[Members of the Sunflower Family with Button-like Flower Heads in the Columbia River Gorge of Oregon and Washington]

Disc Mayweed, Pineapple Weed

Matricaria discoidea

Synonyms: Chamomilla discoidea, Chamomilla suaveolens, Matricaria matricarioides, Santolina suaveolens

Pineapple weed as seen along the Old Headquarters Road in the Klickitat State Wildlife Area of south-central Washington........May 31, 2009.

Characteristics:

Pineapple-weed is a weedy annual species with branching, leafy stems from 5-40 cm tall. The leaves are 1-3 times compound pinnate and often 1-5 cm long. The leaflet segments are linear or filiform. The heads number several to many. They are rayless, with the disk being greenish yellow and thimble-shaped. The herbage is pineapple-scented when crushed.

Habitat:

Pineapple-weed is found in disturbed or waste places, often along roads, in fallow fields, and in yards.

Range:

Pineapple-weed is widely found over much of North America and Europe.

In the Columbia River Gorge, it is primarily found at the west end of the gorge, and again in mid-gorge, usually in very disturbed areas.

Paul Slichter