What Makes the Smell of Freshly Cut Grass So Good?

What Makes the Smell of Freshly Cut Grass So Good?

If you are one of those who like the smell of freshly cut grass, you are definitely not alone. The result of Dailymail’s research with 2000 people in the UK shows that the smell of freshly cut grass is the third most liked scent.

So what makes this fragrance so special?

Hearing the Death Cry

This smell is actually the smell of a chemical that the grass releases to protect itself when we damage the lawn. This is a chemical aid and even a death cry for grass. It tries to reduce the effect of the trauma experienced by this smell.

Plants are living things that communicate with each other. Just because they’re stationary throughout the day doesn’t mean they can’t be stressed out. Every living thing releases various chemicals to survive in a moment of fear. However, the perception of these chemicals differs from living thing to living thing. We inhale the scent of freshly cut grass and say, “Oh, it smells good!” but it is actually the lament of the surrounding plants for their lost friends.

Yes, it’s a bit of a sad idea, but unfortunately, that’s the way things are.

Green Leaf Essentials

When a plant is damaged, carbon-based chemicals are released into the air. These released chemicals are called “ green leaf volatiles ”. They often release this stimulating chemical not only against lawnmowers but also against insects or infections. In fact, this fragrant chemical is secreted constantly, albeit in small amounts. However, it is secreted much more under stress and we easily perceive it.

Unfortunately, the smell of these chemicals is not just sweet to us. According to research by botanists Baldwin and Allmann , the predatory Geocoris insects are also very successful at detecting this scent. That is, insects can detect “green leaf volatiles”, which we perceive as grass odor, as a signal of a sweet snack nearby.

Not Specific to Grass!

We, humans, do not eat grass, even if we like the smell of grass. However, the “green leaf volatiles” that cause this odor is found in certain amounts not only in grass but also in many fresh green vegetables. Evolutionary reasons lie behind this chemical’s appeal to us. Botanist Baldwin, who says that mature plants can release these chemicals, states that this helps us to understand that the plant has matured, throughout our evolutionary history.

Baldwin also says that this scent is not specific to grass. The “green leaf volatiles” found in almost all plants also cause the same odor. However, as many plants are damaged at once during mowing, the amount of odor produced increases significantly. Baldwin states that the same scent can be detected during the tea harvest.

Warning Mechanism

As we mentioned in the article “Do Trees Talk?“, plants actually secrete this chemical to warn neighboring plants. The neighbor species that receives this message is trying to avoid the possible attack with minimum damage by taking various precautions. For example, after receiving the message, it delivers the sugar in the leaves and other useful resources to more difficult-to-reach areas such as the root. After the danger has passed, it returns to its original state.

Germicidal Effect

In addition, this chemical not only warns those around but also facilitates the healing of the damaged plant. Studies have also shown that “green leaf volatiles” have a germicidal effect.

Baldwin states that this warning mechanism, called Bunkering, is activated within a few minutes. So, after you start mowing, we can say that more resistant grass is waiting in the far corner of your garden that knows you are coming.

References and Further Readings

Green leaf volatiles. (2021, January 02). Retrieved February 27, 2021, from https://en.wikipedia.org/wiki/Green_leaf_volatiles

Grunbaum, M. (2019, May 05). Why does freshly cut grass smell so nice? Retrieved February 27, 2021, from https://www.livescience.com/65400-why-freshly-cut-grass-smells-good.html#:~:text=Chemically%20speaking%2C%20that%20classic%20lawn,forces%20%E2%80%94%20like%20a%20lawn%20mower.

Reporter, M. (2015, May 25). Our top 50 favourite smells revealed (and the 20 worst). Retrieved February 27, 2021, from https://www.dailymail.co.uk/news/article-3096334/Our-50-favourite-smells-revealed-20-worst.html

Scala, A., Allmann, S., Mirabella, R., Haring, M. A., & Schuurink, R. C. (2013). Green leaf volatiles: a plant’s multifunctional weapon against herbivores and pathogens. International journal of molecular sciences, 14(9), 17781–17811. https://doi.org/10.3390/ijms140917781

You can access the sources of the images used by clicking on the images.

The proofreading has been done by Asu Pelin Akköse and Mete Esencan.