Scientific Family
Asteraceae
Plant type
Forbs and Subshrubs
Origin
Native
Lifecycle
Annual
Similar species
Bidens heterosperma
Height
6 to 24 inches
Riparian
No
Slender annuals to 24 inches tall; stems erect, branching above; flower heads small with yellow ray and disc flowers; ray flowers fertile, disc flowers often infertile; outer bracts narrow and green while inner bracts wider, oval with dark parallel lines.
Slender annuals; leaves opposite, 2 bract types differentiate, few narrow outer green bracts, inner are oval shaped, light-colored, dark nerved; ray achenes are oval-shaped, disc achenes narrow, highly divided, 2-barbed like Bidens
Habitat
Found on open rocky slopes, often on volcanic and calcium rich soils.
Plant Community
Pinyon Juniper Woodlands
Montane Conifer Forest
Interior Chaparral
Low elevation
4000
High elevation
7000
Flower Characteristics
Flower heads small, borne singly or loose array; yellow; ray florets 1 to 3 per flower head, disc florets 3 to 10 per head; bracts in 2 distinct series, outer bracts 3 to 5 per head, narrow and green, inner bracts wider with 10 to 15 dark-colored nerves.
Flower color
Yellow
Flower shape
Daisy or dandelion-like
Tubular
No
First bloom month
August
Last bloom month
September
Flower clusters
None
Leaf and Stem Characteristics
Opposite, at least below the flowers; blades 3/4 to 2 inches long; once or twice pinnately lobed, the lobes linear to thread-like, or rarely lance-like, grooved; upper and lower surface smooth; usually hairless but can be densely hairy.
Leaf type
Simple
Leaf color
Green
Leaf shape
Pinnatifid
Leaf margin
Smooth
Leaves clasp
No
Leaf hairs
None
Spines
No
Fruit and Seed Characteristics
Achenes from ray and disc florets have different forms; ray achenes (outer) are oval-shaped and winged, 1/8 to 1/4 inch long and reddish-brown; disc achenes (inner) are narrower and topped with a pair of awns (barbed), up to 1/2 inch long.
Fruit type
Achene