And The 2008 People's Republic of China National Standard (GB/T 22111) winner is:
Camellia sinensis var. assamica
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I first postulated this when I tasted a similar earthiness between a certain Arabic Assam which tasted fermented and Shu which I didnt notice in other fermented teas. Ive seen video of the Indian monsoons in the Assam Valley viewed from the Himalayas and couldnt help but thinking seeds were probably blown over the top. It doesnt say it but it is regarded the planted terraces known as small leaf are Camellia sinensis var. sinensis. I still would think the terraces are cloned assamica which is how the Charleston tea plantation was produced.
Jim