Species: Platanus orientalis ‘Autumn Glory’ & ‘Digitata’ (Hillier Nursery Form)
Common name: Oriental Plane Tree
The entire group of P. orientalis cultivars grown in Australia as “digitate” planes is problematic as they do not conform to any listing of P. orientalis found elsewhere in the world. Roger Spencer discusses this issue in some detail in the Horticultural flora of south-eastern Australia. We are using two cultivar names to indicate which planes we have, and are taking the name “Insularis” to equal the cultivar ‘Autumn Glory’.
‘Autumn Glory’ comes from the New Zealand nursery Duncan & Davies, and was first listed in 1973. Autumn Glory Plane grows to a smaller tree than most “digitate” planes, rarely reaching 15m, although with time, some may grow to 18m. It is typified by relatively small foliage (to 15cm long) that has deep sinuses and 5 lobes. The bark is flaking, and produces a mottled appearance. ‘Autumn Glory’ was selected for its intense autumn foliage colour, bright gold, and persisting on the tree for many weeks.
Many believe that ‘Autumn Glory’ and the other “digitate” planes are more drought-tolerant than P. x acerifolia, although trees in the Waite Arboretum have shown that “digitate” planes die with significant droughting. “Digitate” planes don’t have woolly leaf undersides that are problematic with P. x acerifolia, and have better branch attachment than many plane trees.
‘Digitata’ (Hillier Nursery Form) planes are probably planes raised from seeds collected in Cyprus, and originally grown in Canberra. These planes have large leaves with spreading lobes and without hairs on the leaf undersides. These planes may be bigger than ‘Autumn Glory’, but their eventual size is unknown. Some arborists believe that ‘Digitata’ planes are inclined to be brittle-wooded, but this has not limited their use in the Melbourne landscape. Mildews and Plane Anthracnose have troubled many P. x acerifolia selections, but ‘Digitata’ appears to be disease-free. Because of the better branch attachment, Metropolitan is growing only the Hillier’s Nursery form of ‘Digitata’. This tree also shows larger leaves than many, and is not likely to be a shrubby, difficult-to-manage tree.
Typical mature height: <18m
Useful in: streetscapes
Sites for best growth: well-drained, occasional irrigation
Spencer, R. 1997 Horticultural flora of south-eastern Australia. Volume 2. University of New South Wales Press.