A biennial Eurasian plant (Echium vulgare) naturalized as a weed in eastern North America and achieving often blue flowers.
a coarse prickly European grass (Echium vulgare) with spikes of blue flowers; naturalized within the U. S.
The viper's bugloss, Echium vulgare, a foreign weed with showy blue plants which has been introduced in to the US.
A cæsal piniaceous plant, Hoffmanseggia stricta, introduced from Mexico into Texas in alkali grounds and considered to be a pest, though its tubers tend to be consumed by hogs and its own foliage, in dry months, by cattle. This is the camote del raton of the Mexicans.
a coarse prickly European weed with surges of blue plants; naturalized in US