Prickly
lettuce is a summer annual – germinates in the spring. It originates
from Europe and is found throughout the high plains of Colorado. Flowers
are yellow ray florets with a dark blue stripe on the lower side. Leaves
are stiff bristles along the bottom midrib and are 5 to 30 centimeters
long. Prickly lettuce reproduces by seed, so when managing this plant
be sure to get to it before it flowers. This plant can be easily hand-pulled
as a management option.