by Lauren Umek
Summer in Chicago is filled with a rich bouquet of smells, some desirable, others less so. A few of those delightful smells, those not from the grill, that is, are from inconspicuous bits of nature. In this post, I attempt to channel my inner nature sommelier and describe a few key smells that tickle your olfactory neurons this month.
The sweet, floral smell that you’ll find while driving, walking on the sidewalk, or strolling in a park, but away from the flower beds emanate from summer flowering tree Tilia americana more commonly referred to as Linden or Basswood trees. These trees have relatively small un-assuming flowers that dangle from the trees that are planted throughout Chicago’s parks and parkways. The flowers, sometimes used for herbal remedies have a sweet smell, that attracts bees and flies for day time pollination. The smell tends to get stronger at night, attractive nocturnal moth pollinators, so be sure to enjoy this smell on an evening stroll.
The rotten/sweet smell that you’ll detect in odd places is likely a result of the weedy and messy, yet tasty mulberry Morus nigra. The tree is content to grow in sidewalk cracks, alley ways and seemingly any pocket of unoccupied ground. You might not immediately see the tree, but the fruit, an urban wildlife favorite, is regularly splattered on sidewalks and often smells from a distance.
My favorite of the summer smells is that smell associated with a rainstorm, and only in part because it is due to soil microbes. After a rainstorm, the earthy smell comes from a type of filamentous bacteria called Actinomycetes. These bacteria, which are also important for decomposition in soils, reproduce via air born spores. With rainfall, water droplets kick up these microscope spores into the air, and thus into our nostrils.