Melampyrum nemorosum
Melampyrum nemorosum is an herbaceous flowering plant in the family Orobanchaceae. It is native to Europe. In Sweden it is called natt och dag. In Russia it is called Ivan-da-Marya. a Christianisation of the traditional Slavic Kupalo-da-Mavka.
This is an annual plant. The new leaves are blue, turning green as they mature. They are usually toothed at the bases.
This plant is a host to the fungus Cronartium flaccidum.
