Lactuca biennis (Moench) Fernald
Family: Asteraceae
tall blue lettuce, woodland lettuce
Lactuca biennis image
Merel R. Black  
Etymology: Lactuca: name for "milk"
Plants: erect, annual/biennial, 2' -6 1/2' tall, mostly smooth forb with milky juice; stems very leafy
Leaves: either pinnately-divided or toothed, sometimes with arrow-shaped bases
Flowers: head 3/8" wide with 15-34 bluish to white rays; inflorescence with many heads in long, narrow clusters; blooms July-Sept.
Fruits: dry seed with several obvious lines on both sides, and with tan, fluffy pappus
Habitat: moist; thickets
Conservation Status: Native