Brachychiton x turgidulus
This year is being a great year for Brachychitons. Toowoomba is aflame with Flame Trees (B. acerifolius). The large, felty pink flowers of Lacebarks (B. discolor) are looking wonderful where they have been planted along the new England Highway at Highfields, and where they still occasionally occur in the remnants of their natural rainforest habitat at Highfields and Gowrie Junction. Locally native Kurrajongs (B. populneus) are heavily in flower along the roadsides, particularly between Goombungee and Meringandan, where their nodding bells are inconspicuous until you slow down for a closer look. And our other local native brachychitons, the Bottle Trees are displaying their creamy-white flowers. The main street in Goombungee is a good place to look for them. There are also many beautiful Brachychiton hybrids, produced and marketed by those clever people in the horticulture industry, to be seen in gardens of the district.
Less familiar is the naturally occurring hybrid between kurrajongs and bottle trees. It occurs often enough to have been given its own name, Brachychiton x turgidulus, and it occurs in places where its parent trees can be found somewhere nearby. We call it a bottlejong.
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| Bottlejong |
Its flowers take some of the characteristics of their parents. Their redness comes from the kurrajong, but they are usually redder. Compare this photo with the kurrajongs below.
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| Kurrajong. Minimally red. Note the shorter lobes. |
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| Kurrajong, tree 2. Greener flowers, with a red centre. |
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| Kurrajong, tree 3. Strongly red flowers |
The white backs of the Bottlejong,together with their subtle hairiness, come from the bottle tree parent. The flowers of bottle trees also vary naturally a little both in their hairiness and their colour. They can be white or cream, and may have some red speckling..
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| Bottle tree. A very white flower. |
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| A different bottle tree. A hairier flower, with a few red speckles. |
In shape Bottlejongs are part-way between parents, with lobes longer than the kurrajong, but shorter than the bottle tree, in relation to the overall length of the flower. Note also the different colour of the flower back of the hybrid, in relation to its kurrajong parent.
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| Kurrajong. Rounded bell, green on back. |
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| Bottlejong, wider flowers, with whitish, V-shaped back. |
The trunk of the Bottlejong is stouter at the base than the trunk of a true kurrajong (for which it is often mistaken) but not as stout as a bottle tree trunk. "Turgid" means swollen, and it is the wide trunk that distinguishes the hybrid from kurrajong, and has given Brachychiton x turgidulus its name.
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| Wide flowered Kurrajong, Brachychiton x turgidulus |
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| Kurrajong, Brachychiton populneus. Note the straight trunk. |
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| Bottle tree, Brachychiton rupestris. |
Because they are so often mistaken for kurrajongs until they reach the age of flowering, which may take 20 or 30 years, young hybrids go unnoticed. We are uncertain whether their leaf-shape has the same variability as their parents. Like its parents, it usually drops most of its leaves before flowering. In its best flowering years, such as this one, the leaf-drop may be complete, with new leaves coming in as the flowers begin to die.
I only know, personally, of a few of these trees. I have been told that they are quite widespread around Toowoomba and the Darling Downs, however, so would be interested to hear from any readers who are aware of this interesting plant.
