Why did only poppys grow in World War 1 fields?

During World War I, the intense trench warfare and the use of heavy artillery devastated the landscapes of the battlefields, causing soil disturbance and killing off existing vegetation. Poppies, particularly the common field poppy (Papaver rhoeas), are hardy and can thrive in disturbed soils, where they were able to flourish in the wake of destruction. The bright red flowers became symbolic of the bloodshed and sacrifice of soldiers, leading to their association with remembrance of those who died in the war. This phenomenon is often celebrated in the context of Remembrance Day and memorial events.