The Smell of Freshly Cut Grass

By Anupum Pant

Freshly cut grass certainly smells nice, doesn’t it? So does the smell of rain and the musky odor of books. There’s a reason why the freshly cut grass smell feels so good to humans, but first let’s see why does it even exist.

Some incorrectly believe that the freshly cut grass smell is a distress signal for other nearby plants to communicate to them that there’s something, either a plant eating insect or animal, coming towards them and that they need to move their nutrients to the root as soon as possible. That’s not quite right, or that is what science believes. Although there might be some truth to it because these things haven’t been extensively studied due their complexity. Researchers however have a strong feeling that this smell might not even be detectable by other plants.

But that smell, as studies have shown, definitely sends down signals that other insects can react to. This smell that comes from the fatty volatile substances released by plants is in fact really is a distress signal, however not for other plants to detect directly, it serves two purposes.

1. It is a plant’s way of repelling the insect that’s eating it by making itself smell less appetizing to the insect.
2. It’s  also a way for plants to call the parasitic insects to protect them from these plant eating creatures. Parasitic insects like wasps are expected to come and lay eggs inside herbivorous insects like caterpillars. And that ultimately saves the other plants from being eaten.

Another study conducted by Department of Physiology, Osaka City University Graduate School of Medicine says that this odor, composed of a mixture of  trans-2-hexenal and cis-3-hexen-1-ol, both of which can be bought from a chemical supplier, is called green odor and has a psychological effect among apes.

It can in fact heal the psychological damages caused due to stress. The mixture of these two chemicals causes local blood flow in the part of your brain that processes information for you to be able to smell it, obviously. But it also does the same in some other parts which isn’t usually effected by other common smells. That, they think indicates that the smell of freshly cut grass does in fact explains the healing effect. So, it’s good for apes and they like the smell.

It also reduces stress among rats and decreases the sensation of pain to some extent among humans. The smell also does help us tap into deep touching memories too, often referred to as the Proust Effect.

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