In 1921, Frank Schofield determined that cattle haemorrhaging in Canada had eaten mouldy sweet clover hay. The discovery began the chain of research that led to dicoumarol and then warfarin. A farm tragedy thus became one of the most important routes to oral anticoagulant therapy.

The story of Sweet Clover Disease traced to mouldy hay in 1921 has a striking poetic quality: hay, sweetness, mould, cattle, and blood becoming modern medicine. It illustrates how rural observation can transform into a lifesaving drug, inspiring poets to reflect on the interconnectedness of nature, agriculture, and human experience.