Leafy spurge (Euphorbia esula) is a perennial that grows up to 3 feet tall with yellowish green flowers arranged in heart-shaped clusters. This species has been reported to cause severe irritation of the mouth and digestive tract in cattle which may result in death.
The roots can extend as deep as 30 feet into the soil and are extremely wide-spreading. The roots are brown and contain numerous pink buds that generally produce new shoots or roots. The entire plant contains white, milky sap that exudes readily upon stem or leaf breakage. This sap can damage eyes and sensitive skin. Leafy spurge is one of the earliest plants to emerge in the spring. Flower clusters develop 1 to 2 weeks after stem emergence in mid-April to late May. One plant can produce up to 130,000 seeds and the seed capsules explode when ripe, projecting seeds up to 15 feet away.
Leafy Spurge Management
Cultural: The most effective method of control is to prevent its establishment through proper land management. Maintain healthy pastures and rangeland and continually monitor for new infestations.
Biological: Both sheep and goats can be effective grazers of leafy spurge. The flea beetles (Apthona nigriscutis, A. lacertosa, and A. cyparissiae) are effective when combined with grazing and herbicides.
Mechanical: Due to extension root systems, hand pulling is not a viable option. Mowing repeated every 2-4 weeks during the growing season will reduce seed production, but will provide little long-term control.
Herbicides: Application of herbicides should coincide with plant maturation. Certain herbicides are effective during the spring only during bloom to post bloom stage. Other herbicides should be applied in the fall prior to hard freeze.
Consult your local weed board for more information.