Leafy spurge is a noxious weed of foreign origin that infests over 100,000 acres in Colorado. Leafy spurge is a creeping perennial that reproduces by seed and vegetative buds on the roots. It has an extensive root system with vast nutrient reserves that allow recovery from stresses and control efforts. Leafy spurge displaces grasses and is widespread on recreational and open space lands.
Leafy spurge is 1-3 feet tall, with narrow, strap-like leaves and white milky sap. Flowers are not obvious but are surrounded by a showy yellow-green bract. Mature seeds are expelled several feet from the plant after the seed capsules dry and remain viable in the soil for 8-10 years.
Control requires an integrated approach, using biological, cultural and chemical methods. Four flea beetles of the genus Apthona are available from the Colorado Department of Agriculture Insectary. Adults feed on leafy spurge foliage and larvae on roots resulting in weakened, less-competitive plants.
Sheep and goat grazing can significantly reduce leafy spurge if done during flowering (July) repeatedly over at least 3-5 years. Seed new grasses and avoid overgrazing of existing grasses to provide competition with the leafy spurge.
Herbicide recommendations can be found in the fact sheet 3.107, Leafy Spurge listed below.
For more information, see the following Colorado State University Extension fact sheet(s).
For more information, see the following Planttalk Colorado™ script(s).