Gayle Licari wrote in a message to Alex Vasauskas:
 GL> Does St. John's Wort have tannin properties?  I have noticed a
 GL> persimmon like taste or after taste after taking the prescribed
 GL> doses. Gayle 
Although SJW is astringent, which is characteristic of tannins,
my references do not indicate that it contains tannins.
I don't know that I would describe the sensation of astringency
as involving a taste but rather a sensation of drying in the
mouth or throat.  It is the feeling you get in the back of the
mouth and throat when drinking very strong black tea or crampbark
decoction.  Externally, you get this feeling when applying something
like witch hazel to the skin.
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