SPRING is here and around the Goulburn Valley trees are in full bloom. There is a particular tree however that looks lovely but emits a pungent odour in spring. Often mistaken for cherry blossoms, which smell pleasant, the tree in question is the Pyrus Calleryana, or the Callery pear.
The main street of Tatura is lined with them. In summer, the shining leaves are a lush dark green and very smooth, in autumn the leaves turn shades of yellow, orange, red and bronze and in spring they are flourished with white flowers.
The scent they produce in spring attracts flies to spread their pollen and ward off pollen-stealing insects. These scents are known as ‘volatile amines’, which means they’re molecularly similar to ammonia. In the case of the Callery pear, what you’re smelling is trimethylamine and dimethylamine, which smell similar to ammonia.
The species of tree is native to China and Vietnam and they were commonly planted in new developments in Australia during the 1950s and 1960s due to being remarkably resistant to disease, inexpensive, their appearance and how quickly they grow.
In other countries such as the USA, they are considered an invasive species. Thankfully the scent doesn’t take too long to dissipate as quite soon the blooms will be replaced with the bright green leaves of summer.
