The summer's flower is to the summer sweet, Though to itself it only live and die; But if that flower with base infection meet, The basest weed outbraves his dignity: For sweetest things turn sourest by their deeds; Lilies that fester smell far worse than weeds.

And to thy sons the plague disastrous brought; Quick through thy walls the foul infection spread, And thou became the city of the dead.

This first stage never infects a young seedling direct, but gives rise to secondary spores, or sporida, from which infection threads may arise and penetrate the shoot of a young seedling and reach the growing point.