In the beginning
Prior to 1848 the common perception in the West was that black tea and green tea were produced from different plants. So, the Royal Horticultural Society, with the support of the East India Company sent Scottish botanist Robert Fortune to locate the black tea plant, steal seeds and samples and bring them to India. Fortune succeeded in obtaining the samples he sought and in the process learned that green tea and black tea came from the same plant; the difference lay not in biology but in processing.
The plant in question is camellia sinensis. Camellia sinensis, is a species within the genus camellia which is part of the family theaceae. Originally the species was called thea, but in 1818 all plants categorized as thea were transferred to the genus camellia. In the mid-19th century, J.W. Masters determined that there were in fact two principal varieties of camellia sinensis, the small-leafed camllia sinensis v. sinensis (meaning from China) and the large-leafed camellia sinensis v. assamica (which is a reference to the Assam region in India.)
Ah, the Home Life
These two varieties were domesticated at different times and, in fact, there likely were several independent domestication events. It is now fairly widely held (outside of China) that camellia sinensis originated in an area known to anthropologists as Zomia. In addition to what is now southwest China, Zomia included what is now the northern portions of Vietnam, Laos, Thailand and Myanmar (Burma.) Scientists have not yet pinpointed when the species divided into two varieties but the estimates are in the tens of millions of years. In any event v. sinensis and v. assamica certainly were domesticated at different times and in different locations.
The Golden Thread
So, in China, botanists learned, all tea was made from camellia sinensis and mostly v. sinensis at that. V assamica on the other hand, was the primary material used in Yunnan province and in India. It is also the most widely planted variety being cultivated in the tea plantations of India, Africa and South America. And now that it was known that green tea and black tea could be made from the same plant, the view developed that all tea comes from the species camellia sinensis. And this view is now the common wisdom of tea lovers, growers and others in the industry.
The most recent statement of this position that I have seen is in Max Falkowicz’s otherwise intriguing article on the development of the market tea in America. I contend, however, that this view is a myth; one that ignores both history and modern developments.
I have mentioned that tea was domesticated in Zomia; it was also domesticated on the island of what is now the country of Taiwan. Records of Taiwanese aboriginals trading in tea with the Dutch date back to the 17th century. But was the leaf that they traded from the camellia sinensis species? Recent scientific studies undertaken in Taiwan by the Tea Research and Extension Station (TRES) show that it was not. Rather, the analysis of the plant DNA provides clear evidence that the Taiwanese trees are not camellia sinensis but a different species which has been named camellia formosensis. Camellia formosensis also has been hybridized with camellia sinensis plants to produce the justly famous cultivar TTES #18, or Ruby Black. Additionally, TRES has announced a new cultivar bred entirely from camellia formosensis material.
Let’s now look at the tea produced in the region of Zomia. For ease I will refer to all such tea as pu’er.
Pu’er certainly is produced largely from v. assamica leaf material. But is has long been known, and conveniently overlooked, that the species camellia taliensis and camellia irrawadiensis have, for millennia, been used in the manufacture of pu’er.
The Shape of Pretzels
Tea is not made exclusively from leaves of the camellia siniensis species. To argue otherwise requires one to argue that much pu’er as well as product produced from Ruby Black is not tea. And such a position flies in the face both of conventional use and common sense. It smacks of a desperate attempt to force the square peg into the round hole. The most we can argue at this point is that all tea appears to come from plants of the genus camellia.
That’s my take. What’s your view?
 Rose, Sarah For All the Tea in China (New York, Penguin Books, 2011)
 Ibid. Rose’s account is a considerably sanitized version of events.
 Green tea, it turned out, was produced from unoxidized leaves whereas black tea was from highly oxidized leaves.
 See https://www.nature.com/articles/d41586-019-00395-4?fbclid=IwAR3sYuuPpljbVwssbDhCh4CH9Huuly8ekepg-KCiYgFjSbS2sUkM2Nln_3s and https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4878758/?fbclid=IwAR0IBopV4MrIdvu-dAgBoJf14JfrdRmbsnyGuSmCDbCFfdzw0IzKqpmbcOM)
 Scott, James C. The Art of Not Being Governed (New Haven, Yale University Press, 2010
 My own view, based solely on reading, is that v. sinensis was domesticated in the area of what is now Sichuan province in China and that v.assamica was domesticated in Zomia.
 Falkowicz, Max “There’s a Reason Americans Don’t Like Tea” https://heated.medium.com/our-american-lifestyle-is-not-tea-friendly-42944bb7ad4a
 See, Hu CY, Tsai YZ, Lin SF (2005) “Using ISSR DNA markers to evaluate genetic diversity of tea germplasm in Taiwan.” J Agri Assoc China 6(5):463–480
 TTES #18 has a Burmese Assam male parent and a camellia formosensis female parent.
 Herbal blends generally are not considered “true” tea but they share the fact of being infused drinks.