Request: Do you know of any archaeological research on the domestication of tea?

One of my graduate students has an interest in tea. I have not had much success in finding articles that offer primary archaeological data on the origin and domestication of tea. It is such an important crop that the apparent lack of literature seems odd. If you can share with me any references or articles, I'd be grateful. If the lack of research is not merely apparent but real, then perhaps the topic merits more study.

Thanks!