Weed of the Month: Star-of-Bethlehem
Published May, 2013
Common name: Star-of-Bethlehem
Scientific name: Ornithogalum umbellatum L.
Life Cycle: Perennial
Poisonous: Yes, all parts, especially bulbs and flowers
Star-of-Bethlehem is a cool-season perennial of the lily family. It is native to Europe, but it escaped cultivation. The weed now grows in the eastern half of the United States and portions of the Pacific Northwest. Star-of-Bethlehem grows well in pastures, landscape beds, gardens, fields, and roadsides.
Star-of-Bethlehem grows 10 to 20 inches tall in most pastures and is generally not noted until it reaches maturity. Leaves are narrow with a pale green-to-whitish stripe near the mid-rib. Flowers are showy, with six white petals sporting a noticeable greenish stripe down the middle of the back. Flowering occurs from April to May. The plant dies back to the bulb shortly after flowering. Seeds are small, and seedling plants are rare in North America. Reproduction occurs from bulbs, which grow in clumps and are subtended with a fibrous root system.
Star-of-Bethlehem contains cardiotoxins and glycosides that are toxic to horses. The entire plant contains these toxins, but the bulbs and flowers contain the highest concentrations.
Controlling Star-of-Bethlehem is difficult. Few, if any, pasture herbicides are effective on large, maturing plants. Extremely low mowing (two inches or less) will reduce flower production, but is not effective in killing the plant since it reproduces from bulbs. Paddocks with severe infestations might need to be renovated by killing all vegetation and then seeding grasses. Small patches can be removed by hand or digging the bulbs. Consult your local Cooperative Extension Service personnel for control in your area.
William W. Witt, PhD, a researcher in the Department of Plant and Soil Sciences at the University of Kentucky, provided this information.