Horseweed
Conyza canadensis

Family: Sunflower (Asteraceae)
AKA:
Photo taken on: August 10, 2009
Location: White Rock, NM
Life Zones: Plains to foothills
Habitat: Disturbed areas

Grows to 4ft with leafy stems. Leaves are long and narrow. Tiny flowers grow in loose clusters. Weedy.

Flora of North America reference.