In 2012, news was released about a new farming site discovered in Munam-ri, Goseong, Gangwon Province, South Korea, which may be the earliest farmland known to date in east Asia. "No remains of an agricultural field from the Neolithic period have been found in any East Asian country before, the institute said, adding that the discovery reveals that the history of agricultural cultivation at least began during the period on the Korean Peninsula". The farm was dated between 3600 and 3000 B.C. Pottery, stone projectile points, and possible houses were also found. "In 2002, researchers discovered prehistoric earthenware, jade earrings, among other items in the area". The research team will perform accelerator mass spectrometry (AMS) dating to retrieve a more precise date for the site.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): When did researchers discover prehistoric plants?
unanswerable