Upper Midwest – but of course they grow just as well in other similar zones, and they have been promoted all around the world.
The London plane tree variety called ‘Morton Circle’ was developed at the Morton Arboretum, by Dr. George Ware. He repeated the original natural origin of the London plane tree by crossing a plant of Old-World Sycamore growing at the US National Arboretum with a disease-resistant plant of American Sycamore that grew at the Morton Arboretum. He grew many seedlings, and in 1994 selected the very best ones. The one he called ‘Morton Circle’ had outstanding resistance to anthracnose disease, and to frost-cracking in cold conditions. It was registered as Exclamation! and released by Chicagoland Grows to nurseries across the country.
This tree must be grown from stem pieces, not from seed, and this is how our trees are grown, so that you get exactly the result of all the careful breeding work. Top-quality shade trees for difficult locations are always in high demand, and we know these great trees will soon be gone to happy homes. Order now while we still have stock available – don’t hesitate.