Greater Celandine (Chelidonium majus), fam. Papaveraceae.
Grows in the city and in the forest ubiquitously, though never occurs far from roads, and especially likes waste heaps. Blooms starting from the end of April, the flowers having very weak but pleasant smell. In summer, greater celandine fades somewhat and is lost behind other plants, but by the end of autumn and in snowless periods of winter it is without a rival – so unusually bright green it is. The yellow latex is released from any broken part of the plant, the thicker – the more intensively. This latex determines the bitter, acrid and toxic properties of the plant. Greater celandine is used externally to "burn" the undesirable formations on the skin (though garlic, and especially liquid nitrogen are more potent agents for that). Internally, it is only used in strictly defined small doses.