Argemone pinnatisecta (Sacramento Prickly-Poppy)
Robust, herbaceous perennial, with 3-12 branching stems, 0.5-1.5 m tall; leaves blue-green, 10-15 cm long, divided, the sinuses broad and square, margins, midribs, and veins armored with stout yellow spines; stem and leaf latex white; flowers large a...