Several days ago, I got out of the shower and was drying myself only to realize that Precious Mae’s litter box hadn’t been cleaned recently. I got a bag and cleaned the litterbox, mentally thinking about how distasteful cleaning cat shit and pee out of the litter box is. In my imagination, at least, cleaning the litter box, running the little-slotted shovel through the pile of litter, stirs up a cloud of contaminated dust that settles on everything, especially my slightly damp bare skin. So I got back in the shower to rinse off. The millisecond  I got in, I was flooded with the familiar smell of summer camp. I could see that the shower was wet, I could feel the wet walls and door, but neither of those senses transported to another place and another time like that familiar smell.

Two other familiar smells that I associate with places are the distinctive smell of the Eastern Sierras, especially in the summer and fall, and rain in the desert. But it’s not just rain, as I found out about thirty years ago. A friend and I had gone to Dante’s View to look at the stars, Dante’s View is at an elevation 5,476 feet and in those days there was not much light pollution from Las Vegas so the view of the sky from Dante’s View, on a moonless night, was stellar (sorry). 

As an aside, this was over the Easter Break and we were awakened about 4:30 by a Geology Class from Cal Poly, San Luis Obispo, driving up in about five cars. At first, a bunch of cars driving up in the dark was a little disconcerting because we were sleeping on the ground, right next to the parking lot – which, in those days, was above the current parking lot, on top of the ridge – but we soon learned that they had come to watch the sunrise and get a lecture on the forming of Death Valley. All we had to do was sit up in our sleeping bags to attend the class. It was the only time I listened to a lecture in my sleeping bag. End aside.  

After the lecture, we drove down to Furnace Creek – which is at sea level – and, as we dropped down in elevation, it got hotter. It had been a cold night so we rolled the windows down and opened the sunroof,  soaking in the heat and the view at about 20 miles per hour. We had just turned off of the Furnace Creek Wash Road onto Highway 190, it was probably in the high 80s and there wasn’t a cloud in the sky when we smelled rain. The smell was so strong and so distinctive that we were both shocked. I slowed down and, for a moment, I thought I had popped a radiator hose, but it wasn’t that rubbery smell, it was the distinctive smell of rain in the desert as unlikely as that seemed. Then we turned a corner and there, in front of us, was a huge water truck slowly waddling down Highway 190, water splashing out of the open hatch on top and dribbling down onto the dusty road where it evaporated almost immediately, leaving only that distinctive smell. 

A couple of days ago, I found out that the smell is so distinctive that it even has a name,  petrichor which is defined by Google’s dictionary as a distinctive scent, pleasant or sweet, produced by rainfall on very dry ground. According to Wikipedia,  The term was coined in 1964 by…Isabel Bear and Richard Thomas, for an article in the journal Nature. In the article, the authors describe how the smell derives from an oil exuded by certain plants during dry periods, whereupon it is absorbed by clay-based soils and rocks. During rain, the oil is released into the air along with another compound, geosmin, a metabolic by-product of certain actinobacteria, which is emitted by wet soil, producing the distinctive scent.

The same Wikipedia entry went on to say that the oil retards seed germination and early plant growth. I knew that creosote bushes – Larrea tridentata, if you care – drip poison to stop other plants from growing nearby but I thought it was the only one. Life in the desert is harsh, water is scarce, and it turns out that lots of desert plants do the same thing giving us that familiar and pleasant smell; petrichor.