Vipers Bugloss (Echium vulgare) is a winter annual or biennial, native to southern Europe. It was introduced into the U.S. as an ornamental. It inhabits grasslands, pastures, roadsides, and disturbed sites. Its presence reduces forage quality and can be toxic to horses and pigs.
Originating as a basal rosette, Vipers Bugloss can grow up to 3 feet tall. Rosette leaves are 2.5 to 10 inches long and 0.5 to 3 inches wide. Rosette leaves are smooth, simple, and lance shaped (and wider towards the tip). Upper leaves are narrowly lance-shaped and are covered with bristly hairs. It has black tap root that can be 12 to 32 inches long. Flowers are blue-purple, and funnel shaped. Vipers Bugloss reproduces solely by seed. Seeds are brown-gray, pyramid shaped with rounded corners, and are very small (less than 0.10 inches in diameter). A single plant can produce about 1800 seeds per year. Seeds can remain viable in the soil for about 3 years. Seeds are dispersed by water, vehicles, livestock, and humans.
Integrated Pest Management (IPM) Options:
• Prevention— Learn to identify this plant. Never transport unknown plant material. Always plant clean seed!
• Mechanical— Hand digging or pulling can be effective on small infestations. Remove as much of the tap root as possible. Remove plants before flowers are produced. If plants have already flowered bag or burn plant material to prevent spreading.
• Cultural— Establish a healthy stand of beneficial plants that will compete for essential resources. Proper grazing management and fertilization can help keep plant communities healthy and less susceptible to weed invasions.
• Biological— None
• Chemical—Metsulfuron (Escort), chlorsulfuron (Telar), 2,4-D LVE, and 2,4-D + triclopyr (crossbow) are a few different herbicide options that may be effective. Ensure that the product you are using is labeled for use on Vipers Bugloss. Always read and follow herbicide label directions!
Justin Hatch, University of Idaho Extension Agriculture Educator in Caribou County. 208-547-3205 JLHatch@uidaho.edu