Kashmiri name of P.avinculare is "Drab". Walter R Lawrence in his book "The Valley of Kashmir" (page 72)has made the following
remark . " Drab (Polygonum sp.) is eaten boiled with milk." I tasted the leaves and found that they were not bitter. Thus the assertion that the herb "rau dang" (literally bitter herb} of Vietnam is P.avinculare is wrong. Rau dang most probably is Bacopa monnieri (Brahmi) which is bitter as rightly asserted by a supplier on his website. With the easy availability of commercially cultivated vegetables Drab is no longer used as a food in Kashmir.