Is Dragon well (Lung Ching / Long Jing) just a style of tea or is it wedded to a particular region, like Pu-erh? (Pu-erh is named after a county; technically, the style of Pu-erh could be called hei cha--"black" tea, or post-fermented tea). I think it is ultimately good for tea producers and for the interest of sustainability and promoting and preserving local tea cultures to distinguish the notion of style and region in order to allow the non-controversial marketing, distribution, sampling, and purchase of teas of one style produced in many different regions.
Dragon Well originated in Zhejiang province, whose location is shown on the map below: (public domain image from Wikipedia, thanks to Joowwww).
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But, as Gingko and many others have pointed out, you can find tea labeled as Dragon well from other provinces as well. Also, within Zhejiang, dragon well is produced in many different areas. According to Gingko's post, the tea produced in Hangzhou has been considered more desirable over the years.
What is "authentic"?
I think it can be problematic to say that a tea of one style produced in a different region is not "authentic". If the name of a tea refers to the style and not the region, such a label is incorrect. Is Vietnamese Sencha not sencha? What about Tie Guan Yin from Nantou? Or Ceylon Young Hyson? These are all examples I've tried...and I picked them because I all think they are outstanding teas...and they are all radically different from their counterparts from the original regions that produced these styles.
I love tasting how the aroma and flavor varies across different regions, even for tea produced according to the same or similar processes. I think that being able to make these comparisons is good both for preserving local tea traditions and for encouraging the creation of new ones. I also think that it improves people's sophistication...fitting in with the whole premise of the slow food movement, something I have been becoming more a fan of lately.
I think the ideal way to handle these things is to draw attention to where each style originated, but, except in the cases where the name refers directly to a region (such as Pu-erh) to refrain from judgments or value-statements like "authentic" or "fake". A term like "original" is a lot more descriptive. The naming scheme for some Chinese teas already incorporates both style and region. For example, mao feng green tea is grown in different regions; Huang shan mao feng is mao feng from yellow mountain in Anhui, whereas Wuyi mao feng is tea produced in the same style from the Wuyi mountains, and Ilam mao feng is produced in Ilam, Nepal.
How do Shoppers React to Accusations of "Fake" Teas?
Everyone is different, so I can't predict others' responses, but I can at least share how I react. When I read writing on a tea company website that makes disparaging comments about teas from other provinces, my first reaction is skepticism. One question immediately pops into my head: "Why do these people have a bone to pick?"
It is obvious that the vendors of tea from the original region feel threatened by similar products from other regions. But why respond with negativity? Negativity shows weakness and a lack of confidence. If they want to make their product stand out, though, they can do so by one simple method: push for accurate labelling of place of production. If a certain region is superior, and labelling is accurate, people will soon realize this and the producers in this region will be secure. Throwing around disparaging comments about teas being "fake" just because they originated in a different region communicates that the seller feels threatened--which communicates that, deep down, they are worried that their product might not be superior as they claim. Why send this message? All it will do is make fewer people want to buy the product.
I think a more positive response is that which Gingko has taken--put more information out there about the tea. I also think that, by questioning the notion that Hangzhou Dragon Well is necessarily superior, and pointing out that many tasters cannot correctly identify the region of production, Gingko demonstrates a critical mind--which immediately cuts through the B.S. and talking up of their product that some tea companies are guilty of. At least as far as I'm concerned, this makes me feel more comfortable buying a product.
So why talk up your product? Just put accurate info out there and it'll speak for itself!