Stellaria media, Chickweed is native to Europe and obtained its name from the fact that chickens like to eat it.
Chickweed is high in Vitamin C and is used against skin diseases like mange, but also against pulmonary infection and arthritis pain.
It's very popular among rabbits, guinea pigs, and chinchillas.
It's an annual flowering plant in the carnation family Caryophyllaceae. It is even used as a leaf vegetable, often raw in salads. It is one of the ingredients of the symbolic dish consumed in the Japanese spring-time festival, Nanakusa-no-sekku.