I watched with unabated horror as the uniformed caretaker clambered down from the topmost rung of his fold-up ladder, industrial scissors in hand, and began motioning for the drove of onlookers to disperse. His crowd was mostly salt-and-pepper haired housewives of fifty, clucking scandalously among themselves and gazing at the tree - violated, like many others before it - and left threadbare. Normally, the bystanders would have been diving to their knees by now, plucking pungent ginkgo biloba berries from the ground, as the caretaker shook out the full, yellowed stalks of the tree overhead for the berries to rain vigorously with rhythmic tot-tot-totters, methodical taps on the ground as they fell and rolled. Instead, the caretaker had taken his scissors and snipped the branches from a greening ginkgo tree. The tree looked like a windswept, vandalized stump, its leaves sliced off and half-formed berries smouldering on the sidewalks. I felt my throat clam.

Around the time when Seoul was still a largely plantless hellscape of steel lumbar and gunmetal grey concrete, botanists had no idea how to pre-determine the gender of a ginkgo tree before it was planted. Ginkgos had already been delegated as the ideal species of urban sidewalk tree. They had high internal resistance levels to pollution, beautiful egg yolk-yellow coloring in the autumn, and excellent built-in processing abilities for waste and CO2 that would contribute positively towards the city’s polluted atmosphere. So, the city-planners of Seoul, South Korea, took ginkgos - both male and female - and planted them along many, many sidewalks in the city. The results were polarized, but definitely favorable. On the one (significantly heavier) hand, ginkgos were beautiful, hardy, and tenacious floral companions that made for stunning shots of the pedestrian cityscape - tender and coming alive with shoots in the spring, intensely green and acting as cicadas’ footholds in the summer, yellow and carpeting the roads with leaves in the fall, and bare-chested and haughty against the greying sky in the winter. Everyone’s phone galleries were bursting with selfies. 

The only problem? The girl-trees kept producing fruit.

Ginkgo is a dioecious species, which means that male and female flowers are borne on separate ‘genders’ of trees. Female trees bear cherry-sized fruit of yellowish-orange coloring, the hard ‘nut’ (rather like a mini pistachio) inside protected by a squishy outside layer that produces an unpleasant odor when crushed. Imagine a cherry, but the flesh of the fruit is actually inside the seed (which cracks open when cooked, like a clam) and the delicious cherry part of the fruit is a smelly, moist protective layer. These fruits were produced in extremely large quantities by the female trees, and caused odour problems in the autumn due to being dropped on the sidewalks (they are completely harmless attached to the boughs) that the city sought to combat, but to little avail.

Hence the apartment-wide mandate of simply chopping through the limbs of all growing ginkgo bilobas. People were heartbroken for many different reasons. For people like my mother it was seeing the trees so barren and dead, like they’d been struck by bolts of extremely selective lightning that ninja-sliced through all their appendages and left them like gruesome hacked torsos. For others it was the ruined prospect of a good fall harvest - many people liked to take black plastic bagfulls of ginkgo berries home, suffer through the interminable smell while washing them in the kitchen sink, then microwave the seeds in milk cartons until they came out browned and hot and delicious. And still for me they were a source of intense scientific curiosity - had nobody yet figured out how to differentiate the gender before planting, so that the girl trees could be sent to ginkgo farmers and the boys could be planted, seedless and stenchless, and grace the sidewalks with only their faberge-yolk leaves without the baggage?

As it turns out, in 2014, South Korea’s botanists patented a method that allowed for them to discern the gender of a ginkgo from nothing more than a leaf the size of a fingernail from a one-year old sapling. The method went on to receive an international patent in 2015 in China, the original birthplace of the ginkgo, and was commended for its ingenuity by placing gold at the 2019 Seoul International Inventions Expo. 

In 2018, in order to combat the proliferation of female ginkgos, the National Institute of Forest Science (NIFoS) exported the identification technology to 4 private companies in the hopes that the expedited time period of identifying seedlings' genders will help all-male plantings occur in the future. A NIFoS representative said that “Ginkgo trees are forest life resources of high value as street trees, landscaping trees, food, or medicinal resources, and will be planted extensively during the spring planting period this year.” He went on to advocate the expansion of ginkgo identification technology, calling upon individuals to "Please expand the transfer of ginkgo gender identification technology to create pleasant autumn streets and use them actively in the future”.

So the time has come to bid farewell to acrid autumn streets, replete with yellow leaves and ginkgo berries and the familiar aroma of crushed biloba flesh. Instead, technological advancement has paved the way to a more pleasant pedestrian experience of Seoul's autumn. May the yellow lungs of Seoul's fine dust-laden airspace go on to enjoy a long and happy life looking down on the tops of our heads for years to come.