Characteristics:
Long prickly-headed poppy is an European species that has escaped from cultivation. It is an erect annual from 15-50 cm high, with stiff-haired herbage. The leaves are twice pinnatifid and dissected.
The flower buds nod, but become erect on flowering. The bristly sepals are 5-10 mm long while the obovate petals are 1.5-2.2 cm long. The petals are scarlet with a blackish base. The seed capsule is narrow and from 1.5-2 cm long, prominently ribbed with stiff bristles (see photo above).
Long prickly-headed poppy is found cultivated in fields, and may be seen growing occasionally in disturbed areas or along roadsides.
Papaver argemone is a native of Europe, and may be found in scattered locations east of the Cascade Mts. in Washington.
In the Columbia River Gorge, it may occasionally be found east of Wind Mt. from 100'-2200' in elevation.