The smell of spring brings two distinct odours to mind; flowers and rain. But more specifically, the smell of sperm and the smell of bacteria sperm.
The last house I lived in was in Wellington, a city in New Zealand best known for its wind and it’s hills. My house, like many others in the city, was accessed by a long set of stairs. The stairs were stunningly adorned in twisted branches and lush leaves that formed a natural tunnel , the beauty of which visitors were quick to comment on. The tree that shaped the arched structure was Pyrus calleryana, commonly known as the Callery Pear Tree
Wikipedia description: “Pyrus calleryana: A species native to China and Vietnam, in the family Rosaceae. It is a deciduous tree growing to 5 to 8 m tall, often with a conic to rounded crown. The leaves are oval, 4 to 8 cm long, glossy dark green above, and slightly paler below. The white, five-petaled flowers are about 2 to 2.5 cm in diameter.”
AND IT FUCKING WREAKS OF SEMEN!!
Fortunately though, it only smells this way when it’s flowering, a short period during the beginning of spring. But one thing was for certain, the plants viscous musk was not in vein. For several weeks the huge tree was absolutely buzzing with pollinator activity; butterflies, bees, bumble bees and insects that I’ve never seen before. As an environmentalist, I am an advocate for planting trees that attract bees to your garden, so let’s just say, the Callery Pear tree and I had a love hate relationship.
Fittingly, the tree speaks the language of love, or should I say, it knows the language that’s most likely to get it laid (pollination being the equivalent of plant sex). Paul A. Moore, the author of The Power of Smell explains that some species of flower speak a very specific odour language, aimed at one, or very few, species of pollinators and others, like in this case, speak a more general language that targets as many pollinators as possible.
Conversely, the explanation of the next smell is simply a by-product of sex
An odour so significant to the smellscape of spring is the smell of rain on hot ground. A sneaky sun shower interrupting a long dry spell creating an earthy aroma that I just can’t get enough of.
But the reason why this has anything to do with bacteria sex is that the distinct earthy smell of spring rain is due to bacterial spores being disturbed by falling rain and riding the moisture rich air up into our noses. spores are bacteria’s reproductive mechanism; similar to the mammalian sperm and egg, but yes, a lot of different bacterial spores often make it into our noses, most of which are harmless. The bacteria that causes this specific smell is called actinomycetes, and the spores contain a substance called geosmin that is the specific cause of the smell.
Because these bacteria thrive in wet conditions and produce spores during dry spells, the smell of geosmin is often most pronounced when it rains for the first time in a while, because the largest supply of spores has collected in the soil. Studies have revealed that the human nose is extremely sensitive to geosmin in particular—some people can detect it at concentrations as low as 5 parts per trillion, which is to equivalent to one teaspoon in 200 Olympic size swimming pools.
This sensitivity to the smell might come down to an evolutionary trait telling us when food is coming, some researcher speculate. Spring is a highly productive time for all of nature, and our noses have tuned into the languages of it, whether it be flowers; signalling fruit is on the way or rain signalling plentiful crops and animals. But what I take away from all of this is that sex is good for us.
The Hidden Power of Smell: How Chemicals Influence Our Lives and Behavior By Paul A. Moore
“Geosmin, an Earthy Smelling Substance” – N N Gerber & H A Lechevalier
Young, Diana (2005) The smell of greenness: cultural synaesthesia in the Western Desert. Etnofoor, 18 1: 61-77.