Now for a couple of rarities.
The first I have only seen fresh once, far from here, so no picture. But I can get it easily preserved and bottled. It is well-known in China.
Brasenia schreberi
Water-shield. In Chinese 莼菜/蓴菜 (Mand: chún cài). I have failed to find the Cantonese. What do they know?
(Please note: this is a different species than Carolina water-shield.)
This aquatic plant grows world wide, but so far as I know only the Chinese and Japanese eat it. I'm probably wrong. It is somewhat mucilaginous which may put some people off.
Ask anyone in China about it and they will all reply "西湖莼菜汤 (Mand: xī hú chún cài tāng)". This is West Lake Water-shield Soup", one of China's most famous dishes, originating from Hangzhou in eastern China where one finds the West Lake in which the plant grows. That is where I saw it fresh. The soup is usually made from beef and water-shield.
I have never seen any other recipe which uses it.
The next is even rarer.