Prickly Lettuce (Latuca serriola)
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.