How many trees have red as opposed to yellow autumn foliage? Having written last week about why northern hemisphere trees with red autumn leaves are mostly limited to East Asia and the USA (many red-colouring European trees retreated south during the Ice Ages, bumped into an east-west mountain range and became extinct), I ran out of space before getting down to any actual trees.
I didn’t think my editor would take kindly to a column twice its allocated length, so I’ll try to make up for it today.
Maples are ideal to start with if you’re looking for red leaves in autumn and with about 150 species, including plenty from the USA and Asia, there’s a wide choice.
North American Red Maple (Acer rubrum) is a big tree (20 metres) needing high rainfall to flourish. Hybrids with fiery autumn foliage include “Brandywine”, “October Glory” and “Somerset”.
The smaller Japanese Maples, A. japonicum (5m) and A. palmatum (3-3.5m) have many varieties with brilliant colour but also need moderate to high rainfall.
Box Elder Maple (A. negundo) is weedy in NSW and anyway, has no autumn colour, but its medium size (9m), sterile hybrid “Sensation” has scarlet and orange autumn leaves and thrives in a range of conditions including moderate rainfall.
Trident Maple (A. buergeranum, 6m) is my preferred option for drier districts. It has small, three-lobed leaves, crimson in autumn, though less good after a dry summer. It is quite slow and self-seeds prolifically from an early age.
American Oaks with gorgeous autumn colour include Pin Oak (Quercus palustris), Scarlet Oak (Q. coccinea) and Red Oak (Q. rubra), all big trees up to 25m.
Their leaves are similar, but Scarlet Oaks are easily distinguished by their idiosyncratic habit of turning deep, clear red on one or two branches while the rest of the crown remains green. Eventually the entire tree turns red.
Other North American trees that prefer high rainfall include Tupelo (Nyssa sylvatica, 20m), the well-known Sweetgum (Liquidambar styraciflua, 15m) and the much smaller (5m) Eastern Redbud (Cercis canadensis) of which you need the hybrid “Forest Pansy” for burgundy leaves; the species turns yellow.
North American Red Maple (Acer rubrum) is a big tree (20 metres) needing high rainfall to flourish.
Persian Ironwood (Parrotia persica, 7m) from Western Asia has shiny autumn leaves varying from red and orange to purple and tolerates moderate rainfall.
The Taiwanese Liquidambar, L. formosana, 30m in nature but smaller in cultivation, is better than its American counterpart in drier districts with similarly bright autumn colour.
Two other Chinese trees with red autumn foliage include the easy and reliable Pistacia (P. chinensis, 15m) with pinnate leaves, and the smaller (5m) Disanthus cercidifolius, with heart-shaped leaves similar to Cercis “Forest Pansy” (above).
Autumn is the time to select trees for their colour in nurseries, as you can see exactly what you’re getting.
New England Regional Art Museum’s Autumn Ramble takes place at the weekend of April 1-2, 10am-4.30pm, at Myola garden, 278 Toms Gully Rd, Black Mountain, near Armidale. Sculptures, garden books, plants, produce and other garden attractions, refreshments. Admission is $10, (NERAM Friends $8), www.neram.com.au/