These are fertile shoots of field horsetail (Equisetum arvense). I didn't expect them to grow in such a busy place close to a waste collection site. (You can see blue plastic bags piled up in the 1st photo.) I've seen fertile shoots of field horsetails many times but only in the field.
They also made me realize that I didn't know what they were at all, i.e., that they're shoots; that they're reproductive stems; and that they're surrounded by their green relatives, i.e., sterile shoots. Such ignorance, however, may not be necessarily all my fault. In Japan, a fertile shoot of field horsetail is called tsukushi, considered (by many) as a different plant from field horsetail, which is called sugina. There's even a children's song in Japan entitled "Whose child is a fertile shoot? It's field horsetail's."