Botanical name: Matricaria matricarioides Family: Asteraceae (Sunflower family)
Synonyms: Chamomilla discoidea, Matricaria discoidea, Cotula matricarioides
Pineapple-weed is an annual weed with finely dissected leaves that emit a sweet pineapple-like odor when crushed. It is primarily a weed of landscapes, nurseries, and turfgrass, but also occurs in compacted areas like gravel roads or walkways. Stems arise multiple from base, from taproot, ascending to erect, hairless or with a few sparse hairs, to 15 cm tall, herbaceous. Leaves are alternate, stalkless to very short stalked below, up to 1.5 cm long, 7 mm broad, deeply singly or doubly cut. Ultimate segments are linear, lanate (sparse), green. Inflorescence is a loose cyme-like arrangement of terminal flower heads. Flower-heads are globose to ovoid, up to 8 mm in diameter, with about 100 florets. Involucre is up to 5 mm tall. Phyllaries in two series, scarious-margined. Ray florets are absent. Disk florets are green, 4-lobed, 1.1 mm long. Achenes are up to 1.1 mm long, ribbed. Pappus is a minute crown or absent. Receptacle is conic. Pineapple Weed is native to Western North America and Eurasia, introduced in many parts of the U.S., naturalized in some parts of India.
Identification credit: Gurcharan Singh
The flower labeled Pineapple Weed is ...