Melilotus officinalis, also known as yellow sweet clover and sweet clover, is an herb that led to the creation of the drug warfarin, used today as an anticoagulant. In herbal medicine it has been used in the treatment of hemorrhoids, lymphatic drainage of congestion, thrombophlebitis and varicose veins, and it also is said to improve blood circulation. The herb also has been used as a laxative and diuretic. Asthmatics have smoked it and it has been used as a poultice in the treatment of rheumatism, wounds and inflammation. As a tea, melilotus officinalis has been used to ease muscle aches, headaches and gastrointestinal problems.
The herb has a number of different names, including field millet, ribbed millet, melilot trefoils, yellow melilot, ribbed melilot and common melilot. In Tudor times in England, the herb was referred to as King’s clover because Henry VIII was known to make use of the herb. Farmers of the day disliked the clover because it became invasive in their pastures and harmed some of their crops. In modern times melilotus officinalis has been planted to avert erosion and increase the amount of nitrogen in soil. Honeybees are fond of melilotus officinalis and it is sometimes planted in pastures for them.
The herb can have side effects, and these include bruising or bleeding, yellowed skin or eyes, mood changes, headache, stomach pain and darkened urine. People with liver disease should check with their doctors before using this herb, and diabetics also should take precautions. Melilotus officinalis should not be used by pregnant women, and a doctor should be consulted when breastfeeding. A blood-thinning compound found in the herb led to its use in mouse and rat poison.
Some birds like melilotus officinalis as a food source and as cover, including numerous kinds of quail, the ring-necked pheasant, the gray partridge and the greater prairie chicken. Small mammals also use the plant for cover and as food. Butterflies, like bees, also are drawn to this plant. Deer, elk and antelope enjoy eating the stems and leaves.