False Gentian
This is a herb cultivated by witches on the Disc. Casual herbalists dismiss it as just another toothache remedy, but in accordance with the Doctrine of Signatures, if you look closely at the cut root by midnight, using a blue magnifying glass, you may be able to read the words GoOD f4r Colds May Cors Drowsiss Do Nit Oprate heavE mashinry
Terrible spelling, but not bad for a daisy, apparently.