Pineapple Weed
Disc Mayweed
Matricaria discoidea
(Chamomilla sueveolens
Matricaria matricarioides)
Photographed at Mesquite Wash, Maricopa Co., Arizona. April 2008.
ANNUAL: Medium-sized annual of spring time in the Sonoran Desert. Few
plants exceed ½ meter in
height with many stems branching from near base.
FLOWERS: Numerous small yellow disc flowers arranged conically and
without rays. The effect is that the flower heads look like yellow buttons.
Opening March to May.
LEAVES: Smooth leaves are
pinnately divided into narrow segments. On crushing they sometimes emit
pineapple or chamomile aroma. Some plants have little or no such aroma.
RANGE: Requires a good supply of moisture and so is typically found in
riparian habitats or near recently flooded wash channels. More likely in upland
Sonoran Desert.
FRUIT: Small seeds topped with papery scales.
UNARMED. Lacks spines/thorns.