Have you ever wondered why city boulevards are dominated by male Ginkgo biloba trees? My first field encounter with a female Ginkgo biloba specimen only happened last summer and I wondered why that was.
It turns out the females produce seeds in a fleshy covering (the sarcotesta) which contains butyric acid. Once fallen on the ground the fleshy parts produce an unpleasant odour; not exactly the best thing for city boulevards. I have seen various descriptions of the smell but why not find out for yourself? If you can find a female Ginkgo.