viper's bugloss

Viper’s bugloss is a Class B Weed. In regions where a Class B species is already abundant, control is decided at the local level, with containment as the primary goal.

Viper’s bugloss (Echium Vulgare L.), originating from Eurasia, is a biennial that rep roduces by seed. This invasive plant develops a long, stout taproot that can exceed 2 feet in length. During this weed’s first year it forms a rosette; the second year it bolts and produces flowering stems. Stems are erect and branching and reach about 2½ feet in height. The entire plant is hairy. The stems are covered with two types of hair: stout, spreading hairs with a pustulate base marked by a conspicuous dark fleck, and an underlayer of smaller fine hairs. Stem leaves are alternate, oblong to linear-lanceolate, and progressively smaller up the stem. Leaves have white 'speckles' that give the leaves a dimpled appearance. Flowers are funnel-shaped, 5-petalled, and appear in tapering spike-like heads of bright blue to purple flowers. Flowering occurs from late spring to early fall.

Rosette
rosette

Mature Plant
mature plant

Flower Stem

bugloss seeds This species is best not touched as skin irritation can result from the plant’s bristles. Also, this noxious weed is considered poisonous. It contains pyrrolizidine alkaloids that are potentially toxic to livestock, although it is generally unpalatable and can displace desirable grazing plants, particularly if overgrazing occurs.
Seeds
Viper’s bugloss is commonly found in pastures and rangelands, along roadsides, and in disturbed and waste areas.

Physical/Mechanical: Viper’s bugloss can be handpulled if the soil allows for removal of the taproot, but long sleeves and gloves should be worn to guard against skin irritation. Repeated defoliation by mowing can deplete root reserves and prevent flowering, although the plant can resprout from cut stems.

Chemical: Herbicides can be used to control viper’s bugloss. Chemicals that have been effectively used include 2,4-D, metsulfuron and 2,4-D plus dicamba applied to rosettes or bolting plants.

Refer to the label for all herbicides
Always follow label directions prior to use

Biological: No biological agents for viper’s bugloss control have been authorized for release in the United States, although five potential bioagents are currently being studied.