What is the name of a vegetable that has no roots and is particularly dark when lying on the ground?

In the supermarket, there is a kind of vegetable lying on the ground without roots. It's called shepherd's purse. Shepherd's purse Shepherd's purse is a kind of wild vegetable, which is delicious and can be used as jiaozi, Mala Tang and so on. It has many uses and grows in fields, roadsides and gardens. Feeding on young leaves has high nutritional value, diverse eating methods and high medicinal value.