One of my favourite perennial vegetables and a fantastic edimental is Aster scaber (nowadays Doellengeria scabra), here harvested in spring in my garden:
In September, in a farmer’s market in Atlanta, Georgia I found packets of dried Aster scaber leaves (I had searched unsuccessfully for chwinamul in other Korean supermarkets, but hadn’t found it before):
On the front of the packet is a WARNING: This product contains chemicals known to the State of California to cause cancer and birth defects or other reproductive harm!
On the other hand, on the back of the packet it says: “Keep your health with benefits of HAETAE Sangol Hyanggi Namuls”
Is the reason for the cancer warning on the packet due to the fact that the same packet is used for a range of dried vegetables and shiitake mushrooms (namul), including bracken fern which contains a carcinogen, ptaquiloside (however, it is both water-soluble and is destroyed by heat )
I was also surprised to read what would seem to be the excessive pre-preparation by boiling for 20 mins., followed by a soak overnight and then rinsing 7 times, to remove the bitterness. I’ve never detected bitterness and have understood it’s also used in salads. I wonder also why they are known as “thumbs”?