THIS SPRING, NEW Yorkers will have their noses assaulted by an unpleasant odour coming from the army of white-blossom covered trees that line many of the city’s streets.
The raunchy-smelling flowers come from the Bradford Pear tree. Their scientific name is Pyrus calleryana.
The trees were planted all throughout New York in the 1960s because they are hard to kill — they grow fast and can thrive in tough conditions. People also think they are pretty. In the eastern United States, they are considered an invasive species because of their prevalence.
The downside, we have learned, is that these hardy “street trees” really stink.
Urban Dictionary has labelled Bradford Pears the “semen tree,” with an equally inappropriate, though colourful, description of their smell, which you can read over there.
Everything we smell — from bananas to pine needles — comes from molecules, usually made of volatile chemicals, meaning chemicals that evaporate easily. The molecules evaporate from the food or flower and travel into your nose, where they bind with receptors in our nose.
The compounds that make the Bradford Pear tree’s flowers smell are likely due to a type of chemical called amines, Dr Eloy Rodriguez, a professor of plant biology at Cornell University, told Business Insider.
We come in contact with the smell of amines every day in the form of body odours, like under the arm pits.
Pretty, but smelly. (Pic: Janice Waltzer/Flickr)
The fishy odour produced by the Bradford Pear is likely a combination of two amines called trimethylamine and dimethylamine, according to Richard Banick, a botanical manager at Bell Flavors and Fragrances. Although perfumers know what chemicals produce the fishy smell (trimethylamine is often used an indicator of how fresh a fish is) they can’t be certain what causes the odour of the Bradford Pear, said Banick.
Later, the trees produce little green-yellow fruits that you cannot eat.
So there you have it. The reason New York City smells like one big orgy starting in April is due to little white flowers that produce a scent, which is apparently inviting to other insects.
- Dina Spector